7.62x51mmNATO case sizing Questions

01 April 2006, 02:09

Hello! New to this forum as well as reloading. I was hoping to receive some informed responses.

The rifles I am looking to reload cases for are chambered for 7.62x51mm NATO. Although many online vendors may advertise some 922(r) military styled semi-autos as .308, they are not.I will assume on this forum that you gys know all about the differences

So I have a question regarding sizing dies. Most of the sizing dies being sold from online reloading outlets are listed as .308. The .308 cartridge has different tolerance dimensions than the 7.62x51mmNATO. So here are my questions:

If I size 7.62x51NATO brass using .308 case sizing dies, will this be essentially reforming the brass to .308 dimensions? Would this lead to potential safety problems if a rifle was pushing the "No-Go" range on a 7.62x51mm Headspace Gauge?

Is there a 7.62x51mm sizing die?

Thanks,

-Thed

01 April 2006, 02:23

Fjold

Here are the differences:

.308 Winchester chamber headspace gauges:
GO: 1.630"
NOGO: 1.634"
FIELD REJECT: 1.638"

US Army 7.62x51 chamber headspace gauges:
GO: 1.635"
FIELD REJECT: 1.6455"

SAAMI .308 Winchester chamber pressures:
MAP: 62,000 psi
MPSM: 66,000 psi
Minimum Proof Pressure: 83,000 psi
Maximum Proof Pressure: 89,000 psi

US Army 7.62x51 chamber pressures:
Maximum: 50,000 psi
Proof pressure: 67,500 psi

7.62x51 NATO pressure data from: TM 43-001-27 "Army Ammunition Data Sheets Small Caliber Ammunition" and headspace data from Kuhnhausen's M1/M1A shop manual

.308 Winchester data from ANSI/SAAMI document Z299.4-1992, "Pressure and Velocity, Centerfire Rifle Sporting Ammunition"

The Remington Arms Company specifically advises that military 7.62x51 NATO ammunition *not* be fired in any of their rifles chambered for the .308 Winchester, due to the more lax manufacturing specifications used on the NATO.

Resize your brass to fit your bolt rifle's chamber or full length resize your ammo for your semi-auto with the 308 dies, they won't hurt anything.

Frank

"I don't know what there is about buffalo that frightens me so.....He looks like he hates you personally. He looks like you owe him money."
- Robert Ruark, Horn of the Hunter, 1953

NRA Life, SAF Life, CRPA Life, DRSS lite

01 April 2006, 08:59

Geo.

You can buy dies from Forster that are made to NATO 7.62x51 specs. Not a problem, just give them a call. Most retailers will not have them and many will not even know what you are talking about. Sinclair might have them.