M1 Garand Loads Using 4895, 168 gr Bullets

[slamfire1]

There are lot to lot variations in powder, so the advice of 45-47 grains of IMR 4895 is good.

For my match Garands, and in my match bolt rifle, I have used a load of 168 Match (any brand) 47.0 grains IMR 4895/AA2495 any case, WLR/CCI#34 OAL LT 3.30”

When AA2495 was cheaper I used kegs of it. There was absolutely no significant difference charge weight/velocity when compared to IMR 4895. When I called Accurate Arms, they told me the powder duplicated the pressures curves of IMR 4895. Stupidly, they call it AA2495 instead of AA4895.

I have not tested H4895 in a 30-06. In a 308 it is close to IMR 4895 but it is not identical.

In case you might have an interest in other powders, below is data with powders that are entirely acceptable in a M1 Garand. AA2520 is a ball powder and shoots very well in Garands and M1a’s. IMR 4064 does not meter as well as IMR 4895, but it is an outstanding powder and the slowest you should go in a Garand.

I never tested IMR 3031 in a 30-06, but many sources state that 3031 is the fastest you should use in a Garand. It does shoot exceptionally well in the 308 and today at the range the Club president was shooting almost touching groups at 200 yards with it in a 30-06.



M1 Garand Douglas Barrel 1:10 twist



168 Sierra Match 47.0 grs AA2495 wtd WLR FC Cases OAL 3.30"
5 May 00 T = 82 ° F

Ave Vel = 2632
Std Dev = 16
ES = 50
Low = 2616
High = 2666
N = 10


168 gr Sierra Match 47.0 AA2520 WWII cases WLR OAL 3.30"
5 May 00 T = 82 ° F )

Ave Vel = 2658
Std Dev = 35
ES = 85
Low = 2612
High = 2697
N = 5

168 gr Sierra Match 48.0 IMR 4064 wtd LC66NM WLR OAL 3.30"
5 May 00 T = 82 ° F

Ave Vel = 2594
Std Dev = 18
ES = 38
Low = 2575
High = 2613
N = 5

Two different targets, one shot in competition, the other in practice. IMR 4895 is a consistant performer. All charges were dropped, and all bullets seated on a Dillion 550B.

[Mike_Mills]

Gentlemen, here is my question. It is an important question, too.

What criteria do you use to select from amongst the various powder charges fired during load development testing? When I make up some loads using IMR4895, when it arrives, how will I down-select? How do you know what is too hot? How do you know what is too low?

Remember, I already tested 44 and 46 gr charges of H4895. That's two full grains apart. Both were good accuracy. Both cycled the rifle. Both had decent, but not low, standard deviation in muzzle velocity (SD ~ 40 fps). Neither got even close to the published velocities for their respective charge weights.

Should I use the ladder method (Audette method)? I do plan to throw the charges, not hand weigh them.

[oney]

I am obsessive compulsive, so I write everthing down, for each load I test. I usually start by picking a powder that is known for success in the ammunition I am loading. IMR 4895 and IMR 4064 are proven powders for both .308 and 30-06, and safe for use in a garand. I also like to select powders that can be used for more than one specific caliber.

I start with the lowest load data given in my manual and work up in .5 grain increments. I usually make 5 - 10 examples of each load and test them. What I am looking for when I test, is the best accuracy at the range I intend to load the round for, in the specific rifle the round will be used in, with the least amount of recoil. I also look for pressure signs ect. although this is not an exact science. I also pay close attention to the performance of a load when I duplicate what others say is their accuracy load, or what the manual gives as the best load. I try to stay away from the high end of the loading spectrum for a particular cartridge. SAFETY is the watchword for any reloader. Start at the bottom of the load and work up.

Back to the obsessive part of my thought process. It's a blessing sometimes, as well as a curse. I reload for accuracy and performance. If I'm going to take the time to reload, I take the time to make the best round I can afford. One thing I do, is I throw each powder charge short, and then trickle charge it up to the weight of powder I am seeking. Yes, it takes more time to load, and the difference it the charges I throw might not be all that great, but when I get to the line, I have no doubt that my ammunition is capable of doing what I want it to. I just have to do my part. Reloading to save money, in my experience is a myth... I do it for the accuracy I can obtain from a cartridge I loaded.

Hope this helps...

"THIS WE'LL DEFEND!"

"Life has many choices... Eternity only has two!"

[slamfire1]

What criteria do you use to select from amongst the various powder charges fired during load development testing? When I make up some loads using IMR4895, when it arrives, how will I down-select? How do you know what is too hot? How do you know what is too low?

We are discussing loading for a gas gun. One that was fielded in 1936, and taken out of service in the 60's.

You have to live within the limitations of the gas system.

The Army developed its weapon system, using pressure barrels, port pressure gages, high speed cameras, and many more unmentioned test fixtures.

I can develop my ammo looking at primers, groups, and a chronograph.

Most of my advice is subjective.

1. How does the rifle run?

When the CMP issued Federal ammo during the earlier Garand matches, they let Federal use commercial standards. The stuff was close to 2900 fps with a 150 FMJ. Lots of malfunctions happened. All over the line. The USMC (Ret) that I scored for, his Garand partially ejected a clip of seven or six rounds feeding the hot stuff they issued. Groups were not very good either.

The CMP then tested vintage ammo and told Federal to load to that velocity for the next couple of years.

So, short of blowing the receiver heel off, how does your rifle run? Are you having operating rod dismounts, misfeeds? I like having a barely perceptible clip/clop to the action. When the whole extraction/ejection/feed cycle is a big bang, I believe the load is too hot.

2. What is the case life?

Is the rifle pulling the case heads off in two reloads? Less than five? Are the rims being pulled off or ripped at an angle? These are all indications that the action is being opened before pressures have dropped in the breech to an acceptable level. Too much port pressure means the action is being opened sooner, and more violently than expected.

You will bend operating rods when the operating rod is pushed too hard. That is proof positive of problems.

3. What is the accuracy?

You will find that when you go below a certain velocity level, accuracy goes to pot. For short range shooting, find the load that runs the smoothest, shoots the best, at the lowest level. For longer range shooting, find a faster load that runs smooth and shoots good.

The rifle was designed to hum along within a limited range of energy input. It will not be happy below that level and you will be beating the components up when you exceed that level.

So Grasshopper, in time you will learn enough about the mysteries of these rifles. As you learn, your heightened level of knowledge will lead you to understand that you have become a Master and that you are able and ready to stand on your own. Then, in the fullness of time, when you meet your Buddha on the road, you can slay him , and walk past to arrive at your true destiny.

[Mike_Mills]

When I met Buddha, he turned out to be nothing more than a big hippie. So, I won't be relying on THAT method.

I've been thinking about this question this afternoon. I was hoping to just follow a pre-set recipe or just load to a mil-spec velocity. The problem is, there's no "mil-spec" for the 168 gr bullet. If, as you say, powder lots vary with this powder, I am doomed to do some load development testing of THIS lot, when I get the can.

I think I will do the Audette "ladder method" at 200 yards. I do want to throw my charges and this is the best way I know of to get to the proper powder charge for throwing because it is based up on on-target accuracy.As of now, it's probably going to be in the range from 46 to 47 gr of IMR4895.

[Maury Krupp]

I'm not as complex as some others might be.

I throw but still check each powder charge to ensure it's within my acceptable tolerance. That's more my OCD than anything else and I'm fine with that

On the rare occasions now when I do test a load all I do is make up a half-dozen or so in 0.5gr increments until I reach the recommended charge. I shoot these to see if my gun blows up. If they pass I load some more up and shoot enough to satisfy myself they're not the source of any problems on the target. Usually I'll chronograph ten shots; mostly just to satisfy my curiosity on what sort of numbers they actually produce.

I've done the Audette Method a couple times in the past. When the results came out the same as what the grey haired, gold badge and P100 wearing Masters and High Masters told me it would be I quit bothering.

A lot of cleans and match winning scores were fired by good shooters using the "industry standard" .30cal loads way back when. If those loads were good enough for them then they're good enough for me now

Maury

Edited to add:

I can't say I've ever seen any major lot to lot differences in commercial IMR4895.

Powder manufacturers have a vested interest in testing out those differences before their product hits the shelves. Reloaders don't want to re-test every time they buy a new jug; the company liability lawyers probably don't want to deal with them either.

Surplus IMR4895 is another matter. The army loaded each lot to pressure and velocity so they didn't care about any variations.

The problem I have with using blind thrown charges is more a lack of complete confidence in the throwing machinery and operator's ability to produce consistent charges.

If I'm using ball powder I'll throw and seat all day; extruded I like to check.

[PSCHMID]

In my case, I have found that 47.5gr of IMR4895 behind a Speer 168gr HPBT with appropriate standard CCI primer will give right at 2700fps and average 2.24" groups @ 100 yrds when hand-held from a bench.....group average is of six eight-shot groups.....range from biggest to smallest group was 0.49". Back off at least 2 grains to start. Don't know what if anything this may be doing to the working parts.

[Mike_Mills]

Maury, this is commercial (virgin) IMR4895.

I am sorely tempted to just go with 47.0 gr and be done with it. I can load 20 or 50 rounds and fire them for accuracy and chrono numbers. If nothing's wrong*,... I load a bunch.

* Primers and fired brass look good, SD is decent, accuracy is decent, rifle function is 100%,.. what else?

[Maury Krupp]

Maury, this is commercial (virgin) IMR4895.
I am sorely tempted to just go with 47.0 gr and be done with it. I can load 20 or 50 rounds and fire them for accuracy and chrono numbers. If nothing's wrong*,... I load a bunch.

* Primers and fired brass look good, SD is decent, accuracy is decent, rifle function is 100%,.. what else?

You can never be 100% sure what will happen with any given combination of rifle/ammo components.

That's why I'd make a few at 46.0, 46.5, 47.0. See what happens as you work your way up. Just to CYA.

If all is good I'd still probably only make a small "bunch" of around 100-200 or so for extended field testing. Shoot a match or two with them.

Once you're satisfied with the load's performance in actual use it'll be OK to crank up the progressive.

Maury

[Mike_Mills]

Well, I received my IMR powder in the mail and my new chronograph came, as well. So, I am ready to start loading. Sunday is a day at the range. I'll get my data then. It's supposed to be hot, too, almost 100 degrees. So, that's good for load testing - no surprises during the hot days of the summer.