.311 down .308 bore


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sonier
August 10, 2010, 02:47 PM
question is, can you run .311 diameter through a .308 bore. I think the mini 30 series has a .308 bore but will shoot surplus .311 bullets.

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rcmodel
August 10, 2010, 02:52 PM
Apparently.

All of the surplus Rusky & Chinese ammo is .311" and I don't know that Ruger has warned against shooting any of it.

rc

R.W.Dale
August 10, 2010, 02:53 PM
The very first run of mini 30 rifles had a .308" bore but the also had a long tapered throat to facilitate firing .310" bullet factory loads.

Mini's made since the mid 90's have the "proper" bored barrel for 7.62x39mm

All and I mean ALL commercially loaded 7.62x39 uses .310" bullets, No matter where it was made

sonier
August 10, 2010, 02:58 PM
well im pulling about 250 7.62x39 rounds, I finally got a puller to get this old surplus junk that i dont have a gun to fire it with. My calipers have been out a while, but if i recall they were .3105 diameter bullets. Im going to prolly start some light 30/06 loads and see how they do.

ranger335v
August 10, 2010, 03:00 PM
P.O. Ackley ran a series of experiments in the late 40s, early 50s and proved we can run 8mm/.323" bullets through a .308 bore if the chamber neck is bored large enough to take the loaded round without being jammed.

W.E.G.
August 10, 2010, 03:00 PM
http://www.perfectunion.com/vb/showthread.php?t=40813
According to Ruger, post 1993 barrels are .310 to .311 and do not taper down to .308 at muzzle.

Mini-30 owners shoot .311 diameter Russian el-cheapo ammo in their Mini-30's all the time.

sonier
August 10, 2010, 03:05 PM
is there any test from ackley running those 323 diameter, id like to know the results

rcmodel
August 10, 2010, 03:18 PM
Ackley did a lot of things like that.
It was done to prove it would not automatically result in a KaBoom.

He wasn't trying to suggest we should all run out and do it too.

The problem with most all of Ackleys testing was, he did it before affordable pressure testing methods were available to him.

So all he knew for sure was the case didn't fail, and the action didn't blow up.

rc

sonier
August 10, 2010, 03:20 PM
well ive read about a lot of people using .310 .311 diameter bullets in .308 bores. I havnt read one bad thing so far, but knowing my luck i would be the first to screw somin up lol

ScratchnDent
August 10, 2010, 04:07 PM
I'm as frugal as they come, but saving $25 on a box of properly sized bullets isn't worth risking my gun and my hands and face.

sonier
August 10, 2010, 04:28 PM
well I got an update I pulled the 125 grain .310 bullets I then loaded them in a 30/06. I put a min charge of 54 grains with IMR 4320, the necks of the casing had soot, but this is also a remington 740 so it is gas operated. The primers seemed to be really flattened out, no primer flow or piercing. also no extraction marks on the case head.

sonier
August 10, 2010, 04:51 PM
Ok i have had the chance to work up a few loads, i was able to get to about 56.0 grains of IMR 4320 before I started to see extractor marks, but far as safe wise, I am not getting any other pressure signs than normal. Normal load data seems to just fine as well.

I dont have the liberty of just buying bullets whenever, I dont have a credit card, im 19 and my job dosnt pay that well to go buy whatever I please. This also was to see if it could be done safely, who knows one day we might be short of .308 diameter and need to find alternatives. I have a mosin nagant I can reload for so the majority of these pulled bullets will go to that rifle.

ranger335v
August 10, 2010, 06:42 PM
"He wasn't trying to suggest we should all run out and do it too."

Nor was I

"The problem with most all of Ackleys testing was, he did it before affordable pressure testing methods were available to him. So all he knew for sure was the case didn't fail, and the action didn't blow up."

I believe that was all he concluded from the effort. He did have to bore the throats out so the necks weren't crimped, so few of us could do it if we tried.

Ackley's and my point was/is that the bore diameter itself isn't all that critical. If Mr. Sonier's cartridges will chamber with room for the neck to expand and release his .311 bullets they will easily run through his .308 bore. In fact they will be .308 when they've traveled their own length.

sonier
August 10, 2010, 07:46 PM
they chambered very easly, no difference at all from normal .308 diameter rounds.

TonyT
August 10, 2010, 07:52 PM
I would not shoot oversized jacketed bullets but I did load very mild loads of 32 S&W Long with 98 gr. LHBWC's 0.312" in a custom 0.308" barrel using my Walther GSP pistol.

sonier
August 10, 2010, 07:58 PM
I deffinately would not advocate everyone star using .310 jacketed rounds. It msot liekly will cause early barrel ware. I did find that I can load oversized jackets in MY rifles with no problems. I tested 3 different 30/06 rifles.

Sport45
August 10, 2010, 09:42 PM
I ran quite a few of the 123gr AK bullets (.310", I think) through my Garand back when we could buy them for about $30 a thousand.

ranger335v
August 10, 2010, 10:01 PM
"It msot liekly will cause early barrel ware."

Virtually all bore wear comes from burning powder errosion, not bullet friction.

HOWARD J
August 10, 2010, 10:32 PM
Last e-mail from Ruger: go ahead & shoot 311 in any Mini-30---no problem.
I've been doing it for years on my old Mini-30---it still shoots great.

sonier
August 10, 2010, 10:59 PM
Im thinking of a new wildcat, 7.62/06 30/06 necked up to .310 diamater ;)

AF FAL
August 11, 2010, 01:54 AM
I have a custom mini 30 with a true .308 SS heavy barrel. I shoot .310-.311 through it when I need more brass for reloading (I only use IMI for for 7.62x39). Never had any issues, only thing I've run across is a bit of increased copper fouling.

For those with stock mini's the bores have been .310 or .311 for the better part of 15 years or so that I know of.

sonier
August 11, 2010, 02:08 PM
Im not seeing any problems with bullets being slightly larger than the bore, maybe increase barrel wear, but that is just a theory.

R.W.Dale
August 11, 2010, 02:15 PM
Im not seeing any problems with bullets being slightly larger than the bore, maybe increase barrel wear, but that is just a theory.
, but this is also a remington 740

If you're shooting a 740 you're gonna wear out the bolt, action bars and receiver by merely shooting the thing with any ammo long long before you get to see any bore wear crop up from .310" down a .308"


I built a custom stevens200 bench gun on a shilen .308" barrel and shot well over 700rds of .310" bulleted factory ammo through it with no reduction in accuracy for my handloads

RyanM
August 11, 2010, 02:26 PM
I really doubt that .310 in a .308 will cause any barrel wear. It might bump up the pressure a little though, as the bullet swages down a hare, and ends up with a longer than intended bearing surface, but that's about it.

.308 in a .310, on the other hand, will cause bore erosion unless the bullet is soft enough to obturate and seal the bore, as gas will blow past the bullet otherwise.

sonier
August 11, 2010, 02:42 PM
that was one problem i noticed, in both my savage model 111 and remington 740 the neck of the case kept getting gas blowback around the neck of the case. It seems the case would not seal properly in the gun. I worked up to near max loads and still had the same problem.

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