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From: njohnson@nosc.mil (Norman F. Johnson)
Newsgroups: rec.guns
Subject: resize pistol brass
Date: 2 May 1996 18:28:47 -0400

Sir,  

# # Can anybody tell me if I need to resize new unfired brass?  I have both
# # straight wall pistol and bottlenecked rifle brass.  Normally I don't
# # resize new brass  and am wondering if I should.

No need to resize pistol brass if bullet grip is good. 

Fitting your lot of cases to a given rifle will pay off in case 
life increase.  To do that I use a little known, but not origi- 
nal, technique:

Using a light charge of powder, seat a heavy (long) bullet into 
the case just enough so that it will not fall out during normal 
handling.  Single load.  The intention here is to cause the 
bullet to be jammed into the origin of the rifling by the bolt, 
thereby holding the case base firmly against the bolt face.  
When the round is fired the case will not be pushed forward by 
the firing pin but rather the case shoulder will be blown forward 
thereby forming the case to the chamber, resulting in zero head-
space clearence.  

The above should be done using the MINIMUM recommended charge for 
any given powder.  Then, using a match or candle, smoke the case 
neck and shoulder 
of one fired case.  Back off your sizing die several turns and 
size the fired case.  Turn the die down in steps until you have 
sized the case (as indicated by the removed carbon) about 95% of 
the neck length.  Be sure that you stop short of the point where 
the die touches the case shoulder.  Once the proper amount of 
sizing is determined, lock the die at that position in the press.

The above has an additional advantage in that with 95% 
resizing, the case base (pressure ring) is reduced back to normal 
diameter, a feature that the neck-only sizer does not offer.  
This is particularly important to those that do relative pressure 
testing according to the Ken Waters' method.  

This technique has been used many years and it 
works.  DO NOT use maximum charges with this method as pressures 
can become excessive.  I use reject cast bullets to do the form- 
ing.  

I have been an active shooter for a lot of years and have not 
ever had a case head separation.  Maintaining a zero headspace 
clearance condition is the reason.  My old Lee-Enfield No. 1, 
Mark 3* has about .020" extra headspace when measured by conven-
tional methods but has effective headspace clearance of zero 
because of the above practice.  I have been shooting it since 
1957 without the first problem.  All my rifles are set up this 
way.  

For semi-auto and lever action rifles, partial resizing after 
firing works only some of the time.  The problem is, depending 
upon that particular rifle's design characteristics and idio- 
cyncracies, cases may "swell" enough after a number of firings 
that they will no longer chamber reliably.  If this is the in- 
stance with your rifle, lube a case that hesitates to chamber 
reliably and tweak your sizer die down about 1/16th of a turn at 
a time then run the case into the die.  Attempt to chamber bet-
ween each 1/16th turn and resizing.  When the case chambers with 
just the slightest resistance (or ideally, with zero headspace 
clearance) lock the sizing die.  It is doubtful that you will 
ever have to change that die setting again (using the same press, 
of course).

I have even used the above for my T/C Contenders, which have no 
camming action to close them, with 100% success.

NOTE: In the case of the M1 (or other semi-autos), do not allow 
the action to slam shut when using the above case adjusting 
method or the slamming of the action may accomplish that which 
the die should do.

Standard full length resizing is ok but this method will increase 
ase life quite a bit and, more important, practically eliminate 
ase failure due to head separation.  

God Bless!

Norm

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: Case Stretching
Organization: Hewlett-Packard Fort Collins Site

K. Karcich (kkrh@troi.cc.rochester.edu) wrote about setting his
sizing die:

: I deliberately set
: the full length sizing die short of the shoulder.

I would bet that when this is done, the resized cases will have headspace
longer than what the chamber has.  My reasoning is based on actual case
measurements when a FL die is so set.  When the bolt is closed on one of
these cases, the locking lugs bear quite hard on their receiver surfaces.
And any lubricant is often completely displaced.  What happens is the lugs
and their mating surfaces in the receiver start to wear; chamber headspace
opens up.

Having seen more than a few rifles that have experienced this problem,
some having headspace open up beyond the `no-go' point and occasionally
past the `field-gage' point, I strongly caution folks not to back their
FL die too much.  RCBS' Precision Mic is an excellent tool to adjust FL
dies to size a case about .001-in. less than chamber headspace.  Otherwise,
strip the bolt and close it on a resized case very gently; if any resistance
is felt, your case's headspace is too long for the chamber.

When FL dies are backed out too far, the shoulder moves forward.  This
happens because the case body is reduced in diameter and the brass has to
go someplace; it lengthens the case body making the shoulder move forward.

I've never seen a rifle shoot as accurate with `extra-long' headspaced
cases as those where the case headspace is about .001 or so shorter than
chamber headspace.  Those longer cases preload the bolt, and, if the bolt
face isn't trued up with the chamber axis, the out-of-square case head
will probably not be oriented the same as its previous firing.  This causes
the barreled action to whip differently than it did before with the same
case.  With a non-trued bolt face but non-square headed cases whose headspace
is a tad shorter than the chamber's, the same thing happens, but to a
lesser degree.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: Some neck sizing questions...
Organization: Hewlett-Packard Fort Collins Site

wayne sugai (wsugai@seanews.akita.com) wrote:
: cartridge brass actually flows under pressure, causing some increase in
: the overall length of the case, as well as thinning the cartridge wall
: (especially near the neck area). repeated shooting exposes the cartridge
: to this hammering effect, which also causes the brass to become more
: brittle. these two are the main reasons why you cannot reload cartridges
: endlessly.

A few years ago, I took one new Federal .308 Win. case and trimmed it to
2.000-in. in length.  Loaded 42 gr. of IMR4064, 210M primer and a Sierra
168-gr. bullet seated to just touch the lands.  After firing the round in
a match-grade chamber, the case shortened by about .002-in.  The case was
deprimed and neck sized in a Jones die with a .336 bushing.  After sizing
the case lengthened to 1.999-in.  The case was reloaded and fired again in
the same chamber, after which the case measured 1.998.  After five more
neck sizing and reloading operations, the case shortened about .001-in
after being fired and lengthened about .002-in. from neck sizing.  At seven
firings, the case was at 2.007-in. and remained at that length for the next
40 loading and firings; shortened about .001 after firing, then lengthened
about .001 after sizing.  I ran out of bullets after 47 shots, but I thought
this test was interesting.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: [RELOAD] Resizing for semi-Auto rifles
Organization: Hewlett-Packard Fort Collins Site

If the same chambering reamer is used to fit two barrels to two receivers,
one a semiauto and the other a bolt action, fired cases from each will be
different in outside dimensions.  The case from the semiauto will be larger
than the one from the bolt gun.  Typically, the one from the semiauto won't
easily slip back into the semiauto's chamber; the one from the bolt gun
will easily go back into its chamber.  I've made measurements on three or
four pairs of rifles (one semi, the other bolt; both chambered with the
same reamer) and in each pair, the fired case outside dimensions were not
the same.

This is the reason that full-length resizing is needed for semiauto rifles.
Most of the time, a standard full-length die works fine.  Once in a while,
a small-base die is needed.  After the case is sized back closer to its
new, outside dimensions, it chambers easily before firing and extracts
easily as the semiauto bolt cycles.

If a fired case does go back into a semiauto's chamber (typically with at
least some resistance) and is neck-sized, reloaded, then fired, the case
won't contract enough after being fired to allow the case to easily be
extracted from the chamber.  More often than not, the case body will be too
tight against the chamber walls and the force of the bolt going back will
cause the extractor to pull the head off the case.  I've seen this happen
many times with M1 and M1A/14 rifles as well as commercial semiautos.  In
each situation the cases were only neck-sized.

I don't think there's any significant difference in accuracy in semiautos
or bolt guns using 7mm or larger bullets in comparing neck-sized or full-
length sized cases.  For calibers smaller than 7mm, sizing and case prep
tends to be more critical for best accuracy.  But unless you are down in
the sub half-MOA range, it probably doesn't matter anyway.

BB


From: toby@u.washington.edu (Toby Bradshaw)
Subject: Re: Comments on Neil Jones' neck die?
Organization: University of Washington, Seattle

In article <Lang-280294141809@128.149.109.63>,
M Lang <Lang@inst-sun1.jpl.nasa.gov> wrote:

#What are "miracle dies"?

They're really just FL dies (some with removable neck bushings, others
with fixed neck diameters) made to size brass the minimum amount necessary
for easy chambering and fast shooting.  They touch the neck, push back the
shoulder to a finished size 0.0005-0.001 below the headspace dimension, and
barely squeeze the base of the case (many PPC cases have a semi-balloon
head that is prone to swell at high pressures, especially since the
last few thousandths is unsupported by the chamber because there has to
be some clearance [~0.003-0.005] between the bolt nose and the barrel).
Lots of good shooters swear by them, but at my level of ability the
$150 is better spent on other things while I ease along with my Redding
FL die (rarely) and my Wilson dies (always).

BR shooting is full of widgets.  Lots of them are overpriced for the
benefits I perceive, but plenty of better shooters than I use some or
all of them.  FL sizing has become more and more popular in BR because
it allows one to get all 5 shots downrange in a single condition (at
least, that's the hope).  With the minimal sizing done by "miracle dies"
case life is usually determined by primer pocket looseness, not web
thinning.  With the hot loads typical of benchrest it doesn't take long
for cases to become tight in the chamber.  It doesn't hurt accuracy,
just speed of firing.

-Toby Bradshaw
toby@u.washington.edu

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: Load pressure question...
Organization: Hewlett-Packard Fort Collins Site

Toby Bradshaw (toby@stein.u.washington.edu) wrote:

: It's pretty hard to get the
: bullet aligned with the bore using a banana as a bore guide.

I like this comment.  And this is why most folks will get smaller
groups with full-length sized cases.

After doing a lot of shooting with neck-sized cases over the past two
years, all of my match rifles shoot groups about 30 to 40 percent smaller
with full-length sized cases.  I'm now a firm believer that if your
cases are `bananas' in shape, they only shoot teenie-weenie groups IF
THEY ARE INDEXED IN THE CHAMBER IN EXACTLY THE SAME POSITION THEY WERE
FIRST FIRED IN.  Full-length sizing straightens out the case more or less
like a `bunned hot dog.'  That straight case will expand uniformly to
the chamber wall diameters and the bullet ends up entering the rifling
straighter.  Therefore, it shoots straighter; groups (scores) are better.

Now, I gotta find out what to do with my Niel Jones neck-sizing die and
all ten of its neck-sizing bushings ranging from .328 to .337 inches.  It
does come in handy if the neck diameter on a full-length sized case is a
tad big; they can be sized down a bit without having to lube and resize
in a full-length die with a smaller neck diameter.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: Load pressure question...
Organization: Hewlett-Packard Fort Collins Site

Toby Bradshaw (toby@stein.u.washington.edu) wrote:

: The problem I see with this is, if your brass is banana-shaped, the
: case head is out of square.

It may or may not be; according to case measurements I've made.  If one
uses the `proper' amount of `proper' case lube, the case head won't be
bent out-of-square as it's pulled out of the die.  With too little case
lube, the force needed to pull the case from the die will bend the head
as the shell holder bears only on about half the rim.

It's possible for some cases to be banana-shaped and still have a square
case head to bear against the bolt face.  But it the bolt face isn't
perfectly at right angles to the chamber axis, the case head will have
its out-of-square angle on a different axis each time the case is resized
and chambered.  Only if the case is indexed the same way in both the
chamber and FL sizing die exactly the same will the case head smack the
bolt face evenly all the way around each time it's fired.

: Even if the bullet is seated out to
: center it in the bore, the case head will be cocked on the boltface.

Again, the previous comments apply.  But this is why a 3- of 4-lug action
tends to produce better accuracy with out-of-square case heads.

: Do you have to push the shoulder back enough to keep the boltface
: from trying to "straighten" the cocked head, thus tipping the
: bullet in the bore?

I keep the case's shoulder about .001 to .002-in. back from the chamber's
shoulder. In other words, the sized case headspace is one or two thousandths
shorter than chamber headspace.  But I don't think the bullet's gonna be
tipped in the throat should the bolt face bear against one side of the
case head when the round is chambered.  For example, if a .308 Win. chamber
has a .456-in. shoulder diameter, a .471-in. diameter about .150-in. in
front of the bolt face and the chambered case is .0015-in. smaller at each'
respective place, the amount of tipping the bullet can make is very small.
If the bullet is concentric with the case axis and seated out to contact
the lands when the bolt is closed, it ain't gonna tip enough to cause
accuracy errors traceable to that cause anyway.

: If the case is reduced in diameter enough
: to keep the bow in the banana from hitting the chamber wall, and
: the boltface isn't trying to push the bullet out of line, I
: can see where FL sizing would be the only way to fix things.  It
: would seem that the real solution would be good brass, or a real
: short case that can't "banana" too much, or both (sounds a lot
: like a SAKO PPC case to me :).

Ah ha! You've identified the big difference between the short PPC-based
benchrest cases and those longer, and larger cases typically used in
highpower matches.  The same scenerio applies to bullet jackets.  The
longer the case (or bullet jacket), the more difficult it is to get it
uniformly straight and fill the machined space (chamber for case, bore for
bullet jackets) they're used in the same for each one used.  Chambers for
the PPC case (or any other small diameter, short length case) are easier to
make near perfectly round than those for bigger cases.


From: toby@u.washington.edu (Toby Bradshaw)
Subject: Re: WRT neck resizing
Organization: University of Washington, Seattle

In article <9405030707.AA24241@ryn.mro.dec.com>,
Dennis Hagarty <hagartyd@snoc02.enet.dec.com> wrote:

#   But what Bart calls a FL resize is a gentle squeeze, and most books,
#   pamphlets, instructions etc show FL resizing to be more like a
#   STRANGULATION or mutilation of the case.

Not really.  If you run cases in the FL die till the shellholder is
touching, most FL dies will produced excessive headspace (from an accuracy
standpoint) in most chambers.  Most reloading books point this out.  The
fact is, most factory chambers are sloppy, most factory brass is way under
SAAMI maximum, and the die makers (the best of whom do an excellent job in
producing SAAMI maximum brass if properly set up) are caught in the
middle.  Measure the base of some unfired brass, and then the neck.  Take
a look and see how far under the SAAMI maximum these numbers are.  That's
why it takes a custom chamber reamer, a custom die, or PPC brass to get a
good fit (most of the time).  Neck sizing alone is a rather sorry solution
to a problem whose basis is indifference of the manufacturers of factory
rifles and brass.

#    But now it seems that the mitigating factor is HEADSPACE. So, Barts
#   pronouncements on the subject might more correctly be summarized:

Actually, the important parameter isn't JUST headspace, it's fit of the
brass to the chamber and boltface and its consequences for bullet
alignment with the bore.  Any method that gives good bullet alignment and
reproducible loading on the bolt/receiver will work.  In benchrest, I've
never been able to tell the difference in accuracy between FL and
neck-sized (or unsized, for that matter) ammo.  As Bart has correctly
noted before, that's most likely because PPC brass is exceptionally
uniform in wall thickness (hence, no "banana" effect or out-of-square case
heads) and because BR smiths do good work with quality reamers well
matched to the available brass.  FL sized brass is faster to shoot, which
explains the popularity of very expensive Hammond (and other) "bump" dies.
If shoulder bumping is as worthless as some "neck-sizers" claim, those
$150 dies wouldn't be so prevalent at BR matches.  And, no, I don't
have one.  If I have to FL size, I use a Redding die.  Mostly I just
live with a relatively hard bolt closure.

#       o If you have the gear to measure headspace to .001" and can set your
#       dies and formulate your lubes correctly, then FL may make a
#       difference (we are talking FRACTIONS of MOA here, not SKS into
#       benchrest rifles).

First, if you have a bolt action rifle you have all the tools you need.
Strip the bolt and size by feel; it's pretty simple.  Second, nothing will
make an SKS into a BR rifle, and I suspect that almost none of the SKS
reloaders neck size, anyhow.  Third, those of us concerned with rifle
accuracy DO care about fractions of an MOA.  From the Cactus Classic
LV grand aggregate shot a few weeks ago:

1	Ed Watson		0.2443
2	Lowell Frei		0.2545
3	Lester Bruno		0.2599
4	Dennis Thornbury	0.2667
5	Faye Boyer		0.2671

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: RELOADING:Neck Sizing, Misc
Organization: Hewlett-Packard Fort Collins Site

Kevin Whyte (KEVIN@MSUS1.MSUS.EDU) wrote:

: 1. Lee claims to have a neck-sizing die that doesn't require any lubrication.
:    Is that true of all Neck-sizing dies?  Is it detrimental to the brass or
:    to accuracy?  Any recomendations or horror stories for specific
:    makers of these Dies?

If your neck sizing die reduces the neck diameter so the mouth diameter is
only 1 or 2 thousandths of an inch smaller than bullet diameter, you may
not need any lubricant.  This is not typically detrimental to accuracy.
The Lee die you are referring to is probably the collet die.  Several folks
have tried them only to find out they don't size the neck enough to hold
the bullet.  This can be resolved by using a smaller diameter mandrel the
neck is sized on.  The only other problem that can arise from using Lee
collet type neck sizing dies is the case shoulder will eventually move
forward enough to be too tight a fit in the chamber; a potential cause of
accuracy problems.  The more conventional neck sizing dies tend to make
more uniform cases when a bit of lube is used on the neck.



: 2. Will the Dies I buy now for the Rockchucker work in a Dillon 550B?  Can I
:    just neck-size with the Dillon or does it require full length?  How
:    accurate and consistant is the powder measure in the Dillon?

You can neck size with the Dillon and use the same dies.  The Dillon powder
measure is about average regarding uniformity of charges it throws.  But a
lot of the uniformity is based on how the press is used.

: 3. Are there any "must have" items that you can suggest?  Something that
:    made your loads more accurate or the process more streamlined.  Are
:    there any software products for the IBM-PC that fall into the above
:    category?

Accurate ammunition and streamlined processes typically don't go together.
There is no free lunch.  Making accurate handloads is usually more tedious
than high-speed production of regular stuff.

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: A reloading Q about F/L resizing in semi's
Organization: Hewlett-Packard Fort Collins Site

Henry E. Schaffer (hes@unity.ncsu.edu) wrote:
: #I notice what seems a lot of case stretching in .223 brass.  This was
: #once-fired, trimmed brass out of a (nearlynew) Colt sporter match HBAR.  Cases
: #trimmed to 1.750 in., then fired and resized, now measure as much as 1.762! A
:                                       ^^^^^^^^^^^^^^^^^^^^

:   When I hear this, the first thing I think about is whether it was the
: resizing - the pulling back of the expander ball through the neck - that
: might have stretched the case.

Every case that's full-length resized, even without an expander ball, is
longer than before it was resized.  How much longer depends on what the
diameters of the fired case were, and the diameters of the sizing die.
When the fired case is made smaller in diameter, the brass has to go
somewhere; the only place it can go is lengthwise.

In my own tests in case length changing due to full-length resizing, both
with and without the expander ball, the difference the expander ball makes
is typically less than a thousandth of an inch.  Even only neck-sizing a
fired case makes it longer; the brass in the neck has to go someplace, too.
But neck-sizing is subject to the same criteria; fired vs. sized diameters.

The more you reduce the diameter of something and keep its mass the same,
the longer it's gonna get.  Brass doesn't compress enough to be measureable
except with perhaps the most sophisticated electronic micrometer there is.
And the opposite is true; the more you expand the diameter of something and
keep its mass the same, the more it's length shortens.  That cartridge brass
has to go somewhere............

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: [RELOADING] Dies that don't wreck your brass?
Organization: Hewlett-Packard Fort Collins Site

All the top highpower competitors have found regular, full-length
sizing dies produce the most accurate ammo.  Oft times, the neck
section is enlarged by lapping to about two thousandths of an inch
smaller than loaded round neck diameter.  This eliminates the need
for an expander ball.  Case necks are very straight and the brass
is hardly worked at all which eliminates metal fatigue.  The most
critical thing seems to be that headspace on the resized case must
be no shorter than about .002-in. than that of a fired case.  An
RCBS Precision Mic lets one determine this.  When the die is too
far down in the press, the shoulder sets back too far causing less
accurate ammo and shortening case life.

Neck-only sizing has not proved very accurate in highpower match
rifles.  New, unfired cases produce better accuracy than neck-sized
cases.  Although theories are very hotly debated, the results speak
well enough for themselves.  The only time neck-only sizing works
is when the chamber is perfectly round and cases have exactly the
same body wall and neck thickness.  I'm not aware of any of these
things existing.

Some competitors use a slightly smaller neck diameter in their
dies, but use an expander ball that's about .3075- to .3080-in. in
diameter.  This barely expands the neck but tends to uniform its
diameter when case necks aren't turned to uniform thickness.  The
end result is excellent.  But the inside of the case necks must be
very clean and free of powder residue to make this process work.

Virtually all commercial .308 Win. sizing dies have neck diameter about
.326- to .330-in.; too small for the best ammo.  Any 'smith worth
his buisness card can lap a die to about any neck diameter needed.
Interestingly enough, these standard dies do a great job with Rem. BR
cases with their thin necks without expander balls.  I use one for
my 300-yard ammo using Rem. BR cases and the results are impeccable.

During the last two years, I tested about 2,000 rounds of neck-sized
only cases using a Niel Jones die with bushings ranging from .327- to
.337-in. depending on case neck wall thickness.  I sized case necks to
different dimensions smaller than loaded-round neck diameters.  None of
this stuff shot groups at 1000 yards (or any shorter range) as small
as full-length sized cases.  The smallest 20-shot groups attained with
neck-sized cases was about 1.5 MOA; with full-length sized cases, groups
got down to about 0.6 MOA at 1000 yards and somewhat smaller at the
shorter ranges.

I used both .308 Win. and .30-.338 rifles in these tests.  Across five
different rifles, full-length sized cases shot smaller groups than those
using neck-sized cases.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: 550 rifle loads
Organization: Hewlett-Packard Fort Collins Site

Ole-Hjalmar Kristensen (ole@delab.sintef.no) wrote:

: But brass from different manufacturers (and
: lots) have different thickness, and if I don't use the expander ball
: without having reamed the neck to uniform thickness, won't the force
: needed to seat (and dislodge) the bullet vary a lot?

Yes, it will.

So you get to decide whether or not you want to use the same make/lot
of brass without an expander ball and get excellent accuracy, or do
something else.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbit)
Subject: Re: [RELOAD] lubing inside of necks (was Re: Questions about reloading 
	and .308)
Organization: Hewlett-Packard Fort Collins Site

Richard A. Wooden (rwooden@mantis.digex.net) wrote asking about:


: #Years ago, I tried this method.  But it was too much work.  I finally
: #lapped out my full-length sizing die necks to what I wanted.  No more
: #expander balls.  A much simpler process.  More uniform sized-case
: #headspace.  All of which resulted in more accurate ammo.

this question:

: Would it be to much to ask how you went about doing this?

Heck no.  Here's how I did it.

I put the die in a lathe held by a collet.  Then put fine emery paper
on a split wood dowel.  By spinning the die and putting the dowel with
emery paper on it, I lapped out the die's neck.  Measuring with a hole
micrometer every so often until it was the diameter I wanted.

I lapped the die until its neck diameter was between 1 and 2
thousandths of an inch smaller than the neck of a loaded round.

This really results in very straight cases.  Plus, case life is
greatly extended because the neck only moves once during sizing.
With an expander ball, the neck moves twice; once being squeezed
down and again being expanded back up.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: Rifle Case Life Questions.
Organization: Hewlett-Packard Fort Collins Site

sfaber@intgp1.att.com wrote:

: I have a problem where the head to shoulder distance will
: vary by several mils case by case after resizing.  I was wondering
: if you have a distribution too, or do they all size out to 1 mil or less
: precision?

Mine have a sized case headspace spread of less than 1 mil.  I attribute
that to my sizing lubricant: 1 part Hoppe's No. 9 and one part STP engine
oil treatment.  That case lube mix is thinner than most others and I only
need a very little bit on each case.  Cases go into and out of my FL dies
very easily.

One can easily get a 3 to 4 mill spread in FL sized cases if the lube is
non-uniformly put on the cases.  Too much lube results in sized case
headspace being too short; too little equals too long.  And if the lube
is more on one side than the other, the case will be bananna shaped.
Thicker lubes tend to cause more problems than thinner lubes.  I tumble my
cleaned cases in a Thumbler's Tumbler lined with quarter-inch soft
foam that's had a few drops of my case lube put on it.  That gets a very
even coating of case lube on each of the 100 cases I lube at a time.
After dumping them out, I re-drop the same amount of case lube on the
foam, then put in another 100 cases.  Doing several hundred cases this
way, sized case headspace is within a 1 mil spread across all the cases.

Lapping the necks of dies does eliminate the need for an expander ball.
But if the case mouth is first clean, then lightly lubed, the expander
ball shouldn't cause any sized case headspace differences.  If it does,
I suggest turning the necks to where they are thinner.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: case lube
Organization: Hewlett-Packard Fort Collins Site

Keith de Solla (keith@orion.ic.cmc.ca) wrote:
: In article <C9y74L.MuC@fc.hp.com>, bartb@hpfcla.fc.hp.com (Bart Bobbitt) writes:
: |> I think you want to get some lube on the outside of the neck of necked
: |> brass.  Otherwise, there won't be any lube between the case neck and
: |> the neck part of the sizing die.  What's your reason for not wanting any
: |> lube on case necks?

: I read somewhere that it wasn't a good idea, though at the moment I cannot
: recall the reason.  Old wive's tale, perhaps?

Some reloading instructions in print mention not putting any lube on the
shoulder or neck.  I've never quite figured this out.  There may be some
lube that works its way from the die's body wall section up into the
shoulder and neck section, but that probably won't happen until several
cases have been sized.  Reader's comments are welcomed regarding this.
There may be some concern that folks will get too much lube on the shoulder
and neck area as to cause the shoulder to dimple from excess lube.

I think that as long as the case lube is removed from the case, both outside
and inside, that's the important thing.

But then, most reloading manuals instruct users to screw a full-length
sizing die in to where the shellholder just touches it with the ram at the
top of its stroke.  As this more often than not sizes case headspace too
short for both accuracy and case life, it does guarantee the sized case
will chamber in just about any rifle there is for that cartridge.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: case lube
Organization: Hewlett-Packard Fort Collins Site

Mika Matti Jalava (mjalava@alpha.hut.fi) wrote:

: Really, does graphite work as an abrasive?

Sure does.  Ask any respectable machine shop or tool and die maker.
It's a pretty fine abrasive, but lightly rubbing some on a polished
steel surface leaves microgrooves visible under a strong magnifying
glass or microscope.  But it does tend to lubricate to some degree
and smooth up metal parts rubbing against each other.  It should be
used only on things where fit tolerances are greater than .001-in.

An example in the shooting sports product warranties about graphite
is Alan Warner's rear sight's warranties are voided if graphite is
used on 'em.  Some folks have used graphite on adjustable sights to
make 'em smooth and nice-feeling.  Mr. Warner says to use only a
light machine oil to lube his sights; graphite micro-laps the lead
screws and their bushings, guide pins and adjustment knobs.  He
won't guarantee repeatability if graphite is used.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: [RELOADING] Rifle case resizing lube recommendations?
Organization: Hewlett-Packard Fort Collins Site

Bryan Call (bc@col.hp.com) wrote about my:
50% Hoppe's No. 9 bore cleaner and 50% STP engine oil treatment.

: Sounds interesting.

Thought so myself about 20 years ago when I learned about it.

: Just how did you come upon this particular combo?

Asked one of the country's top highpower competitors what he used.  He
told me.

: What good characteristics does it provide?

Ease of sizing cases.

Cleans off easy with Joy (liquid diswashing soap) mixed with hot water.

: Any downsides?

I don't stimulate the local economy by buying case lube at the local
gun shops.  A can of STP and an equal amount of No. 9. is cheaper than
an equal amount of gun lube.

: Do you just put it on your lube pad like normal?

No, I don't use a lube pad.  Those things don't lube cases very uniformly.
That causes cases to vary in headspace and get banana shaped.  I put 100 or
so cases in a foam-lined coffee can that slowly spins on my 2,000+ year old
Thumbler's Tumbler base.  The foam has been dabbed in a few places with my
9+STP and after tumbling for about 10 minutes, the cases have a very uniform
and very thin coating of lube.  Full-length sizing those cases is very easy
and they come out uniform in headspace to no more than a .001-in. spread.
Plus, they are very straight, too.

: Any particular tips on
: application amounts or techniques?

Don't use very much.  That stuff is very much like Brylcream hair stuff;
`A little dab'll do ya!'

BB

From: Doug White <gwhite@ll.mit.edu>
Subject: Re: WRT neck resizing
Organization: MIT Lincoln Laboratory

In article <9404280148.AA20400@wsuaix.csc.wsu.edu>,
# I have to agree with Bart on the problems of "partial body sizing"
#
# The chamber on my new rifle was only .001" over SAAMI minimum as measured
# by the RCBS precision mic (great piece of equipment).
#
# When I ran a fired case through my resizing die that had been set up
# "to touch" the shellholder I found that the shoulder had been _set forward_
# about .003-.004
#
# I was eventually able to reconcile this with the fact that the brass had to
# go somewhere and tried the case in the rifle--sure enough, it was hard
# to chamber (relatively speaking)
#
# I ended up having to screw in the die about another full turn (probably my
# crappy Lee press flexing) and cramming the case as far as I could into the
# die to get the required .001" setback of the shoulder
#
# This is also pretty good proof that the necks grow in the resizing die and not
# in the chamber as the set forward brass also has to go somewhere and the
# neck is the logical place for it.
#
# a newbie accuracy reloader and trying hard
#
# marc

I had similar problems with the Lee RGB dies which I used to make up the
abrasive loads used for 'fire lapping' my .308.  Rather than springing my
press, I cut some shim stock with a rounded tab the size of the cartridge
base, and a hole to clear the primer.  There's enough slop in the shell
holder to easily slide a case in on top of the shim.

Speaking of presses springing, I discovered something interesting while
checking my seating depth.  I use a case with a slot cut in the neck to
check the seating depth in the rifle.  In order not to force the bullets
into the lands, the neck tension needs to be fairly light for this
measurement.  If I use the same test case to check the seating die, I
get loads that are more than 5 thousandths too long.  The force required
to seat the bullet into a sized case neck springs my RCBS Rockchucker
(which isn't exactly a wimpy press) by that much.  I'm loading copper
jacketed bullets into Lake City Match cases (which are thicker and stiffer
than commercial case), but I was still surprised that the process
required enough force that it would spring the press that much.

Doug White
MIT Lincoln Laboratory


From: Doug White <gwhite@ll.mit.edu>
Subject: Re: Reloading-Neck Sizing only
Organization: MIT Lincoln Laboratory

In article <Coww4v.FBJ@newcastle.ac.uk>, <J.M.Spencer@newcastle.ac.uk> writes:

# bartb@hpfcla.fc.hp.com (Bart Bobbitt) writes:
#
# #ROSS, GEORGE RAY, JR (grr7634@zeus.tamu.edu) wrote:
#
# #: Why would full-length sizing produce more accurate ammo?  I just recently
#
<lengthy discussion of Bart's OPINION that full length sizing being the ONLY
 way to reload for accuracy vs Jonathan's concern that such uncompromising
 positions stifle healthy experimenting>

Just to stir the brou-ha-ha a bit further, I was reading Sinclair's Reloading
Book (mostly aimed at benchrest, but lots of good stuff in general), and
he claims that most bench rest shooters get better accuracy by neck sizing.
He also says that SOME rifles will shoot better with full length sizing, but
that they are the exception rather than the rule.

It is possible they are both right, but that would imply that there are
subtle differences between the bench rest guns Sinclair is used to, and the
Palma rifles Bart is experienced with, although I believe Bart also does
benchrest.

I believe Sinclair mentions that this is one of several areas where opinions
of many excellent shooters differ.  Precision Shooting Magazine has had
some wonderful discussions started by asking a dozen top shooters an inocuous
question like: How do you clean your rifles?  There are always at least 2
and frequently 3 approaches to every problem.  I have come to the conclusion
that there are always several WRONG ways to do almost anything associated
with accurate shooting.  However, there may frequently be more than one
'RIGHT' way to do something, which may vary from shooter to shooter, and
rifle to rifle.  As a relative beginner to highpower rifle shooting, I start
by trying to make sure that I'm not doing anything wrong.  Then I try to
get as many opinions on how to do things 'right' as I can.  From there, I
get to enjoy sorting out what works for me.  Also, what is 'right' today
may be wrong tomorrow.  Just in the last year, I've read several articles
that claim that using ammonia based bore cleaners in stainless barrels leads
to micro-crazing of the bore.  This may not be as big a problem as some
claim, but there are plenty of other solvents on the market.  I'm not using
an ammonia cleaner until all the facts are in.

Hey, if it was all cut-and-dried, it would be boring.

Doug White
MIT Lincoln Laboratory



From: Doug White <gwhite@ll.mit.edu>
Subject: Re: WRT neck resizing
Organization: MIT Lincoln Laboratory

In article <CozDy5.JpJ@fc.hp.com>, <bartb@hpfcla.fc.hp.com> writes:

# Doug White (gwhite@ll.mit.edu) wrote:
#
# : If I use the same test case to check the seating die, I
# : get loads that are more than 5 thousandths too long.
#
# I get cartridge OAL variances that much myself even when bullet
# seating pressure is down around 5 to 10 pounds, not the 50 to 70
# pounds typical sizing dies enable.  The reason is probably not
# so much press springing, but the bullet dimensions involved.
#
# Most bullets vary close to 5 thousandths of an inch from their tip
# back to a datum point equal to bore diameter just in front of their
# bearing surface.  It is this datum point that determines how far
# bullets jump from their seated position to the lands; not their tip.
#
# If one does the measurements correctly with the right tools, one will
# find out that some cartridges at the max limit of OAL have this bullet
# datum point further back towards the case head than some cartridges at
# the minimum OAL limit do.
(snip)
# BB

I was using the RCBS case mic, and a Sinclair bullet comparator, both of
which measure to the ogive, not OAL.  Using the case mic, I get a loaded
length variation of +/- .001" out of my press with full length sized cases.
The shorter length I measured with a sliding fit test case is quite
repeatable, which means SOMETHING is flexing under the force required to
seat the bullets in the sized cases.

Doug White
MIT Lincoln Laboratory


From: Doug White <gwhite@ll.mit.edu>
Subject: Re: WRT neck resizing
Organization: MIT Lincoln Laboratory

In article <CozGBz.LFz@fc.hp.com>, <bartb@hpfcla.fc.hp.com> writes:

# Doug White (gwhite@ll.mit.edu) wrote:
#
# : Rather than springing my
# : press, I cut some shim stock with a rounded tab the size of the cartridge
# : base, and a hole to clear the primer.  There's enough slop in the shell
# : holder to easily slide a case in on top of the shim.
#
#
# I don't understand the mechanics of how doing this wouldn't still
# spring the press.  Seems to me all that's happening is the case
# gets pushed a few thousandths of an inch further up into the die
# with the shell holder stopping at the same place as before.
#
# Perhaps I'm not understanding something; please explain this again.
#
# BB

The problem I was responding to was that the lengths of the sized cases
were too long for easy chambering, even with the ram touching the shell
holder (this is using CHEAP dies).  The original author was tackling the
problem by compressing the ram against the shell holder, which springs
the press.  The shim is used to lift the case 0.005" up further into the
die with the ram just touching the shell holder, without applying an
additional force to the press.  The press is still going to have some
spring, but no more than usual.  I think you understood my solution,
but perhaps not the original problem I was trying to answer.

Doug White
MIT Lincoln Laboratory


From: Doug White <gwhite@ll.mit.edu>
Subject: Re: Full Length Sizing
Organization: MIT Lincoln Laboratory

In order to maximize the life of my brass, I would like to have my sizing
die lapped out so that I don't have to mess with an expander ball.  I spent
some time last night measuring case wall thickness to begin to get an idea
of what size to lap to.  Unfortunately, I seem to have a bit of a tolerance
problem.  I have 4 types of cases, and they are all measuring (within each
case type) +/- 1.5 thousandths variation, sometimes within a single case.
For example (all measurements are neck wall thickness):

Winchester new commercial brass:  0.013"-0.016", many cases are +/- 0.001"
or less, but some cover the full range.  These are unfired primed cases,
which may affect the measurement a bit.  The Sinclair Case Gauge I'm using
has a guide pin that's supposed to go up thru the primer hole, which I can't
use with the primed cases.

Lake City Match '90:  0.015"-0.018", same sort of variation in neck
thickness both from case to case, and within a single case

Lake City Match '89:  0.020"-0.023", quite a bit thicker, but similar
variations.

Yugoslavian Commercial:  0.015"-0.018", similar range, but each case is a
bit more uniform.

I view the Winchester cases as 'My good stuff', and the rest as practice
ammo.  If I want to lap the die for the Winchester stuff, there is still
the wall variation to deal with.  Unless I want to neck turn every case,
I'm assuming I'm going to get a fair amount of neck tension variation if
I size all of these cases to a uniform O.D.  Is this going to be a
significant problem?  Should I just have the die lapped for the middle
of the thickness range, or do I now have to invest in a neck turning
set-up as well?

Also, If I have my die lapped for the Winchester cases, I clearly can't
use it without an expander ball for the LC '89, which averages 5 thousandths
thicker.  My next question is whether the die could be used for the
thicker cases WITH the expander ball.  The problem is how much 'spring-back'
the brass has.  Each forming operation must move that brass past its
elastic limit, or the brass will spring back to its original size.  If
the brass is only compressed a few few thousandths tight by the sizing
operation, it may spring back after the expander goes through.  This
would leave me with some VERY tight cases.  How much compression in required
to guarantee that the brass will actually change dimension, and is the
spring back going to cause me grief?  The Yugoslavian and LC '90 are only
a bit bigger (on average) than the Winchester, but some cases overlap.
I can always use a standard die with this stuff, and not worry about the
case life, but I'm curious about what I can get away with, and what the
consequences might be.  In the future I'm going to stick with selected lots
of commercial cases, but it seems silly to scrap it (I've got over 700
rounds total of the 'cheap stuff').

Comments, wisecracks, and ravings welcome.

Thanks!

Doug White
MIT Lincoln Laboratory


 












































































































































































































































































































































































































































































































































































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