Reloading 7.62x51 has me scratching my head

[NWSharpshooter]

Recently I picked up a couple M14s as well as started collecting 7.62 Milsurp bolt actions. I had a good supply of PPU 7.62x51 ammo, but after a couple of range trips with the PPU I wanted to try my hand at loading my own.


I have read that CCI Military primers are the same primers as CCI No 250 Large Rifle Magnum primers, and the 250s were all I could find so I picked up a 1000 pack of them, and a couple of pounds of IMR 4895.



I am loading a Hornady 150gr bullet, and the manual says that the starting load is 42.6 grains of IMR 4895.


I gave this a try and was not happy with the results. It felt like the M14 was getting beat to crap, and my case rims were bending on extraction. I tried a couple out in a K98 Mauser chambered in 7.62x51 and experienced bolt set back causing me to beat the action open.....OK so the starting load is too hot.



I headed back out to the range today with all my reloading gear and 100 pieces of sized and primed brass. I figured I would start out at 37 grains of IMR 4895 which I didn't figure would cycle the action, but figured I would start at 37 and work up until the action cycled and then I would chrony the load to see what it was running.


I loaded up five rounds and to my surprise the gun cycled beautifully. I loaded up 10 more and set up the chronograph. The ten shots were all running right around 2200 feet per second. I loaded up a couple more with 37.4 grains and they were running about 2400 feet per second. It scares me to think what they must have been running at 42.6 grains.


So my question. Should I stick to 2200-2400 feet per second and enjoy the powder savings, or should I try to get it up around 2700 fps?


Brass is PPU full length resized
Primers are CCI #250 Large Rifle Magnum Primers
Powder is IMR-4895
OAL is 2.78"
Barrel is 22" National Match Heavy Barrel

It started raining so I didn't get a chance to see how accurate these loads were at this low velocity, but I will say the action sure seemed to like them.


What say you guys? Anyone have any experience running 150s that slow?

 

[gth813x]

More power captain!

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That's why I hate reloading for semis, they're to picky and I'm worried I'm gonna blow it up

 

[Chuckdog]

I never used magnum primers when loading for M1A's I've owned. To be honest, I use Winchester LR without issue.

I'd likely try a different batch of new commercial brass and non magnum primers first. No sense in spending a fortune on premium brass, those actions will usually only allow maybe three or four safe loadings before signs of fatigue.

 

[D_Max]

Hogdon load date says 42.6 of IMR 4895, = 2630 FPS with a large rifle primer, with a magnum primer im not really sure, but im glad you found what works in your rifle. semi autos can be tough to load for sometimes

 

[$nipertime]

I would try to stay around 2650 with a 175smk . That is just me though

 

[RKC00]

There's other powders thats better in the 308. Might want to consider 748, H335, H414, 760. Better FPS with lower pressure. Or, try a non-magnum primer with the 4895. Just a thought.

 

[Smiley]

I don't load .308 for an M1A, but in my Sig 716 max load data for service rifle is mild. I don't use a magnum primer though, just a standard CCI large rifle. I've loaded IMR4895, Varget and AA2460...

 

[$nipertime]

I only use reloader 15 for 308/7.62 by the way

 

[07JKX]

May have been said, but how heavy of a crimp are you using? If light or no crimp are you sure you are to having any bullet setback on chambering?

 

[07JKX]

I am a varget fan. I load for my saiga at 43.1 grains varget. Avg vel of 2600 fps with a medium light crimp