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Hello All..
I'm pretty new to this forum, so please forgive me if this question has been addressed before.
I have some IMR3031 powder. I want to load some 165gr HPBT (sierra) bullets. I certainly don't want to screw this up. Is there a "Military equivalent" load for this powder/bullet combo? I don't want to mess with my op rod.
Thanks in advance for your expertise.
Damage to the op rod, in the context of powder selection, comes from using a powder with a burn rate slower than about IMR 4064. The pressure curves of the slower burning powders create a condition in which the bullet passes the gas port, and the gas is pushing backwards on the op rod piston trying to unlock the bolt while chamber pressures are still high enough to keep the cartridge case firmly clinging to the chamber walls. The hollow op rod is the weak link and bends if the pressures are high enough.
Most commercial ammo today, unless specifically labeled for use in the M1, is loaded with slower powders than the M1 is designed for. This is why modern 30-06 produces close to 100 fps more velocity than pre WW2 ammo.
So today, there are two choices for feeding the M1:
A Schuster adjustable gas plug, which when properly adjusted allows the use of commercial ammo as the excess gas is vented off.
Or, confine yourself to either USGI mil-spec ammo or the handloaded equivalent.
So here's where we get to the answer to your question.
Select one of the appropriate powders, (4895 is my fav, but 3031 will work just fine) and use data from a good reloading manual such as Sierra, Hornady, Nosler, Hodgdon, etc. for your bullet weight.
What you are looking for is to choose a charge weight that does not exceed the original mil-spec velocity. If the velocity is no more than USGI mil-spec, and you are using a powder appropriate for the M1, then both chamber and port pressure will be within specifications. Use a chronograph and of course follow all safe reloading practices such as starting 10% below max and work up slowly to your goal.
Here are the USGI velocities for Ball and AP.
M1 Ball and M72 Match (173gr. bullet) 2640 fps.
M2 Ball (150gr. bullet) 2740 fps
M2 AP (163gr. bullet) 2715 fps
USGI velocity figures were calculated at 78 feet from the muzzle. Add about 50 fps to approximate muzzle velocity.
And a couple of tips.
Make sure all primers are seated below flush to prevent a slam fire.
3031 is a PITA to run through a powder measure because the kernals are so large. That's why I prefer 4895. You will have to hand weigh or use an electronic powder dispenser to achieve consistent charge weights.
Don't feel that you have to load a full power load. You may find a sweet spot that is below the velocity figures cited above that cycles the gun and produces better accuracy. If you do, stop there and be happy.
Replace the op rod spring with a new one. The gun will shoot a bit softer, and cycle a bit snappier. Fulton Armory sells newly manufactured springs by one of the original contractors.
Excellent !!
If you use the search feature on this page, you'll find entire threads of information about this very subject...
Thank you for your information. It was very helpful. The reason I "chose" 3031 really wasn't a "choice", but rather a very sweet deal. I was in the right place/right time. I came across an estate sale if you will. I ended up with about 15+lbs of 3031, 5 of 4350, 500 50gr 223 sierras, 400 165gr sierra bthp, 4500 small rifle primers, 400 lg, and a bunch of other stuff for $100.
So, that's the reason for my "choice". Once in a while I manage to pull one off.
What is your favorite "starting place" 3031/165gr.?
---------- Post added at 08:04 AM ---------- Previous post was at 07:56 AM ----------
Thank you for your information. It was very helpful. The reason I "chose" 3031 really wasn't a "choice", but rather a very sweet deal. I was in the right place/right time. I came across an estate sale if you will. I ended up with about 15+lbs of 3031, 5 of 4350, 500 50gr 223 sierras, 400 165gr sierra bthp, 4500 small rifle primers, 400 lg, and a bunch of other stuff for $100.
So, that's the reason for my "choice". Once in a while I manage to pull one off.
What is your favorite "starting place" 3031/165gr.?
My Sierra manual shows 40.5gr as a starting load and 46.1 as max.
You would be safe to start at 42.0gr. and work up from there.
If you are looking to do some serious target shooting with the M1, do a search for posts on making the issue M1 shoot better.
Resist the temptation to try the 4350. It is too slow for the M1.
You'll find more info in the "Reloading for Milsurps" subforum here.
Bob
Thank you Dave.
Thank you for the info. I will resist the temptation to use the 4350. I have a lot less of it. I can use it to load for my bolt gun. I'm mostly just going to plink and maybe "defend" with the M-1, but the possibility of doing some Elk, deer, and or Oryx (I'm in NM) hunting is always on the horizon. Wouldn't that be fun? My M-1 shoots <2" groups @ 100 yards from the bench. That's plenty good enough for me, even for hunting. I just want to get as much shootable ammo loaded up "in case".
Quote:
Originally Posted by no4mk1t
FWIW; The Hornady manual (newest?) has a Garand section. Load data specifically for the M1 Garand...