.308 Winchester/7.62mm nato not the same.

B9mmHP · September 17, 2000, 05:31 PM

They differ in the length and angle of the shoulder of the cartridge.
And since I have already fired a few hundred rounds of the 7.62mm nato through my M14 .308 and it has`nt come apart I guess they can be interchangeable?
I need some pro advice.
Thank you.

Hutch · September 17, 2000, 06:55 PM

I think the external brass dimensions are identical. Military (7.62) ammo has thicker walls, leading to reduced case volume. The SAAMMI(sp?) specs for working pressure may be different, but I'd bet my mortage the cartridges have the same dimensions.

Now that I've thunk some more, you ARE taking about the 7.62x51mm NATO round, correct?

[This message has been edited by Hutch (edited September 17, 2000).]

Steve Smith · September 17, 2000, 07:08 PM

Read the info at www.fulton-armory.com and it'll help. Typically, you can shoot 7.62 NATO in a .308, but not always.

beemerb · September 17, 2000, 10:39 PM

Same round!!!!!Brass thickness will vary but external dim are the same.Totaly interchangeable.

------------------
Bob--- Age and deceit will overcome youth and speed.
I'm old and deceitful.

Patrick Graham · September 18, 2000, 08:08 PM

The internal case capacity of Lake City brass is less than commercial Winchester 308 brass. The Mil spec brass is slightly thicker. That's why "They" (reloading manuals) always say to back off the load 10% for military brass.

Big Bunny · September 19, 2000, 05:59 AM

I think the Nato round may well be loaded "up" quite a bit(typical milspec!)and sized a bit smaller in diam and shoulder so it has no chambering problems in all conditions/dirty chambers etc. But for our purposes they should be interchangable in most SSAMI spec guns, I have 3x 7.62x51mm and have no problems interchangabitity so far.... but there is always the exception....I suppose!

------------------
If we shooting sportspersons don't hang together... we will all hang separately !
Never knock another's different shooting interest or discipline...REMEMBER we are all but leaves on the same tree of freedom.

Art Eatman · September 19, 2000, 08:12 AM

For all practical purposes, there ain't no difference. Many reloaders use small-base full-length resizing dies, but that's to ensure reliable extraction in semi-autos or in MGs. When using new, "store bought" ammo, don't worry.

No mil-spec load is hotter; there ain't no magic in military steel. The hotter the load, remember, the less reliable the extraction in SAs and MGs. The idea of "hot loads" for military cartridges is due to the 9mm Para, where the full-auto guns are indeed stronger than handguns. Even there, the pressures are much, much lower than for rifle cartridges...

FWIW, Art

Big Bunny · September 19, 2000, 10:07 PM

Art ...I beg to slightly differ -we find that the Aus 7.62mm milspec ammo(and 6.5x55mm swede too -incidentially) here IS fairly "hot" by our sporting and target reloading standards especially in hot conditions over 30 deg C, but the thicker cases can stand it and interestingly the aussie mil 7.62 mm rounds are never reloaded . Use of these rounds are now confined to the GPMG M60 - as the normal service round is now 5.56mm Nato.
The "Z" 9mm SMG round has been obsolete for 5 to 10 years, but it has also used in the Browning HP, still on issue and I agree it was 'over the top' in blast and felt recoil at around 1,350fps!
Interestingly and to further expand on my theme of some milspec ammo being variable in pressure etc, the British made .303BR Mk7 is a lot milder than the Greek Mk8, which was designed for Vickers MG and aircraft use. [So we do not recommend a steady diet of this Mk8 ammo in SMLE rifles of #1 variety for obvious reasons!]
So oils arn't always oils!
I feel it pays to be careful with "foreign" ammo in milspec of that country. A bargain may not always be so IMHO

------------------
If we shooting sportspersons don't hang together... we will all hang separately !
Never knock another's different shooting interest or discipline...REMEMBER we are all but leaves on the same tree of freedom.

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September 17, 2000, 05:31 PM	#1
B9mmHP Senior Member Join Date: February 2, 2000 Location: Texas Posts: 465	They differ in the length and angle of the shoulder of the cartridge. And since I have already fired a few hundred rounds of the 7.62mm nato through my M14 .308 and it has`nt come apart I guess they can be interchangeable? I need some pro advice. Thank you.

September 17, 2000, 06:55 PM	#2
Hutch Senior Member Join Date: February 12, 2000 Location: Birmingham, AL Posts: 1,124	I think the external brass dimensions are identical. Military (7.62) ammo has thicker walls, leading to reduced case volume. The SAAMMI(sp?) specs for working pressure may be different, but I'd bet my mortage the cartridges have the same dimensions. Now that I've thunk some more, you ARE taking about the 7.62x51mm NATO round, correct? [This message has been edited by Hutch (edited September 17, 2000).]

September 17, 2000, 07:08 PM	#3
Steve Smith Senior Member Join Date: December 9, 1999 Posts: 4,131	Read the info at www.fulton-armory.com and it'll help. Typically, you can shoot 7.62 NATO in a .308, but not always.

September 17, 2000, 10:39 PM	#4
beemerb Junior member Join Date: October 2, 1999 Location: AZ Posts: 1,759	Same round!!!!!Brass thickness will vary but external dim are the same.Totaly interchangeable. ------------------ Bob--- Age and deceit will overcome youth and speed. I'm old and deceitful.

September 18, 2000, 08:08 PM	#5
Patrick Graham Junior member Join Date: January 18, 1999 Location: Kokomo, Indiana USA Posts: 674	The internal case capacity of Lake City brass is less than commercial Winchester 308 brass. The Mil spec brass is slightly thicker. That's why "They" (reloading manuals) always say to back off the load 10% for military brass.

September 19, 2000, 05:59 AM	#6
Big Bunny Senior Member Join Date: August 9, 1999 Location: New South Wales - Australia Posts: 605	I think the Nato round may well be loaded "up" quite a bit(typical milspec!)and sized a bit smaller in diam and shoulder so it has no chambering problems in all conditions/dirty chambers etc. But for our purposes they should be interchangable in most SSAMI spec guns, I have 3x 7.62x51mm and have no problems interchangabitity so far.... but there is always the exception....I suppose! ------------------ If we shooting sportspersons don't hang together... we will all hang separately ! Never knock another's different shooting interest or discipline...REMEMBER we are all but leaves on the same tree of freedom.

September 19, 2000, 08:12 AM	#7
Art Eatman Staff in Memoriam Join Date: November 13, 1998 Location: Terlingua, TX; Thomasville, GA Posts: 24,798	For all practical purposes, there ain't no difference. Many reloaders use small-base full-length resizing dies, but that's to ensure reliable extraction in semi-autos or in MGs. When using new, "store bought" ammo, don't worry. No mil-spec load is hotter; there ain't no magic in military steel. The hotter the load, remember, the less reliable the extraction in SAs and MGs. The idea of "hot loads" for military cartridges is due to the 9mm Para, where the full-auto guns are indeed stronger than handguns. Even there, the pressures are much, much lower than for rifle cartridges... FWIW, Art

September 19, 2000, 10:07 PM	#8
Big Bunny Senior Member Join Date: August 9, 1999 Location: New South Wales - Australia Posts: 605	Art ...I beg to slightly differ -we find that the Aus 7.62mm milspec ammo(and 6.5x55mm swede too -incidentially) here IS fairly "hot" by our sporting and target reloading standards especially in hot conditions over 30 deg C, but the thicker cases can stand it and interestingly the aussie mil 7.62 mm rounds are never reloaded . Use of these rounds are now confined to the GPMG M60 - as the normal service round is now 5.56mm Nato. The "Z" 9mm SMG round has been obsolete for 5 to 10 years, but it has also used in the Browning HP, still on issue and I agree it was 'over the top' in blast and felt recoil at around 1,350fps! Interestingly and to further expand on my theme of some milspec ammo being variable in pressure etc, the British made .303BR Mk7 is a lot milder than the Greek Mk8, which was designed for Vickers MG and aircraft use. [So we do not recommend a steady diet of this Mk8 ammo in SMLE rifles of #1 variety for obvious reasons!] So oils arn't always oils! I feel it pays to be careful with "foreign" ammo in milspec of that country. A bargain may not always be so IMHO ------------------ If we shooting sportspersons don't hang together... we will all hang separately ! Never knock another's different shooting interest or discipline...REMEMBER we are all but leaves on the same tree of freedom.