H4831 M1 load?

[gmg1183]

Just picked up a bunch of H4831 real cheap, and have been loading some 180gr. bullets for my Ruger bolt action.This may be a dumb question but I was wondering if anyone has heard or tried using the 4831 for the M1.
T.I.A.

[P. Greaney]

I have heard of people who have used it for their M1 rifles and they often claim without detriment.
I have never used it for the M1, nor will I ever do so.
I suggest you don't use it for your M1 either.
The burn rate falls outside that which is considered appropriate for the M1/M14 rifles.

[Tuna]

The burning rate for 4831 is far too slow for use in the M1. Port pressure would be too high resulting in damage to the operating rod. Stick
with powders with a burn rate like 4895 or 4064.

[da gimp]

Ditto on Tuna's advice.................those 2 are the perfect powders for a Garnd..... save the other for your bolt guns.

[Parashooter]

Despite the conventional wisdom - of which we see good examples above - software modeling indicates that a 100% density charge of H4831 behind a 180-grain jacketed bullet produces port/muzzle pressure virtually identical to what is predicted for a 48-grain charge of IMR4895 with a 150-grain bullet (pretty much a standard M1 recipe). In the graph below, note how the two pressure curves coincide at the tail end.



While software simulation like this isn't always an accurate reflection of actual interior ballistics, it's pretty much the best tool available to those of us who don't have a port-pressure gauge handy.

QuickLOAD's modeling also tells us this 55-grain load isn't terribly efficient, giving relatively low velocity and leaving about 13% of powder unburned* - but if economy is more important than performance, such a load might prove satisfactory for someone with a quantity of cheap H4831 available.

*Years ago I did some practical experimenting with slow powders and cast bullets in the M1. I found the biggest problem was unburned powder granules falling back into chamber and action, making an annoying mess that sometimes prevented complete chambering of the next round - with consequent slamfire hazard.

[joem]

Interesting but I'll stick with 4895.

[da gimp]

hope ya got a few extra op rods & receivers..............stick with 4064 & 4895.........ya can't go wrong. Save the other powders for use in bolt, single shot & pump guns that will love them......

[gmg1183]

Thanks for all the info Guys.

[barkerwc4362]

Port pressure

The problem with 4831 is not the port pressure, it is the duration of the port pressure. By the time port pressure for 4895 and 4064 has risen enough at the gas cylinder to force the operation rod to the rear, the pressure in the case has already started to drop allowing the case walls to lose their adhesion to the barrel chamber. This allows the rearward moving operating rod to unlock the bolt and extract the case with minimum force. This is how it is designed to operate. With 4831, by the time port pressure has risen enough at the gas cylinder to force the operating rod to the rear, there is still pressure in the case keeping the case walls adhered to the barrel chamber. This resists the rearward moving operating rod trying to unlock the bolt and extract the case. This is what bends operating rods! It is not the port pressure, but the longer duration of pressure due to a slower burning progressive powder.

Bill

[Griff Murphey]

I bought a couple of thousand rounds of reloaded '06 from Elmer Ballance with my high school graduation money in 1967. It was loaded with 147 gr. FMJs over 4831 and the rims of the Lake City match brass it was loaded into were all bent by the violent ejection. The op rod survived and is still in that rifle. But, I would not recommend 4831 - ever - in an M-1.

That was the summer I really think I learned how to shoot the M-1.

[madsenshooter]

I can't imagine the duration of port pressure having much effect, though will admit to some. How much time doe it take for that bullet to get out the barrel after it passes the port. Milliseconds no doubt. I used a load of RL19, not quite as slow, under 168gr bullets, only gave me 2450fps, but it sure was accurate. Wasn't 55gr at peak velocity, but it worked things quite well

[madsenshooter]

I've used powders as slow as RL19 with 168s. Wasn't 55gr, 51 I believe, and it was a fairly accurate load at around 2500fps. Quickload estimated 8500psi port pressure. I can't see the duration being much different in the gas system with a slower powder, there's very little difference in the amount of time before a bullet exits after passing the gasport.

[madsenshooter]

Well, now look what the board has a done, posted one yesterday, came back today and it wasn't there until after I posted again today, sorry for the double, but it should get my idea across.

[Johnny in Texas]

If I load '06 that is not M1 friendly I put in commercial boxes or plastic reload boxes to segregate it from M1 ammo.