M1A / M14 loading questions

[ColWhitecakes]

I'm new to loading for the M1A. Although I have fired a few of my loads through it, after studying around I have found that most information suggest using rather specific powders for it, compared to using any standard powder that you might use in various other .308Win ammo. I understand that this is due to the operating system of the rifle. However, is there a general rule to follow if you use a powder other than the standard, such as those listed in the Hornady manual in the service rifle section? The reason I'm even curious is mainly because of powder availability. I do happen to have N150, which is one of those listed. But I would like to get some trigger time at mid-range with the rifle without using my stock of it up in the process. I have ARComp (which is my current powder of chose in my F-TR rifle), and also Powerpro 2000, both of which work well in .308 otherwise. I just haven't found any data specifically relating to loads for the M1a with either of these. As for the rifle, it is a Springfield national Match that I plan to feed 155gr Scenars out of Lapua brass, but I have a healthy supply of 150gr Hornady fmj and plenty of either Winchester, Remington, and LC brass that I would like to run for position and sighting practice.
Any suggestions would be appreciated

 

[smarsh361]

This is a great reference.

http://www.zediker.com/downloads/14_loading.pdf

 

[ColWhitecakes]

This is a great reference.

http://www.zediker.com/downloads/14_loading.pdf

Thanks for the link. It was very informative and helped to further answer some questions I had about this rifle.

 

[Jet]

Smarsh is right on the reference. Speer Reloading Manual #14 has data for it.

Jet

 

[Russt]

I have good results using: 43grs of Win 743.. That's with a 168 gr hpbt.

 

[FroggyOne2]

You don't want to use any powder that has a slower burn rate than Varget. If I remember right, the old go to load is IMR4064 43.2 grs with a Sierra 175 SMK.
USING SLOWER BURNING POWDERS MAY RUN THE RISK OF BENDING THE OP ROD!

Randy

 

[mac86951]

Not totally on topic, but the M172 30-06 match I read somewhere was 46.5gr IMR-4895 (mil-surplus of course) and the 173 M118 bullet. That is my default for the M1 G.

I've found that IMR-4895 or other 4895 is certainly a good place to start, as mentioned in the provided link, its good to have an old-reliable to fall back on.

One could use Quickload to get an idea on port pressures with given load changes if you need to change recipes often.

-Mac

 

[Shynloco]

You don't want to use any powder that has a slower burn rate than Varget. If I remember right, the old go to load is IMR4064 43.2 grs with a Sierra 175 SMK.
USING SLOWER BURNING POWDERS MAY RUN THE RISK OF BENDING THE OP ROD!

Randy

Randy,
STRICTLY from a learning positiion and not having any personal experience with reloading for an M1 or an M14, but having shot both rifles in my military days (seems like light years ago), how would a powder with a slower burning rate than Varget bend an Operating Rod? I'm asking because I'm curious and not trying to be cute. Those two rifles have always interested me, but my eyesight ..well. SUCKTH without a scope and thats part of the reason I never ventured down the road of buying a service rifle. Thx.

Alex

 

[bigedp51]

Below is from "Garand Gear Wesite
(slower burning powders will have higher gas port pressures)

Q: What causes an Op-Rod to get bent?

A: There are three factors that can result in damage to the Op-Rod. The first is high pressure in the gas cylinder. The second is binding of the Op-Rod, and the third is poor lubrication. If any two of the these three conditions is present then damage is possible. If the op-rod is binding then the operating rod will flex and bend when cycling until the bind is overcome. This causes the operating rod to flex and damage is possible. Our ported gas plug reduces the peak pressures in the gas cylinder, which in turn reduces the peak forces acting on the operating rod. Always check your M1 for binding by performing the [Tilt Test].

Ported Gas Plug
http://www.garandgear.com/m1garand/detail/33-springs-and-things/flypage/75-ported-gas-plug?sef=hcfp

Shooting Commercial Ammunition in Your M1 Garand
http://www.garandgear.com/component/content/article/39-m1-garand-instruction-guides/106-shooting-commercial-ammunition-in-your-m1-garand

 

[Shynloco]

Thx bigedp51. Always neat to learn new things, especiailly about rifles that I'm not all that acquainted with.

Alex

 

[tjtjwdad]

I remember an article from a NRA magazine from the 1980’s and with a M1 Garand and if memory serves me correctly, the recommended powders ranged from (IIRC) was between IMR 3031 (fastest) to H380 (slowest). Using the Lapua burn rate chart as a reference, that would exclude N150, but encompasses a several others with RE-15/H380 being the slowest and IMR3031, RE-11 and benchmark being the fastest.

WRT to op-rod issues, the M14/M1A op-rod is far sturdier than the M1 op-rod in addition the gas port is closer to the chamber whereas the M1’s gas port is next to the muzzle.

I’ve known competitors who have shot Berger 185gr bullets for years with IMR-4895 and they’ve never had a problem.

 

[FroggyOne2]

Yes that is true, but he needs to be aware of what can happen. Just like the Navy shooting those Don McCoys with the Sierra 190's.

 

[tjtjwdad]

Yes that is true, but he needs to be aware of what can happen. Just like the Navy shooting those Don McCoys with the Sierra 190's.

I should have added to the last comment; the 185gr Bergers were shot in M1A/M14 rifles. For me a 175gr is about as heavy as I would go on a steady diet.