From: John De Armond
Newsgroups: rec.guns
Subject: Re: TBird 2202 Powder Load Data for .30-06 requested
Keywords: reloading, .30-06
Date: 17 May 89 20:32:39 GMT

In article <27419@ism780c.isc.com> dirtybob@blake.acs.washington.edu
(Wendell Joost) writes:

>I have purchased about 4 pounds of Thunderbird (TCCI) 2202 powder.
>I am looking for any load data anyone might have for loading it
>into 30-06.  I am also looking for information on loading it in 7.62x39 Soviet.
>TCCI sent a sheet of loading data for .308 Winchester with specs on
>loading .308 Win with 150 grain bullets, and 40-44 grains of powder.
>My question is:
>  Is it safe to load 30-06 with the same quantity of powder and the same
>bullet weight as one would use in .308?  That is, will the excess space
>in the case cause an increase in chamber pressure?

I load EXACTLY the same powder, primer and bullet for 30-06 in my
Model 70, and .308 for my M-14 and my Shilin-barreled unlimited
class sillhoutte pistol with a 14" barrel.  I traditionally have used
IMR-4350 though I'm now experimenting with a different powder to
improve consistency in the Shilin.

It is not just for convenience that I've arrived at a common load.  I've
done a considerable ammount of chronograph and range work to arrive at
my loads.  I've found (as would be expected) that as the standard deviation
of the velocity goes down the grouping improves.

I think the problem of free space in a cartridge - if it exists at all - is
highly overstated.  Perhaps if one were using a powder that shows an
inconsistent pressure vs grains profile, there could be a problem but the
simple solution is to simply avoid that powder.

As far as your specific powder goes, I'd back off a bit from 40 grains
as a starting load.  I know nothing of this brand but most powders generate
respectable pressure at 40 grains.  Work up slowly while watching for signs -
cratered primers, difficult extraction, head expansion and so on.  IN my
experience, the .30-06 reaches maximum accuracy long before you reach maximum
pressure so that should not be a problem.  Oh, almost forgot, I use a
standard military-style spitzer boattail 150 gr FMJ bullet.  I buy them in
bulk and have had excellent results.

BTW, for working up loads at the range, I highly recommend the Lee hand-loader
press and the Lee collet dies.  The press kit is only about 30 bux and the dies
about the same.  That and a set of powder scales and you are set.  I usually
presize and prime a number of cases and then load up 5 or so at a time for
testing.  I easily operate the hand press on .308 or .30-06 cases even with
FL dies.  Highly recommended.

John

From: John De Armond
Subject: Re: Why would you shoot .308 instead of .30-06 for sniping ?
Organization: Dixie Communications Public Access.  The Mouth of the South.

scollins@milton.u.washington.edu (Richard Collins) writes:

#I have noticed that many long range bullseye competition winners use the
#.308 round.  It has been my understanding that, although not as powerful
#as the .30-06, it has a much better trajectory and tends to be more
#accurate.  I've asked some people and they say the difference in accuracy
#is from the case.  Am I just propogating a rumor here, or is what I have
#heard generally correct?  Just my $.02 cents worth.

The trajectories will be the same for similiar velocities because the same
bullet is commonly used.  The 162 gr FMJBT is a very common match round,
particularly with a hollow point.  Any accuracy improvement in the .308
(and I don't necessarily believe there is any) results from the smaller
case volume.  As a point of reference I have two model 70 match rifles,
one in .308 and one in .30-06.  The most accurate load for each involves
the same bullet, the same powder weight and the velocity of each is within 20
fps of the other.  This variation is only about twice the Standard
Deviation of the load so it borders on being statistically insignificant.

I am not a benchrest shooter so I can't delve into that that area of
esoteria.  For hunting, plinking and bullseye shooting I cannot see any
difference in accuracy.  I have begun to like the .308 because the round
is smaller, is easier to carry, is a bit easier to manipulate on the
reloading press and shoots in my silhouette pistol :-)

John

From: John De Armond
Subject: Re: .308 - .30-06 comparison
Organization: Dixie Communications Public Access.  The Mouth of the South.

reb@amc.com (Bob Brunjes) writes:

#So,if you're shooting a .30-06 for accuracy, you've got a case full of powder.
#To dispel the urban legend, the .308 is in no_ way, save bore diameter and case
#head size, "the same as" the .30-06.  The legend is a hangover from the
#introduction of the .308, which was purported to have ballistics similar to
#what the .30-06 had at _its_ introduction in 1906.  And we've come a long
#way since 1906.

#To treat .308 and .30-06 as "the same", especially with respect
#to loads,is  to invite disaster.  If you put "basically the same
#amount of powder" in your .308 loads as were in your .30-06
#loads, you run a good risk of being recognized by the rifle bolt
#protruding from your face.  DO NOT TRY THIS AT HOME!!

#For actual numbers: Nosler #1 says, with 165-grain spitzer and IMR 4350 powder,
#max load for .308 is 50 grains.  For .30-06 the max load is 57 grains.
#These loads are NOT interchangeable.

I have a real problem with the above thread considering that Bob is
posting Reloading Handbook data in an apparent attempt to contradict
reports of actual experimental data (including mine) posted here
earlier.

I am a very serious shooter.  Serious enough to have spent years and
considerable money developing loads for the specific calibers under
discussion.  Amongst other equipment, I have 2 Oehler chronos (to allow
measurment of downrange velocity and therefore to calculate REAL
as opposed to published ballistic coefficients) that have a long
history of reliable and stable service.

That said, let's look at some specifics.  Bob quotes the  Nosler
reloading manual for maximum loads.  My experience has been that
reloading manuals are at BEST, a place to start from.  For example,
my Speer manual quotes max loads of 59 gr of 4350 for the 168 gr  match bullet
and my Lymann manual quotes only 57.  Similiarly, quoted velocities
are 2978 FPS and 2824 FPS respectively.  The spread between the
three values is significant.

The reason these max values differ and are useless for the reloader is
that the data is collected from laboratory test barrels as opposed to
production barrels.  Speer forthrightly warns the reader to use the
max pressure loads only as reference materials.  My personal experience
is that the reloading manual is at best, a place to find an educated
guess as to where to start loading a totally unfamiliar caliber.

#Velocities are even more interesting.  Maximum velocities for
#the 165-grain  >spitzer are compared here in three .30 calibers.
#Data is from the Speer #7  >book, 'cause Nosler don't load no
#.30/40 Krag. (I'm not noting powders, because they're all different).

#.30/40 Krag = 2588 fps    .308 Win. = 2686 fps    .30-06 = 2919 fps

This brings me to the most important point, of course.  Maximum velocity
rarely has anything in common with the most accurate velocity.  That
is guaranteed to be the case with both the .308 and the .30-06.  For
example, the most accurate load for both my Model 70s (one .308 and the
other .30-06) is 54 gr of IMR 4350 under a 150 gr FMJBT.  This load
generates a velocity of 2587 FPS with a SD of 11 (averaged over all
rounds fired at that load to date).  A typical 5 shot 100 yd group size
is 0.4" or just over the diameter of the bullet hole.  A load of 58 gr
of IMR 4350 produces an average velocity of 2970 fps but the SD is out
to 21 and the group size is opened up to 1.5".  Notice that this velocity
is much higher than the "maximum" quoted  in any of the referenced
manuals.  Yet there is no sign of excessive pressure.  I'll add again
that both guns track so closely as to not matter.  The only difference
is that the 58 gr load is tightly compressed in the .308.

I'll also add parenthetically that the SR 4759 powder that I first started
using in my .308 and .30-30 silhouette  pistols is showing great
promise in my rifles, though I don't yet have enough data to publish.


#If you want to say a cartridge is "the same as" another, you're
#actually more accurate saying the .308 is "the same as" the
#.30/40 Krag (hey it was our military cartridge too, you know).

But if I say that they're both the same based on experience and then post
supporting data, then what?

#Now I accept the fact that, while I know of 3 .30-06s that
#shoot .75 MOA or better (~3/4" at 100 yds), a _really good_ .308
#_may_ shoot a 5/8" group.  Is that 1/8" (remember, that's 1" at
#800 yards) really worth putting up with a rimless .30/40 Krag
#for?

You consider 5/8" to be an accurate load?  Hell, my .30-30
PISTOL with a 10" barrel does better than that as I've posted
here before (though NOT with me on the trigger... yet. :-)  I
consider "accurate" in the context of .308/.30-06 to be
essentially  all bullets through one hole at 100 yds.  I can
regularly shoot 5 shots in little more than 1.5 times the bullet
diameter at 100 yards and I'm not a particularly excellent rifle
shot.

I get a real chuckle out of reading, say, 10 year old reloading manuals
or magazines where "authorities" state that accuracies seen today,
day in and day out in handgun silhouette are the exclusive purview of
the benchrest rifle.  Around here, the top tier silhouette shooters
regularly go 2 and sometimes as much as 4 banks of shootoff chickens (yep,
those tiny 50 meter chickens set at 200 meters) before one of 'em misses.

The lesson here is the reloading manuals are a good place to start and
will even give the novice or hunting reloader an adequately performing
round.  But if one wants to optimize a load, there is no substitute for
heading to the range, chrono and spotting scope in hand, and do the
grunt work.

John