Can you shoot 7.62X39 Through a 308 Barrel?

albayo

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A friend of mine wants to build something different, a single shot, or a bolt action rifle to shoot 7.62 X 39.

We talked about shooting a .308 bullet through an SKS but can you do the opposite.
Can you shoot the 7.62 X 39 bullet that is .311 through a .308 barrel or am I confusing it with .303 which is .311 to .313?

If he can what would you suggest as a good project?

Your help would be appreciated.

Thank you
Al
 
7.62x39 bullets are typically 0.310" and yes you can shoot them safely through a 308 bore. The rifling is already cutting though 10-15 thou of copper jacket with a 308 bullet, and the extra two thou has no measurable effect on pressure.
 
Yes, but it won't be the bullet that might give you pressure problems.
If you have problems (and it's very unlikely), it will be the case neck and/or the chamber throat that will give you problems.
As long as there is sufficent space for the case neck to expand and release the bullet, and as long as there is a bit of space in the leade for the bullet to start moving before it hits the rifling, you'll be just fine.

So just to make sure that if you take a fired case from that chamber, and try to put the new bullet in it. If it drops in the fired case, or slides through with very light pressure, everything will be just fine.
 
Works for me, I have a .308x39 and it shoots surplus ammo just fine. And the actions of most modern bolt actions are usually designed to operate at a good 10,000 psi higher than the x39 is loaded to, so there is a bit of a margin of safety there as well
 
I did one last year. A small BSA action one that had the .222 bbl. shot out. Took a 303 Enfield bbl (not lee-enfield)I wanted a little more wt. In lathe parted off about an inch or so droped in live round .lots of mesuring and I'm not giving away anymore tricks. Look at the front of a 303 and the 7.62X39 cart. measured, cut, mesured ,cut ,headspace checked ,threaded and gess what .Cutt bbl to 18" Crowned at 11 deg.shot well . then my brother sold it for crack.
 
So does this mean you could you put 7.62x39 through an m305?

Yes.

Where you have to be careful is neck clearance. The additional 0.002" diameter increase could be a problem if you have a minimum chamber neck. Measure the neck diameter of a case fired in your gun and compare to a sized case with a 7.62x39 (0.310") bullet inserted. You'll want 0.005"+. Less is "safe", but the absolute minimum is not much below that.
 
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you could, but you'd have to set the barrel back, re-chamber it, and tweak the gas and feeding systems. Probably not feasable, and certainly very very expensive
 
Well of course you can after all..except for euro 7.62x39s ALL .30 cal bullets are .305 when measured with a micrometer :redface:

SGTMAJSTEVE QUOTE
Your right about euro 7.62x39 ammo being .311. but take a digital caliper or micrometer and messure a .30 cal bullet. or a military 7.62 x51 bullet, you will get 7.62mm or .305, the same applies to Remington or American eagle 7.62x39 ammo
I'm a gunsmith & balistic tester. I've done it many times, I even taught it in the military as a weapons tec.


And he's a "gunsmith & balistic tester" :stirthepot2: :D
 
Well of course you can after all..except for euro 7.62x39s ALL .30 cal bullets are .305 when measured with a micrometer :redface:

SGTMAJSTEVE QUOTE
Your right about euro 7.62x39 ammo being .311. but take a digital caliper or micrometer and messure a .30 cal bullet. or a military 7.62 x51 bullet, you will get 7.62mm or .305, the same applies to Remington or American eagle 7.62x39 ammo
I'm a gunsmith & balistic tester. I've done it many times, I even taught it in the military as a weapons tec.


And he's a "gunsmith & balistic tester" :stirthepot2: :D

Fascinating! I have three different micrometers and three calipers. Also have a set of DoAll gauge blocks which can be used check the accuracy of the micrometers and calipers. I am going to measure a number of .30, and 7.62x39 bullets and see what the numbers are.
 
Fascinating! I have three different micrometers and three calipers. Also have a set of DoAll gauge blocks which can be used check the accuracy of the micrometers and calipers. I am going to measure a number of .30, and 7.62x39 bullets and see what the numbers are.

I'm a skeptic like you and I'll do the same.

Now i'm no expert (I'm just a schmuck who shoots a lot), so who am I to say, but I've never seen or heard of a 0.305" bullet. Bullets for 7.62x39 being 0.311" - sure, some 308's miking at close to 0.309" - yes. But 0.305" - I await some "proof".

I suspect he's never actually measured a 308 bullet, just "did the math" (i.e. converted 7.62mm to Imperial) and rounded the wrong way.
 
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NATO 7.62mm ball projectiles are smaller in diameter than commercial .308 bullets. This was a concern during the days when ammunition was issued for DCRA/PRA target shooting. It was not unusual for custom barrels to be tight bored and trick chambered to maximize performance; the issue ball tended to shoot not very well by target shooting standards in conventional .308 target barrels. IIRC, these tight barrels could have grove diameters as small as .3065", and the ball projectiles tended to .307". I've not heard of .305", and it will be interesting to find out.
Ganderite would be a good person to ask about this. I am sure he has forgotten more about ammunition than I will ever know.
 
New Privi Partizan 168 grn .30 cal bullets mic at 0.3083" (average for 10), Same bullets using my Mastercraft digital caliper, 0.3075" (the caliper would gain or lose 0.0005" if I opened it and closed it on the bullet again, it's a good caliper; but it's not a micrometer).

Pulled Hirtenberger 7.62x51 bullets mic at 0.3076" (only had 2), Pulled Federal 150 grn bullets 0.3077", (4),

Pulled Czhek 7.62x39 bullets measure 0.3107" (10 bullets) but were quite variable going from a low of 0.3099 to 0.3112" while all the other bullets were within 0.001" And a couple of Igman 180 grn bulles pulled from .303 Brit measure 0.3097"
 
Would a gunsmith be able to ream a .308 win chamber to 7.62x39 (.308x39) ? or would have turn it down or rebarrel completely ? I was reading about some buys in the US converting a Stevens 200 to 7.62x39 .
 
The original Ruger Mini-30 had a barrel that slugged 0.308". It fired 7.62x39 surplus ammo just fine.

The .308W barrel would have to be shortened about 1.7" and a new chamber cut.
 
Newbie so read with caution...

Would a gunsmith be able to ream a .308 win chamber to 7.62x39 (.308x39) ? or would have turn it down or rebarrel completely ? I was reading about some buys in the US converting a Stevens 200 to 7.62x39 .

Here's my take on it...

i) To convert a 7.62Nato/.308 to shoot 7.62x39 you can:
Remove Barrel, cut and re-chamber. The bore will be .308 and your bullets were designed to fit through .311 but, (internet ain't proof...) Ruger's 7.62x39 chaberings do go down a .308 bore with no issue

ii) Employ a chamber adapter (only read about but, am pursuing this option for an Arisaka 99) MCA advertised one to convert from 7.62Nato to 7.62x39. I'm exploring this option for an Arisaka 99...the adapter can be removed so you're not guilty of "bubba" work

I've been toying with the idea for a while the Ammo is just so cheap!
 
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