Question about my rifle. 308.

[Rebel_Rider1969]

I have a survivor single shot. Shoots .308 great but once I tried 7.62x51 in it. Cases always got stuck and had to use cleaning rod to remove. I stopped shooting them in it, ( 3 shots, maybe) but was wondering why it would do this?? Ammo was British surplus. I never tried any other x51 ammo after that.

 

[BluesBrother]

Britain is on the metric system.

 

[Captain Dave]

Sometimes military brass is heavier (thicker) than civilian brass which reduces the available volume for propellent inside and can create higher pressures in certain chambers. It sounds like those rounds had higher pressure, which could be caused by several variables. Bottom line: If the cases stick, avoid the ammo!

 

[Baddog 0302]

Hell , you just wanted to show off the "Bambi" you killed !
Wouldn't think your chamber is that "tight".
Most military cases are loaded to 62 K psi.
What ever the reason , A really good reason to reload your rounds

 

[BluesBrother]

We are governed by physics. You can't escape it.

 

[rossi]

7.62x51 actually has less pressure than .308 Winchester.

 

[rossi]

Reb, was the Head Stamp "R G"? Radway Green.

 

[rossi]

 

[Rebel_Rider1969]

Reb, was the Head Stamp "R G"? Radway Green.

Don't remember it's been awhile back. Ammo was in bandoleer on 5rd clips.

 

[BluesBrother]

Sometimes military brass is heavier (thicker) than civilian brass which reduces the available volume for propellent inside and can create higher pressures in certain chambers. It sounds like those rounds had higher pressure, which could be caused by several variables. Bottom line: If the cases stick, avoid the ammo!

I was wondering how that happened. Less available volume, equal less propellant, equal less explosion, equal more pressure? My recommendation; don't shoot foreign military surplus ammo in commercial USA chambers and certainly don't shoot it 3 times. E=mc squared. Another rule I follow don't shoot an armature's reloads in a gun you want to keep. Just sayin'

 

[rossi]

Don't remember it's been awhile back. Ammo was in bandoleer on 5rd clips.

I'm thinking maybe that ammo was for the Ishapore Enfields that were converted from .303 British to .308 for the Indian Military. Most likely corrosive.

 

[BluesBrother]

Enfield – Ishapore manufactured 2A1 bolt action rifle, chambered in .308 Win. (7.62×51 NATO). This is not a conversion to the NATO cartridge, it was originally chambered for the NATO round. Manufactured in 1966 by R.F.I. (Rifle Factory Ishapore) in India. The factory is know for its high quality steel and these are stronger rifles that the Enfields built for the 303 Britt round.

 

[M118LR]

.308 Win and 7.62 x 51 NATO have different chamber sizes. Notice the go-no go difference. US made NATO 7.62 is crafted to .308 Win Specs. Not all NATO ammo will be crafted as such. .308 Win Go 1.630 NO-GO 1.634. 7.62 x 51 NATO. GO 1.635. NO-GO 1.6405. So NATO ammo that measures OAL of 1.635 is a GO in a 7.62 x 51 Military Chamber, but it is a NO-GO in a civilian cut .308 Win chamber. Stick with US Mil-surp or measure OAL.

 

[Captain Dave]

7.62x51 actually has less pressure than .308 Winchester.

Not always!

 

[Captain Dave]

I was wondering how that happened. Less available volume, equal less propellant, equal less explosion, equal more pressure? My recommendation; don't shoot foreign military surplus ammo in commercial USA chambers and certainly don't shoot it 3 times. E=mc squared. Another rule I follow don't shoot an armature's reloads in a gun you want to keep. Just sayin'

The pressure increase comes when the same amount of propellant used in lighter brass is used in heavier brass. As a safety conscious reloader I always weigh my brass. Sometimes I even weigh loaded rounds just to make sure I didn't make a booboo.

 

[RackinRay]

Had the same issue with the Survivor in .308. A Savage 110 in .308 handled both. I believe it is the extractor in the Survivor that was the issue, but never tried to chase it down. Ended up getting out of .308 and x51 as ammo prices were increasing.
EDIT: thinking about extraction, I decided to check case dimensions. There is a slight difference in case dimensions despite x51 being "based" om 308.

7.62×51mm NATO - Wikipedia

en.wikipedia.org

.308 Winchester - Wikipedia

en.wikipedia.org