7.62x39mm Bullets shot through .308 barrel

PO Ackley did some quite severe testing of rifles if I recall. Rechambering a 6.5 jap to .30 06 but not changing the bore and the rifle still fired without self destructing.
Not something I would do but given the time and the spare rifles I might be tempted.
 
Has anybody ever taken a slightly oversided jacketed bullet, and run it through a sizing die??? If it's really bugging you, do that. I'm sure that a Lee 308 sizing die isn't going to break the bank. I'd doubt you're going to have any problems leaving them as they are anyway. Take a vernier and open it up 0.002" and look at it. There will be an increase in pressure. No doubt about it, but I think it's going to be one of those "If you pee in the ocean, does the level go up??" deals. Of course it does, but does it make a real difference??? Not really. If firing slightly dented, slightly off center, slightly squashed bullets was going to blow up a gun, I'd have been dead a long time ago.
As for your original question. Anytime you make something tighter and ask it to slide, you're going to get increased wear. Simple mechanics. How many of these things are you planning on shooting? If it's 10,000 and you're shooting them in a $5000.00 gun, you might want to think it over a little more. If it's a few hundred to nearly a thousand....have at er.
My 2C
 
I sorry but you are a Darwin award nominee for trying this crap. You are just asking for trouble.

Like everything else, you can do this for 10 years without a problem, but 1 day it WILL bite you in the a$$!

It's just plain stupidity!
 
Anytime you make something tighter and ask it to slide, you're going to get increased wear. Simple mechanics. How many of these things are you planning on shooting? If it's 10,000 and you're shooting them in a $5000.00 gun, you might want to think it over a little more. If it's a few hundred to nearly a thousand....have at er.
My 2C

Two things.

Once a .310 bullet has moved about 1/2" (or one bullet-bearing-surface length) in the barrel, it is exactly the same size as the .308 bullet, added wear would be minimal.

And if you shoot 10,000 oversized bullets through a $5000.00 gun, I bet you don't care about a little bit of wear anyway. If you shoot 10,000 "slightly dented, slightly off center, slightly squashed bullets" through a $5000.00 gun, you might just be a gunnut....:p
 
Yes it pays to be cautious but it has been proven that in this case it causes no ill effect. Sierra state that as do RCBS. The only downside is the loss of accuracy when firing .308 through a .311 barrel.
Now No reloading company worth its salt especially from south of your border would do that unless it was lawyer tight!
So yes you are right to be cautious but in this case it has no ill effects.
 
I sorry but you are a Darwin award nominee for trying this crap. You are just asking for trouble.

Like everything else, you can do this for 10 years without a problem, but 1 day it WILL bite you in the a$$!

It's just plain stupidity!

Consider it taken under advisement. It's been more like 29 + years. Why do you use Federal primers in a Lee AutoPrime even though Lee clearly recommends against it? :) I'm guessing it's because you have a firm understanding the mechanics involved, you assessed the risk, and have made an educated decision to think outside of what you read in the manual. You then tried a few, taking every precaution possible. Eventually, after reviewing your results and possibly the historical results of others, made the decision to continue the practice. Now, after thousands of primers installed, you feel very safe about it. Who knows what will hapen 10 years from now. Hey pot, this is the kettle....you're black ;)
 
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There are certainly a lot of variables in this sort of thing. Not just the diameter of the slug, but it's hardness, it's bore contact length, and the material it's made of play a hand it how it raises pressure.
It's just not right to say that any particular over bore size is safe.
Lead bullet shooters for example shoot over bore size bullets on a regular basis. It improves accuracy in a lot of guns. But that's with lead, no jacket.
As a bullet caster, I know that different hardness, can change pressure dramatically, as evidenced on the chronograph.
Best not to mess with stuff you're not to familiar with. Particularly with a cartridge such as the 308, that is already a fairly high pressure cartridge.
 
Shooting 311" 123gr bullets in a 308 is perfectly safe unless you use pistol powder or some other big ass boo boo.

First, the diameter difference is not enough to matter. Second, the short little bullet will have a huge jump before hitting the rifling.

I have fired thousands of 308 rounds in pressure guns. Unless you load with fast powder, there is no way to boost pressure with a 123 gr bullet with 4895 type powder.

The real danger would be neck clearance. Commercial chambers have more than enough neck clearance, but many custom or match chambers are too tight. If a 311 bullet drops easily into your fired case, your neck clearance is ok. If it binds a bit, it is too tight.


But why bother? If you are pulling military bullets to load better bullets, it means you have the means to reload with the military bullets in the correct arm.

If you want cheap military bullets, buy the surplus 147 gr 308 FMJ bullets. Not very accurate, but they go bang.

My collection includes an old double barrel 8mm rifle. the barrels are made for the 318" 8mm, but have a tapered throat so the .323" bullets can be used. That is a 5 thou difference.

For plinking I use 32 Spl bullets .321"
 
Kewl thread... lots of info. So I know you guys are talking about FMJ and jacketed bullets but from the info gathered, then those neat cast bullets should be ok if run through a .309 resizer.

Haven't had any problems with a .38.357 lead bullet resized to 9mm so should be the same thing, no? But then again have to work up a load since no data for stuff like that.... :(
 
RCBS and Sierra are both reasonably "KEWL" as you put it about .308 bullets through a .311 and vica versa.
 
"...the Alleged manufacture of .308 Barrels for US made rifles in 7.62 X 39..." Alleged nothing. The Ruger Mini-30 has a .308" barrel. Always has had a .308" barrel. When it was first made in 1986, there wasn't much 7.62 x 39 ammo available Stateside. So Ruger made the rifles and had ammo made with a 125 grain .308" bullet. Now they claim their over priced, inaccurate, piece of junk will shoot Warsaw Pact surplus with the wrong diameter bullet safely. Use the right bullet diameter. The right bullet diameter for a .308 Win is .308", not .310" or .311".

I have to disagree, I have a mini 30, and it’s very accurate & reliable!
Using 7.62x39 mil. Ammo does raise the pressure some.
The only problem I find is it throws the cases about 40 ft. or more.

I followed the old .30 cal. carbine rules of minimal deflection in the bush
With the .305 diameter- 110 gr. round nose bullets using the supplied .308
Sizing die', excellent results! I would like to try 123-135 gr. round nose bullets next, (if I can find any).
I do find the mini 30 to be a great bush rifle for deer hunting.
Some provinces prohibit using a .223 (mini 14)or any other .223 for deer
I believe?
By the way, I am a gunsmith and have spent my life as a Military Weapons Tec.

Also if anyone bought the eagle 3015 10 rd. Mags. Well mine both cracked at the rivets. The company MB. Products in Hazen ND. Has not answered their phones in over three months. So forget warranty. Has anyone else had this problem with Eagle brand mags?
 
should not be a problem, higher pressure yes, but if you have a tight chamber, and tight neck then your going to have more pressure problems

is it a good ideal...... well thats up to you

I won't do it
 
should not be a problem, higher pressure yes, but if you have a tight chamber, and tight neck then your going to have more pressure problems

is it a good ideal...... well thats up to you

I won't do it

I don't think using smaller bullets will cause higher pressure, although the reverse is definatly true.
P.S. I like your post= "War is an ugly thing, but not the ugliest of things. The decayed and degraded state of moral and patriotic feeling, which thinks that nothing is worth war, is much worse. The person who has nothing for which he is willing to fight, nothing which is more important than his own personal safety, is a miserable creature and has no chance of being free unless made and kept so by the exertions of better men than himself."
-- John Stuart Mill (1806 - 1873)
So very true!!!
 
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my ruger mini 30 manual states 308 barrel and 308 to 310 bullets are safe. i have shot lots of nork yellow and silver box 310 diameter with no ill effects. 310 bullets are more accurate than 308 in my rifle.
 
RCBS and Sierra are both reasonably "KEWL" as you put it about .308 bullets through a .311 and vica versa.

Yeah, those are the ones I was thinking of. Lee makes two neat looking molds for 7.62x39 as well. Actually probably the same bullet design as the RCBS just one is a TL and the other is a regular band lubed.

RCBS are good molds but cant use the cheaper Lee handles unless you grind them down a bit so probably go for the Lee since they are cheaper and work well for the price. Since it's a 2 cavity it already comes with the handles.

Now if I can just find a good TL lube to work as good as a band lubed bullet we'd be all set.:evil:
 
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