M1 Garand Mil Spec Reload Data

[Clem Paradise]

What was the military powder spec for the M1 Garand?

I have not been able to track this down and I'd like to be able to match the original military load.

I have been told, but cannot confirm, that the powder that was used is equivalent to today's IMR 4895, which is a cylindrical powder.
I've pulled the bullets from some surplus HXP (Greek) 30-06 from 1968 to 1977 and they have been loaded with 53 to 53.5 grains of a ball powder. This should be faster burning powder than the cylindrical 4895.
Hatcher's Notebook calls for a powder charge that will 'produce a muzzle velocity of 2740 fps' with no other specifics.

I'm not getting any closer to the correct information.

Thanks

[bobn]

4895, 4064. those two powders are the historically correct choices. bobn

[USSR]

I've pulled the bullets from some surplus HXP (Greek) 30-06 from 1968 to 1977 and they have been loaded with 53 to 53.5 grains of a ball powder. This should be faster burning powder than the cylindrical 4895.

Actually that HXP powder would be slower burning than IMR4895 if they are using 53+ grains of powder, otherwise the pressure would be really high. I will leave you with this axiom: Never use a powder faster than IMR3031 or slower than IMR4320, or a bullet heavier than 180 grains. IMR4895 has been the military's choice for the .30-06 since 1944.

Don

[Charlie98]

If you are trying to duplicate M1 Garand M2 ball ammo, I would start with IMR4895 and just work up to your velocity. My M1 load I've been loading for 25 years is 47grn IMR4895, a CCI #34 primer, in FC or RP brass, over any generic 145-150grn FMJ bullet, I get 2675fps out of my rebarreled Garand. IMR4064 would be my next choice.

The Hornady reloading manual has a section specifically for the M1 Service Rifle. Never base your reloading decision on what you think came out of someone else's rounds, HXP is Greek... who knows what they used.

[condor bravo]

Ninety-nine percent of those responding will say to use 4895 or its near twin brother 4064. Many prefer the 168 gr Sierra or Hornady.

[kraigwy]

The orginal military load for the '06 was 50 grs of 4895.

4895 was designed for the 30-06 military round.

Having said that, modern 4895, IMR and Hodg. isnt quite the same. Its close but I'd back off a bit off the 50 gr. mark.

Assuming a 150 gr bullet, I'd start with 47 grns and tinker with it until you find a SAFE load that is accurate in your gun.

If you go to a CMP Garand or Springfield match, walk up and down the firing line and ask about powder, you'll find 4064 is the most common followed by 4895.

Again I recommend one not ask others what works best in their gun, but ask you gun what works best in it.

[mikld]

Look in a Hornady reloading manual. There is a section dedicated to the M1 Garand with data for different bullet weights. I've had a lot of good luck with bullets in the 150-155 grain range and either IMR4895 or IMR4064 (I've tried other powders, but these two seem to work the best). Also, look at Master Po's NRA data, but I'd back that data off a full grain to start...
http://masterpostemple.bravepages.com/M1load.htm

[T. O'Heir]

The Greek stuff has steel jackets. Don't think HXP powder came from the U.S. either. Dunno, for sure. However, you can't tell anything at all about a powder other than the colour and shape of the granules by just looking at it. Spherical might be WC-846 or WC-852 or its Greek equivalent.
"...muzzle velocity of 2740 fps..." That's not .30 M2. .30 M2 ran at 2800 FPS after 1940. .30 M1 with it's 174.5 grain bullet ran at 2700 FPS.
"...its near twin brother 4064..." Nowhere near twins or even related. IMR4064 gives much more consistent accuracy than IMR4895. IMR4895 burns faster too.

[F. Guffey]

if I wanted to know I would call Hodgdon, I have 30/06 loaded rounds that are bundled in groups of 8, when the bolt is open the little bundles fit the M1 Garand, most of them are armor piercing, I am told they did not can armor piercing enblock clips but who knows?

I like the smell of newly opened ammo cans with new cardboard dividers.

F. Guffey

[Unclenick]

Clem,

The ball powder used by LC in later M2 was WC852. It is sold in canister grade by Hodgdon as H380. Unfortunately, the military's bulk grade version of this powder came in two substantially different burn rates. Indeed, this burn rate chart actually has two listings for the surplus bulk grade at positions 203 and 226, it was so different. The former required about 53 grains to reach M2 velocities, while the latter took more like 57 grains. The latter was too slow, making too much gas port pressure for the Garand's long, slender op-rod, but not wanting to surplus out the powder lot, the military made up a bunch of M2 with it that was qualified only for use in machine guns.

I have some of that machine gun M2. You can tell by the stripper clip marks on the cases and I have pulled down a good bit and changed the powder and bullets out to get better accuracy and spare the op-rod. The DCM, apparently unaware of this problem, issued this for the Garand, and while I don't know of an op-rod wildly bent by it, I am sure it was shortening life a good bit.

Several points about loading for the Garand:

People forget that modern electronics and high-speed counters didn't exist when the military was developing M2 ball for the .30-06. The slower vacuum tube electronics systems of the day needed more time to get the bullet's speed accurately. The timer start coil was at 6 feet from the muzzle and the stop coil was at 150 feet. The average of those two distances is 78 feet, so you will note the velocity data for the .30-06 is given as accurate at 78 feet, at which point it will have lost a little over 60 fps. So if you are measuring near the muzzle, that velocity number does not quite copy the original ammo. On the other hand, it must be born in mind that the velocity was measured coming out of a test barrel that is made to minimum specs and is carefully loaded so the powder in the case is falling back over the primer (it's maximum pressure and velocity position). You cannot expect your Garand to produce that same velocity. You need a different way to figure it out.

Here's what I did: First, some time ago I went through the M2 Ball ballistics data and found the bullet shape was best modeled by the G6 reference projectile, not the standard G1 projectile. It comes closest to providing all the right bullet drops and the right extreme range when you use a G6 BC of 0.212 from muzzle to the terminal point. If you use an exterior ballistics program that allows the G6 drag model, that will give you the most accurate results for that original bullet (flat base, 7 cal tangent ogive, weight of 152 grains maximum with a -3.0 grain tolerance). The free calculators at the JBM Ballistics site allow this. If for some reason, you need the older standard G1 BC, it is about 0.387 over the first 100 yards. It drops off to 0.330 at 1000 yards because of the G1 projectile's drag curve shape mismatch. I have attached a PDF file of my work on this, with pretty complete lists of G1 BC v. range and velocity correction tables for the M2 bullet as well as sight come-ups for different muzzle velocities.

The second thing I did was use Hodgdon's published data for the 150 grain Nosler Ballistic Tip bullet. It won't be exact, but it's as close as we are likely to come without investing in a test barrel. They use a 24" pressure test gun, as does the military. The only difference is the military measures gas port pressure as well as chamber pressure. They have 150 grain bullets (close enough) and 15-foot velocity results (the SAAMI standard screen mid-point). From that, I can tell you what their test powder charge would be to get to military MV with the 150 grain Nosler bullet. This is easy because the number of fps/grain of powder is very linear within the published load range and even a short range outside it. So, velocity v. charge is a straight line within that range for all practical purposes.

Some data (note that this is all close to or slightly below published data for the closest bullet weight):

To go 2740 fps at 78 feet (26 yards), the M2 ball bullet needs a muzzle velocity of 2801 fps. At 15 feet (SAAMI chronograph distance) it will measure 2794 fps from a minimum chamber test barrel. Plugging 2794 fps into the straight line fit we get:

H380 -> 52.9 grains (just under their 53-grain minimum load, but is within dispensing error range. This is the faster WC852, so it should be OK in the Garand.

IMR 4064 -> 48.1 grains (This is about 1/4 of the range above the starting load).

IMR 4895 -> 47.4 grains (This is below Hodgdon's starting load of 49 grains, but is a typical Garand load charge weight).


Note that Hodgdon uses a Winchester LR primer. H380 is likely to work best with a magnum primer, like the CCI #34. This is because it is both harder to ignite and running at the low end of its pressure range. Note, too, that Hodgdon uses reference powders for testing. The lot you buy may be off on burn rate by a few percent, so, as always, work the loads up carefully.

If you want to use slower powders in the Garand, you need to use a modified gas plug. I like this one, as you don't need to adjust it. Just shoot.

I have a PDF file of 100 yard reduced sighting targets showing where POI for several loads would land at 100 yards when your sight come-ups are correct. Note that the 600 yard target is two pages that have to be joined after printing.

[RC20]

A lot of great information.

And even better, practical real world to use loads.

[44 AMP]

For what its worth, some of the information given in Cartridges of the World (3rd edition)

Cartridge, Caliber .30, Ball M2
Velocity: 2740 +/- 30 ft/sec at 78 feet
Pressure: 50,000psi max avg

Propellant: IMR 4895, 50 gr
WC 852, 50 grs
CMR-100, 45gr

Identification: Plain Tip

[USSR]

Cartridge, Caliber .30, Ball M2
Velocity: 2740 +/- 30 ft/sec at 78 feet
Pressure: 50,000psi max avg

Nope. Just because the US military lists the specs at 50,000 PSI, you cannot assume that it was measured by the piezo gauge that SAAMI uses for its specs. ALL pressure gauges in the US read in PSI, because that is the standard. In the 1960s, SAAMI and the reloading industry got together and agreed to list PSI values measured by the copper gauge as CUP. The US military standards predate this agreement and the military doesn't care, so they just list the pressure as PSI without indicating that it is a copper crusher measurement. If the maximum pressure was really 50k psi, the .30-06 would be very similar to the .30-40 Krag in power. The site that this info came from has other errors as well. The true maximum pressure for the .30-06 is 50k CUP and 60k psi.

Don

[Unclenick]

Funnier still, if you look up a link to member FALphil's article on 7.62 NATO vs. 308 Win, his brother worked for the Aberdeen Proving Grounds artillery munitions lab and said all the techs there used CUP when SAMMI started to, but the tech manual editor's did not and stayed with psi. This may have been influenced by the fact NATO and the CIP used the same pressure units for crushers and channel transducers, also relying on the reader to know which pressure measuring system was employed. In fact, you have to read the specification for a particular round to find that measuring system information put down in print.

The load data in the tech manuals is also of dubious accuracy. They put M2 at 50 grains of 4895, but also put the charge behind the 173 grain M72 match bullet at that same 50 grain value of 4895. I have a sheet of loads from 1957 to 1966 of National Match loads with 4895 by year, and they range from 46 grains to 48.5 grains, depending on the powder burn rate that happened to have been produced at the time. It is possible they had a lot so slow that 50 grains was actually used at some point in M2, but it would not have been the case for powder of the faster rate they had in some years, nor for the more tightly controlled burn rate powder in the canister grade sold to handloaders today. Indeed, the military ammo specs specify a peak pressure limit, a gas port pressure window, and the velocity window mentioned earlier, and extreme temperature functioning. No powder or charge weight is mentioned as any powder that produces the required performance within the specified limits would be acceptable, and actual production charge weights for each lot would be determined by reaching those values with it.

[Road_Clam]

My go to 150 gr fmjbt load is 48.5 gr of 4064 and HXP or SL cases. I'm at about 2760 fps, and shoots about 2.5 moa at 100 yds off a precision rest and a rear bag with an optic. While the Hornady manual does list a dedicated M1 section, there's no 4064 data with the 150 gr fmjbt bullet.

[USSR]

I have a sheet of loads from 1957 to 1966 of National Match loads with 4895 by year, and they range from 46 grains to 48.5 grains, depending on the powder burn rate that happened to have been produced at the time.

I have that same National Match Load Data, Unclenick. In fact, I pulled down one of my 1965 Match cartridges and , Yep, 46.5 grains just as they said.

Don

[Unclenick]

USSR,

Yep. I have several boxes of 1964 and confirmed by pulling that they average 46.0 grains, as stated in that data.


Road Clam,

Yes, that's a reasonable sounding velocity from a real gun rather than a test barrel. Test barrel MV would be about 2809 fps at 15 ft. I tested some of the above-mentioned 1964 NM ammo in our club Garands one time and found velocity ranged from about 2610 fps down to 2495 fps, depending on the gun and whether or not the powder was over the primer or the bullet. That latter factor alone made about 80 fps difference and turned the primers from rounded (powder forward; lowest fps) to fairly flat (powder over primer; highest velocity). The Garands loading cycle tends to throw the powder forward if you are shooting it level. That velocity factor is why SAAMI test standards have the ballistic technician handle the cartridge so as to get the powder over the primer when the powder space in the case is not 100% full.