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From: bartb@hpfcbart.fc.hp.com (Bart Bobbit)
Subject: Re: .308 loads
Organization: Hewlett-Packard Fort Collins Site

Although many different components are used in the .308 Win. for competition,
those that win most of the matches and set virtually all of the records are
seldom seen in print.  For example, the use of ball powder seems to be a
popular thing, but ball powder has never produced off-the-shoulder accuracy
up to the level of extruded (stick) powder.  Although ball powder meters
more uniformly and can produce equal-size groups at long range as extruded
powder from machine rests, it doesn't seem to perform as accurately as extruded
powder when fired from the shoulder.  Most folks feel ball powder takes longer
to get the bullet out of the barrel than extruded powder and that's why scores
are higher when extruded powder is used.

Here's the loads that the top USA highpower competitors use to get sub
half-MOA groups in their bolt guns and sub MOA groups in their service
rifles:

  * 200- and 300-yard favorites for service rifles:

    > Federal or Winchester case, full-length sized.
    > Federal 210M or Remington 9-1/2 primer.
    > 42 to 44 grains of IMR4895 or IMR4064.
    > Sierra 168-gr. bullet.

  * 200-yard favorite for bolt guns:

    > Federal or Winchester case, full-length sized.
    > Federal 210M or Remington 9-1/2 primer.
    > 40 to 41 grains of IMR4064.
    > Sierra 168-gr. bullet.

    or....

    > Remington BR case, full-length sized.
    > Remington 7-1/2 benchrest primer.
    > 42 grains of IMR 4064.
    > Sierra 168-gr. bullet.

  * 300-yard favorite for bolt guns:

    > Remington BR case, full-length sized.
    > Remington 7-1/2 benchrest primer.
    > 42 to 43 grains of IMR 4064.
    > Sierra 180-gr. bullet.

  * 600 through 1000 yard load for service rifles:

    > Federal or Winchester case, full-length sized.
    > Federal 210M (a uniform lot, if you can find one) or RWS 5341 primer.
    > 43 grains of IMR4064 with the Sierra 180-gr. bullet.
    > 44 grains of IMR4064 with the Sierra 168-gr. bullet.
      Note - Cartiruccio bullets in the same weights are also used with
	     great success.

  * 600 through 1000 yard loads for bolt guns:

    > Uniform case as light weight as possible, such as WCC58 or WCC60, the
    > earlier Winchester cases, full-length sized.
    > RWS 5341 primer.
    > IMR4064 powder, charge weight as follows for different case weights;
        + 42.5 grains in case weighing about 150 grains (WCC58).
	+ 42.0 grains in case weighing about 157 grains (WCC60 or early
	       Winchester cases).
	+ 41.5 grains in case weighing about 165 grains (current Federal,
	       Winchester, or the '92 Winchester Palma cases).
    > Sierra or Cartiruccio 190-gr. bullet.
      Note - Sierra's 200-gr. or Berger's 210-gr. bullet can also be used
	     if the powder charge is reduced about 1 grain.

    or...

    > Remington BR case, full-length sized.
    > Remington 7-1/2 primer.
    > ~43 grains of IMR4064 with a Sierra or Cartiruccio 190-gr. bullet.
    > ~47.5 grains of IMR4350 with the Sierra 200-gr. bullet.
    > ~42.5 grains of IMR4064 with the Sierra 200-gr. bullet.
    > ~42.0 grains of IMR4064 with the Berger 210-gr. bullet.

Although Federal's 210M primer is very popular, it does not have the
shot-to shot uniformity as the RWS-5341 primer for use at the longer ranges.
It's also a bit too hot for the most accurate loads at long range.  RWS's
No. 5341 is a milder primer and is more uniform both within a lot and
between lots than the 210M.  Remington's 9-1/2 primer has been very good
when a uniform lot is used.  The issue seems to be that milder primers give
smaller groups than stronger ones.  Which makes sense as the bullet's base
will be deformed less when the initial pressure curve rises slower due to
milder primers than faster with the stronger ones.  In all my tests for
accuracy, milder primers have always produced smaller groups than stronger
ones at ranges of 300 yards or greater.  At 200 yards or less, the primer
intensity doesn't seem to matter that much.  When the Remington 7-1/2 BR
primer began showing up in highpower matches for use at 300 yards, one of
the first thing that happened was the 300-yd. rapid fire record immediately
jumped to 200-18X and other 300-yd. scores improved.  It was also used in
1987 to up the Palma course record to 450-29X over the earlier 450-22X score.
Primers are about 60% of the accuracy a load produces.  The best way to test
primers is with a chronograph.  Those that produce the lowest and most uniform
velocities typically deliver the smallest groups.

A lot of hoopla has been in print about Berger's 185-gr. Very-Low Drag (VLD)
match bullet.  But they actually have a lower ballistic coefficient than
Sierra's 190-gr. bullet as proved in remaining velocity tests at 1000 yards.
And the Berger 185-gr. bullet seems to be a tad less accurate than a good
lot of Sierra 190s; the equal of regular lots.

I'm beginning to think Sierra's 155-gr. Palma bullet is an excellent choice
for service rifles.  In a 1:12 twist, they can be driven fast enough in a
22-inch M1A or M14 barrel (also the 24-in. M1 barrel) to spin them fast
enough to stablize them yet not so fast to cause those not quite as well
balanced to be less accurate.  The only limitation is they can't be shot
fast enough in service rifles to remain supersonic at 1000 yards.  An
excellent load for this bullet in either service rifles or bolt guns is:

  * Federal or Winchester case weighing about 165 grains, full-length
    sized.

  * Federal 210M or RWS 5341 primer.

  * 44.5 grains of IMR4895.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: .308 Palma Bullet Loads
Organization: Hewlett-Packard Fort Collins Site

During the semifinal tryouts for the '95 USA Palma Team, a lot of discussion
regarding what loads for Sierra's Palma bullet took place.  Here's the gist
of those discussions for folks desiring to develop accurate, long-range loads
for that bullet.

Those eligible to compete in the tryouts were the ones placing in the top 200
in an aggregate including scores from these matches:

  * Three, 20-shot matches at 600 yards; part of the NRA Championships.

  * The 45-shot Palma Match; 15 record shots at each of 800, 900 and 1000 yds.

IMR4895 was the powder of choice for most folks.  Charge weights varied from
44.3 to 45 grains.  Some folks threw charges direct from measures; others
weighed every charge to a +/- .05-gr. spread.  Interestingly enough, the
powder lots had varying degrees of fouling.  That's not surprising as IMR4895
is one of the `dirtier' powders on the market.  Most folks didn't clean their
barrels during the day on the range.  Others drybrushed after each, or every
other 15- or 20-shot stage.  Many of the top scores were shot using IMR4895.

Reloader 15 came in second place.  I don't know the charge weights used.  But
both metered and weighed charges filled their cases.  Bores were fairly clean
from using it.  I'm not aware of any users who cleaned their barrels during
the shooting day.  RE-15 was also behind a lot of the top scores.  In fact,
it was used by the person who was number one on the list at the end of day one.

The Finnish powder, Vihtavouri (sp?) Oy N140, close to IMR4320 in burning
speed, was used by one person who was in second place after the first day.  He
finished the tryouts in, I think, 3rd place overall.  This powder meters very
well, burns pretty clean, and produces excellent velocity control; according
to the person who used it.  Interestingly enough, the distributor was giving
away quarter-pound samples of this powder to anybody with a competitor's
tag.  This new powder in the USA deserves close scrutiny; it's demonstrated
all of the best qualities needed for competitive shooting.  N140 may have been
used by a few others.

H-4895 had a few users.  Scores with it were average.  Nobody making the team
used it.

IMR4064 had a token showing.  I know of only one person who did well using it.
And that was with a rifle borrowed from his friend's wife, along with the ammo.
He made the cut for the team with pretty good scores.  A couple of folks used
about 46+ grains and claimed 3200 fps with it in 30-inch barrels.  Those 155-gr.
bullet cores must have been almost at the melting point; that's pretty fast
for a .308 Win. to drive 'em.  They claimed excellent accuracy with them, but
none of these folks made the cut for the team as far as I know.

Regarding ball powder, I'm not aware of anyone using it during the tryouts.

RWS-5341 primers were used by most of the top-scoring shooters.  Federal's 210M
was the most popular; some of the top scores were primed with 'em.  A minor
sprinkling of other primers were used; none of which produced decent scores.

Winchester's 1992 Palma Match case (from the '92 International Match) as well
as their new .308 Palma case dominated the top scores.  Some folks used cases
from Federal.  A few folks used Lake City Arsenal's military match cases but
didn't fare too well with them.  A few used other brands.  Case weights that
were used were about 165 to 166 grains for the commercial cases.

Bullet seating practices varied.  Some had the bullet soft-seated and it was
pushed back into the case several thousandths of an inch upon closing the bolt.
Others had a few thousandths jump to the rifling.  Most top-scoring folks who
made the team used soft-seated bullets.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: Want a .308 PSS Accuracy Load
Organization: Hewlett-Packard Fort Collins Site

David Putzolu (dputzolu@cs.uiuc.edu) wrote:

: I've got match brass from
: Remington, Winchester, and Federal, and would like the following
: specific info:
: What powder - exact weight to use?

I don't know what powder charge weight is best.  That depends on the bullet
and barrel's groove diameters.  Factory barrels have different groove
diameters from barrel to barrel.  In .308 Win., groove diameters are between
3075-in. and about .3085-in., maybe bigger.  Depending on how tight the
bullet fits the groove, the burning powder's pressure curve will vary.  This
means the exact charge weight needs to be determined by a chronograph and
the charge weight that gives the lowest velocit standard deviation is the
most accurate one.

I would guess the powder/charge of choice would be about 41-43 grains of
IMR4064 for the bullet weights that factory 1:12 twist barrel will stablize
the best.  You'll have to test different charge weights to find out what's
The best.  These bullet weights are between 165 and 180 grains.

: What primer - any particular brand of primer? Match/Benchrest?

I suggest the mildest large rifle primer you can afford.  The mildest is
the RWS5341, second mildest is the Rem. 9-1/2 standard.  Winchester, Federal
and others are too hot for best accuracy.  Forget CCI.

: What bullet - this will be for paper punching at ~100 yards.

As bullets need to be at least .0004-in. larger in diameter than the
barrel's groove diameter for best accuracy, you should slug that factory
barrel and measure its groove diameter to the nearest .0001-in.  If the
groove diameter is larger than .3080-in., the Lapua .3092-in. diameter,
170 grain match bullets will probably shoot the most accurate.  If the
groove diameter is smaller, then Sierra's 168 or 180 grain HPMKs will
probably do well.  But, to often is the situation where flat-based bullets
shoot more acccurately in factory barrels than boattail match bullets.
Try some flat-based hunting bullets that are larger in diameter than the
barrel's groove diameter.  There enough unknowns here to not be able to
just say brand X bullet, style Y will be the most accurate.

: What procedures - should I full length/neck resize? Crimp at all
:   (probably not)? What bullet seating depth? Should I clean/polish
:   the brass?

Full-length size for best accuracy in that factory barrel with factory
chamber.  But throw away the expander ball and get the FL sizing die's
neck lapped out to about .002-in. smaller in diameter than the neck
diameter of a loaded round.  This way, the case neck won't be bent as the
expander ball comes up through it and the case neck will not get work
hardened so quickly; you can get 40 - 60 loads per case this way.

I don't recommend crimping bullets if accuracy is the primary goal.
And bullets without a crimping groove shouldn't be crimped anyway.

Deprime your brass and either tumble or vibrate it to clean it.  Run a
bore brush held in an electric drill inside the case mouth to clean out
all the powder residue.


Seat the bullets to touch the lands as a start.  If all the
lands don't make contact with the bullet evenly, then seat the bullet out
far enough so it soft-seats back into the case as it jams into the rifling.

: I have the Hornady and Sierra reloading books and have asked for
: reloading info from powder manufacturers as well, but I've noticed
: that there is a fairly big diff in barrel length between the Hk-91,
: for instance, and the test barrels used by Sierra and Hornady (26"
: and 22"). Does this 4"+ difference make a different loading (perhaps
: faster powders to be used?) than listed in the manuals preferable?

Barrel length doesn't have much impact on powder type used.  The biggest
cause of powder type differences for accuracy is bullet weight.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: [Rifle} Palma...
Organization: Hewlett-Packard Fort Collins Site

Todd Enders A262 857-3018 (enders@warp6.cs.misu.NoDak.edu) wrote:

: Besides,
: rifles are individuals, so what works best in one gun may not be worth a
: hoot in another.  With handloaded ammo, one can isolate the best load for
: *their* rifle.

Interestingly enough is the fact that the top highpower shooters use
virtually the same handload components.  That's because their barrels have
virtually the same bore and groove diameters.  And the chambers were cut
with reamers ground to near exact dimensions.  Under these circumstances,
it's not unusual to note they all use the same stuff for their handloads.
I would not be surprized if benchresters do the same thing.

This concept that each rifle needs its particular set of handload
components comes from two much greater numbers of shooting things:

  * Most folks don't shoot enough shots to realistically evaluate a given
    handload's performance, nor do they shoot well enough to get meaningful
    data in the first place.  Not to belittle anyone's own attitudes, but
    this is just what happens.

  * Most rifles have factory barrels and chambers whose dimensions go all
    over the place screwed into an action whose intrinsic accuracy level
    is at the lower end of the curve.  Screwing these metal parts into a
    misfit stock and expecting accuracy performance resolution to less than
    a half MOA is unrealistic.

When both the above are combined, all sorts of claims are made regarding
what's the best handload component, reloading process, rifle and sights.

BB

From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: [Rifle] Palma...
Organization: Hewlett-Packard Fort Collins Site

Todd Enders A262 857-3018 (enders@warp6.cs.misu.NoDak.edu) wrote in
response to:

: ##Interestingly enough is the fact that the top highpower shooters use
: ##virtually the same handload components.That's because their barrels have
: ##virtually the same bore and groove diameters. And the chambers were cut
: ##with reamers ground to near exact dimensions. Under these circumstances,
: ##it's not unusual to note they all use the same stuff for their handloads.
: ##I would not be surprized if benchresters do the same thing.

:      Ah, but in a sense, they have isolated an optimum load.  Changing to
: a different primer/powder/bullet/case opens up groups, no?

Changing a component may or may not open up groups.  Remember that a given
rifling twist rate produces best accuracy for a given bullet within a
fairly narrow velocity range.  As their specific barrel is used with only
one to perhaps three different bullet weights, that is probably a good
example of isolation for bullet weights.  And there's typically only one
or two powder types that produce lowest velocity spreads to keep vertical
stringing to a minimum.  Varying the powder charge weight a few tenths of
a grain doesn't have much effect on accuracy.  Primers are probably the
biggest contributor to poor accuracy in a properly built match rifle.  If
they are too hot and not very uniform in their ignition, the powder isn't
burned uniformly from shot to shot.  Primer mildness and uniformity are
more important at the longer ranges.

:      Given the assertion above, it gives one pause to wonder why the top
: highpower shooters bother to reload at all.  Certainly, a custom ammo
: production facility could produce the rounds, and at a cheaper price than
: individual production (buying the components in quantity at a discount).

Almost true.  The biggest differences between match rifle A and B tends to
be in headspace and throat length.  Handloading for your own rifle permits:

  * Full-length sizing cases to have their headspace about .001-in. less
    than the specific rifle's chamber headspace.  And sizing the neck to
    attain proper neck tension for either rapid- or slow-fire ammo.

  * Seating the bullet as long as possible to enable soft-seating for long
    range loads and just short enough to function through the magazine for
    rapid fire ammo.

Mass produced ammo can be, and has been, quite accurate.  But just not as
good as ammo reloaded specificly for the situations identified above.  And
the cost of such ammo is about twice that of what handloading good stuff
yourself will cost.  The biggest problem in mass produced ammo is getting
the best powder's charge weight uniform enough.

: It may well be that rifles have reached a level of mechanical perfection
: where their individuality is becoming lost in the noise (I'm speaking of
: match and benchrest rifles here).  I'm still a bit dubious, though.

To a great degree, this is true.  As custom barrel and reamer maker's
products typically excell with a narrow band of bullets and cases, the real
difference are not too discernable.  That in itself is credit to those
dedicated few who produce extremely uniform products that perform to the
highest levels.

But the quality of match bullets made these days is a significant
contributor to this success.  Competitive shooters use a few makes and a
few weights to be successful.  'Tain't easy to change rifling twist so
a big change in bullet weight can be used at the fastest velocity it can
accurately be shot at.

Regarding Toby's remarks:

: #I've shot sub-
: #half-inch 20-shot groups at 100 yards while varying the powder charge
: #from fireforming (24gr) to match loads (28gr) and shooting 2 or 3
: #different bullet makes/weights.

and these comments:

: Whoa, hold the phone!  I hope you're not trying to tell me that you could
:pull out 20 rounds at random, prepared within the parameters above, and have
: them all go into the same hole at 100 yds.

Why would you hope he's not trying to tell you this?  It happens all the
time with proper equipment.  But by the same token, you're not going to stop
by your local car dealer, buy something from the showroom or sales lot and
go win the Indy 500 with it either.  Nor should someone expect a point and
shoot camera to produce picture quality equal to that of a Nikon, Leica,
or Hasselblad.

In early 1991, several match rifles were used to test different powder types
and charge weights for Sierra's new 155-gr. 30 caliber match bullet.  Several
case makes were used for these tests.  After all testing was done at 1000
yards, the difference between the smallest and largest 15-shot test groups
was about 4 to 5 inches.  All groups varied between about 9 to 14 inches
across eight different barrels from three different makers.  Interestingly
enough was the fact that all those barrels shot the best groups with one
powder make and within a few tenths of a grain of the same charge weight.
Case make didn't have much effect as they were reasonably uniform in weight
and dimensions; and they were all full-length sized.  Had the tests been
conducted at 100 yards, the tiny, one ragged hole groups would have been
about one quarter to three eighths of an inch between widest shots.  Any
discrimination process as to what load gave the best accuracy would have
been hard to do.

A year later when folks handloaded these bullets for their own rifles using
the aforementioned processes, their 1K-yd. groups went down to about 6 to 7
inches.  That's the advantage of handloading your own ammo; just a refinement
to get the best accuracy out of one particular rifle.  That same year, near
400,000 rounds of match ammo was mass produced on Dillon 1050 progressive
reloaders.  All powder, cases and bullets were from the same lot.  Over
20 lots of primers were used.  And as predicted, the loaded lots of ammo
with greatest powder charge variance typically shot the least accurate.  A
few lots of that ammo shot near 40-inch groups at 1000 yards; most of it
shot near 9-inch or so groups.  Subsequent tests showed the ammo lots that
shot the worst had near six tenths of a grain spread in their charge weight;
good lots had only two to three tenths variation.

And last month, about 4000 rounds were made using single-stage presses
instead of the Dillon progressive loaders.  That ammo shot better than any
of the stuff made on the Dillons.  Why?  Because powder charges were thrown
from a solid-mounted measure that wasn't attached to a Dillon that reaches
vibration levels near equal to the high end of the earthquake scale.  Eight
rifles were used that shot that stuff to sub-MOA at 1000 yards.  I'm glad
the ammo was donated; I would not want to pay bulk component cost plus
even $10 per hour labor rates for that ammo; it would have been expensive.

Handloading your own ammo permits absolute control of powder charge weight.
To say nothing of being able to seat primers with a hand tool to consistant
depth/pressure; something a machine loader just can't do.

:I presume you meant to say that you can get those small groups by preping
:20 *identical* rounds within the limits above.  As long as you pick
:a load from the hundreds possible above, it will go sub half inch at 100yd.,
:though possibly to a different point of impact than a different load from
:the same set.

I don't think that's what Toby meant.

The load picked is one from a narrow range that performed well in the past.
After wearing out several top-quality barrels, folks  notice that the load
that did best in previous barrels is the same one that'll do best in the
new one.  There's no reason to try different stuff; it didn't work before so
why should it work with a new barrel.  Especially as the new barrel has the
same bore/groove/twist/chamber dimensions (within manufacturing tolerances
so darn repeatable 'tis near unbelievable), the same components/amounts and
reloading tools/processes will produce ammo that shoots just as well.  Who
cares if the zero is different?  Someone invented adjustable sights a long
time ago; getting within a quarter MOA of a new zero takes one or two shots.

Competitive shooters who produce the best scores keep on using the same
components and charge weights all the time.  That set of stuff is what works;
stuff that didn't before won't work now.  So why wear out a barrel reproving
what you already know?  Some highpower shooters still use the same component
set/quantity today as they did thirty years ago.  They've worn out two or
three barrels (~3000 rounds each) per year doing so.  Therefore, I conclude
that handloading is probably the least exciting part of really good shooting.
You use the same stuff with the same tools all the time knowing it will just
drive tacks at whatever range the ammo's intended for.  And near ho-hum
things take place when your rifle needs a new barrel; get one like you had
before and it'll do just as good with the same ammo.  In a way, this is
a good thing because it causes you to focus on the processes needed to shoot
each shot in such a way to produce a good score.  In other words, it's a
mental game where you compete against yourself and your mind's desire to
think bad thoughts which causes bad things to happen and the next shot is
embarrasingly bad.  The equipment race is over; a few things continue to
produce the best scores and that's what winners use.

To quote a Palma Team Head Coach:

    "Winners expect; losers hope for..... success in whatever they do."



BB


From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: M1A safety announcement
Organization: Hewlett-Packard Fort Collins Site

uphrrme@trex.oscs.montana.edu wrote about Mr. Perez's comments:

: Your .308 load is a bit on the hot side. I used to use IMR4320 for my first
: 1000 rounds and I overdid it. Probably why my M1A is worn now. 41.5 grains of
: IMR4064 with 210M's and 168gr bullets in a military case will produce 52000
: cup. Your commercial case will drop the peak pressure by about 4000 cup but
: your overcharge will more than jack it right back up over the maximum. That is
: more than likely why your cases only last 4 loadings and your headspace is
: gone. Did you ever put one of these blue pills in a pressure barrel? Try it, I
: bet it's over 52000cup.

I don't think those loads are on the hot side for the following reasons:

   * Sierra's manual lists 44.7-gr. of 4064 with a 168 as the max load.

   * Military teams have been using 44.0-gr. of 4064 as a standard load
     for many years in these same cases with the 168 HPMK.

   * Having seen his fired cases, they exibit all the normal, but about
     maximum presure signs.

: I use 44 grains of IMR 4064 with a 150 grain bullet. That's a 50000 cup load.

What pressure testing system/equipment did you use to measure this pressure?
I've used that same load with new cases and it's so mild, the case doesn't
go all the way back to the bolt face, but the primer does as it sticks out
of its pocket about .010 in. after firing.

: I'm switching to IMR 4895 because my Dillon powder measure likes it better and
: it goes well with 30-06 too.

All powder measures meter 4895 more uniformly than 4064.  But 4064 seems to
win most of the matches and set the records.

: At a headspace of 1.637 and only 1100rounds it's mint as far as
: I'm concerned.

The 7.62 NATO and .308 Win. headspace gages are:

   * Go     1.630-in.
   * No-Go  1.634-in.

I've seen enough head splits/separations with M118 and M852 match ammo
in chambers with greater than No-Go headspace to know that's too much.


: the published loads in the manuals are
: WAY TOO HOT. By about 5 grains in most cases. The velocities are lies too.

That's new information.  I wonder why anyone would publish information in
a loading manual that's too hot to be safe  and/or lie about the velocity
they get from what their tests show?

BB


From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: M1A safety announcement
Organization: Hewlett-Packard Fort Collins Site

uphrrme@trex.oscs.montana.edu wrote:

: Your .308 load is a bit on the hot side. I used to use IMR4320 for my first
: 1000 rounds and I overdid it. Probably why my M1A is worn now. 41.5 grains of
: IMR4064 with 210M's and 168gr bullets in a military case will produce 52000
: cup. Your commercial case will drop the peak pressure by about 4000 cup but
: your overcharge will more than jack it right back up over the maximum. That is
: more than likely why your cases only last 4 loadings and your headspace is
: gone. Did you ever put one of these blue pills in a pressure barrel? Try it, I
: bet it's over 52000cup.

: I use 44 grains of IMR 4064 with a 150 grain bullet. That's a 50000 cup load.
: I'm switching to IMR 4895 because my Dillon powder measure likes it better and
: it goes well with 30-06 too.

After some searching, I've found some .308 Win. loading data with pressure
measurements.  As `military' cases vary in weight, hence internal volume
or capacity, these loads are with case weights of about 165 to 170 grains.
Pressure test barrels were used and the pressure listed is the average of
several rounds.  Barrel length is 24 inches.

   Bullet        Charge        Powder        Average       Average
   Weight        Weight         Type         Pressure      Velocity
   ------        ------        ------        --------      --------
    150           45.0          4895          51,600        2740
                  48.5          4064          51,500        2905
                  48.5          4320          52,000        2830

    180           42.5          4895          52,000        2530
                  44.5          4064          52,200        2630
                  44.5          4320          52,200        2565

For comparison, here's the Lake City M118 and M852 7.62mm NATO Match ammo
specifications.  Note that these cases weigh about 175 grains.

    173 (M118)    42.0          4895          50,000        2580
    168 (M852)    42.2          4895          51,000        2580

And finally, the 1992 Palma Match Ammo using 166-grain cases:

    155           44.8          4895          52,800        2950 (30-in.bbl)



From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Subject: Re: Long Range Loads For M1A?
Organization: Hewlett-Packard Fort Collins Site

Try Sierra's 180-gr. HPMK with an RWS 5341 primer, about 42 grains of
IMR4064 and a commercial case such as Winchester or Federal.  Seat the
bullet about .010-in. short of the lands and single-load only.

BB

 






































































































































































































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