Guns, Bows, Shooting Sports, and Hunting .308 vs 7.62 interchangeability?

[Radshooter]

I have a fair amount for ammo for the SKS rifles (7. 62 X 39) in storage at a remote location. I also have a fair amount of . 308 WIN for the Remington . 308 bolt action here with me. I do not have any 7. 62 here to compare to however.

I know the two rounds are the same diameter, but I was wondering if they are interchangeable between the two rifles. Are the cases the same length?

I am also going to pick up an AR-10 . 308 this weekend. Does this require any special ammo, or will the . 308 WIN work in it? Is the 7. 62 strictly for the SKS?

I thought I had this all figured out until I bought the AR-10 and now I am confusing myself.

Thanks

 

[AMink]

They are not interchangeable. The 7. 62x39 is shorter and the case is a different shape. Most 7. 62x39 is actually . 310 or . 311 in diameter. 7. 62 is usually used for the SKS and AK47 variants, though Ruger chambers the Mini 30 in that caliber. I'm sure there are many other rifles that use it, but it is still mostly a military caliber. If the AR-10 is stamped for . 308, your . 308 will work. I'm not sure, but there may be a little difference between the . 308 and the 7. 62 NATO round, just as there is a difference between . 223 and 5. 56 NATO. If you're not sure, see a qualified gun smith before making an expensive and potentially dangerous mistake.

 

[Radshooter]

Thanks AMink. That's what I thought I would hear, but for some reason the thought got stuck in my head that they were interchangeable. I was pretty sure the cases were different, but didn't have anything here to compare to. I will definitely keep them separate. I am glad to hear the . 308 we already have stashed will also work in the AR-10 as well as the Remington.

What about the 7. 62 NATO you mentioned? Is that the 7. 62 X 54? Isn't that what some Russian sniper rifles are chambered for? Is this different than . 308 WIN?

Thanks again.

Steve

 

[MoparBob]

You are probably thinking of 7. 62x51 instead of 7. 62x39 for interchangeability with the . 308 winchester. There is some controversy out there in these regards, but I personally feel it is OK to shoot 7. 62x51 out of a . 308 Winchester chambered rifle if it chambers and cycles OK. Shooting . 308 out of a 7. 62x51 stamped barrel/rifle may be a different story due to looser tolerances for the NATO chambering and higher case pressures for the . 308. A good gunsmith can easily check the headspace on a 7. 62x51 barrel and let you know if shooting . 308 will be an issue. If it is of current manufacture, you can always contact the manufacturer for guidance as well. Hope this helps.

 

[AMink]

You are probably thinking of 7. 62x51 instead of 7. 62x39 for interchangeability with the . 308 winchester. There is some controversy out there in these regards, but I personally feel it is OK to shoot 7. 62x51 out of a . 308 Winchester chambered rifle if it chambers and cycles OK. Shooting . 308 out of a 7. 62x51 stamped barrel/rifle may be a different story due to looser tolerances for the NATO chambering and higher case pressures for the . 308. A good gunsmith can easily check the headspace on a 7. 62x51 barrel and let you know if shooting . 308 will be an issue. If it is of current manufacture, you can always contact the manufacturer for guidance as well. Hope this helps.

Thanks MoparBob, I couldn't remember offhand the "x51" designation for the NATO round. If Radshooter has ammo for an SKS, it's probably a good bet it's the "x39".

 

[Radshooter]

Thanks guys. Yeah, the SKS stuff is definitely the x39 stuff. I don't have anything chambered specifically for the x51. I don't have any 7. 62 x 51 ammo period. So there seems to be no reason to get them mixed up.

Sounds like the 7. 62x51 and the . 308 WIN relation is kinda like the . 357 Mag and the . 38 Spl. You can shoot a . 38 Spl. in a . 357, but you can't shoot a . 357 in a . 38?

Thanks again... ... Steve

 

[AMink]

Thanks guys. Yeah, the SKS stuff is definitely the x39 stuff. I don't have anything chambered specifically for the x51. I don't have any 7. 62 x 51 ammo period. So there seems to be no reason to get them mixed up.



Sounds like the 7. 62x51 and the . 308 WIN relation is kinda like the . 357 Mag and the . 38 Spl. You can shoot a . 38 Spl. in a . 357, but you can't shoot a . 357 in a . 38?



Thanks again... ... Steve

Do a quick search on Google for "7. 62x51 . 308". There are a ton of hits. It appears that headspacing, tolerances, pressure, etc. are all involved and the two *can* be interchanged *maybe*. Interesting stuff if just for some more information to stuff in your head. :-laf

 

[champspa]

I have a 308 Browning lever action and a H & K military M 14 the browning will hang up every time with the military ammo.

 

[Midnite]

Sounds like the 7. 62x51 and the . 308 WIN relation is kinda like the . 357 Mag and the . 38 Spl. You can shoot a . 38 Spl. in a . 357, but you can't shoot a . 357 in a . 38?

I wouldn't characterize it like that. From what I can see on a quick Google search, the SAAMI pressure spec for . 308 Win is 62,000 psi where 7. 62 NATO is 50,000 psi. Note that the military spec is less. If you had a rifle with a relatively weak action (and I think the AR-10 action is plenty strong, though I'm not a gunsmith) chambered for the lower pressure round and tried to shoot high pressure commercial . 308 Win ammo through it on a hot day, you might run into problems.



There's a good discussion of the headspace differences here: Fulton Armory: What's the Difference between . 308 Winchester & 7. 62x51mm NATO? Scroll down to the bottom.



Mike

 

[GHarman]

SAAMI Spec. vs Government Spec. pressures notwithstanding, There are also variations in chamber and throat dimensions, gas port geometry and cleanliness of the gas system. An impluse gas system (AR-10) uses a different principle than a short stroke piston system(M-14/M1A) and requires different but necessary maintainence. I have reloaded for bolt and auoloading rifles using the . 308 and 7. 62 NATO chamber using the same lot of brass. No problems. The issues between the . 7. 62NATO/. 308 interchanceability are not as magnified as the 5. 56/. 223 interchangeability issues. The 7. 62x39 MM is a completely different animal as discussed above. This case is ~ 0. 4724" shorter than the 7. 62NATO/. 308 case and has a ~. 447" base diameter vs the . ~473"-. 475" base on a . 308/7. 62MMNATO. Just some thoughts to tickle yer synapses:-laf. GregH

 

[Radshooter]

Just a followup..... When we picked up the rifle yesterday, we also picked up a couple cases of ammo. The sign with the price on it was labeled . 308, but the boxes were labeled 7. 62. The salesman assured us they would shoot just fine in the AR-10. When we got home I eyeballed them (no calipers) next to an honest-to-God . 308 shell and they look identical in length and diameter.

Thanks again... ...