I have a VEPR K in 7.62x39, modified Bulgarian gas tube, BSA Platinum 8-32x44 telescopic sight, Harris Bipod, and a variety of ammo.

I shot these at 50 yd and averaged my groupings:

Winchester White-Box 123gr FMJ
1.1875"

Barnaul 122 gr JHP
1.31"

Federal American Eagle 124 gr FMJ
1.56"

Wolf 154gr PSP,
1.67"

Wolf 122gr FMJ
2.55"
Note that I had one 3-shot grouping measuring 0.65" at 50 yd using Wolf 122gr FMJ. This is VERY inconsistent ammunition.

The most consistent ammo happened to be the Barnaul JHP and Winchester white box.

I hope these figures are of some use to everyone.

I found Wolf to give the most inconsistency in grouping. I had one 0.65" grouping with Wolf 122gr FMJ, but the next grouping was like 4". I noticed the same inconsistency in Wolf 154gr PSP... this stuff was one of the best Wolf cartridges in 7.62x39 that I have shot. It would give me decent groupings but sometimes they'd go all over the place.

Usually the first 2 shots that hit the paper are very close together (within 1-2mm) and the third would give me the most extreme variance in POI. Most of my 3-shot groups would have been sub-0.5" if I counted them as 2-shot groups, but then it wouldn't have been a 3 shot group HP
I'm thinking about buying Federal Hi-Shok and Remington UMC to test since they weren't covered in your test, but I don't think anything will beat or get close to Barnaul in terms of price range and consistency.

Once I get more results I'll post them.

Check this thread and you will see why the inconsistant results of you shooting Russian ammo.
www.jobrelatedstuff.com/forums/topic.html?b=4&f=80&t=62850
Don't waste your time testing  Remington or UMC ammo unless you can get some that was made this year. Remington just came out 3 months ago with .310" bullets sold as componets for reloading 7.62x39mm. So I assume they will start using them in there loaded ammo also. As all the Remington and UMC 7.62x39mm ammo I have checked since they starting making it was loaded with bullets that measured .308".
The under size bullets in their factory ammo resulted in 6"+ groups at 100 yards.

JA545:

What type of ammo was that? It looks like the Barnaul box but it was made by Uly???

Barnaul was always sub-2" ammo at 50 yd for my rifle.. more like 1.25" max. It was very consistent stuff but not tight enough.

You said you used 125 gr Sierra bullets? Is that the 125gr SP?

I did not have my Starret Micrometer or any other precision instruments at hand to measure the bullets other than my Mitutoyo caliper.
Wolf FMJ measured 0.305 - 0.308" nothing more.
Skip Remington UMC and Express? Thanks for the tip! Do you have any more?
Federal American Eagle 124gr FMJ is ~0.310" as is Winchester USA (White box) 123 gr FMJ.
Barnaul JHP appears to be a 0.310" bullet as is Wolf 154gr SP (well, the pre-03 stuff with the lacquer cases at least).

What about PMC Bronze, Winchester Super-X, and Corbon JHP and JSP?

I'd be willing to pay extra bux to try the more exotic ammo in 7.62x39 if someone else has not already done so. Corbon is about $0.80/rd USD which is like 10 times the cost of Wolf FMJ.

Just FYI, my Russian VEPR K barrel/chamber does NOT produce those crimps near the neck of the case. It was made in 2003. I have shot over 700 rounds and all of the spent cases look "normal". Then again, wasn't Molot one of the state manufacturers for military RPK rifles? Maybe they used military chambers for all their VEPRs?

I was thinking... maybe they used the smaller 0.305-0.308 bullets in the winter time or in bad environments?

If the bullet was JUST RIGHT in the fitment (as well as the case neck fitting into the chamber) at 50F+ in dry/clean conditions... then if it were subjected to extreme cold (-40 degrees) or dusty/sandy conditions, one might experience a malfunction of their rifle... Now with a smaller bullet, the chamber could contract and not interfere with the case neck, and the smaller bore wouldn't be a tight squeeze for the bullet. Sand/grit could also fit in with the bullet allowing normal operation of the rifle.

For bench shooting, I don't think a .311 bullet would cause any problems so long as the rifle was maintained properly.

That doesn't explain why some Russian and Domestic 7.62x39 ammo is 0.310-0.311 while other Russian ammo and domestic ammo is 0.305-0.308

Weren't some of the older AK barrels 0.308"?

To me there's only 1 way to measure the bullet diameter and that is with the use of precision instruments like a micrometer or a specialized tool. My vernier caliper has served me well for automotive work and it's very precise, down to the thousandths and you can estimate half ten-thousandths. As long as you keep the measurement methodology consistent it should not vary. If you're getting 0.305-0.306 on 1 bullet measuring 1 way, then 0.310 on the same bullet measuring another way, there's something wrong - you're probably clipping the tool onto a crimp on the neck case or something.

Wolf FMJ/JHP bullets do not exceed 0.308" at least not in the batch I tested (3 boxes of the 2003-up stuff, polymer coated cases). J45's Barnaul measurements do match what I found on the Barnaul JHP.
The Wolf SP bullets were 0.310" (pre-03, lacquer coated cases).

As for domestic bullet makers, Remington isn't the only one available... there's:
Corbon (JHP and JSP, and the JHP boasts very high muzzle velocity and energy), Winchester (USA and Super-X SP), Speer (just bullets in 0.310 for 7.62x39), PMC (Bronze), Federal Cartridge (American Eagle and Power-Shok), Maine Cartridge (uses Hornady V-Max bullets which are 0.308" though according to Hornady), and others.

Expect prices in the range of $0.40/rd up to $0.90/rd. Corbon JHP and JSP is the most expensive from what I found. When I asked them about accuracy, they said they never took groupings but they did find it was better than the Imported ammo.

Russian should be .310
that is what is was a few years ago...
and I haven't seen any differences or changes being made.

I can check and get back to you all ASAP...have the info come from the
source...

Y-

My VEPR's bore is 0.310"-0.313"

I've seen some 0.305 ammo that's 7.62x39
Wolf FMJ, JHP and Corbon 125gr JHP use 0.305" - 0.308" bullets

Barnaul, Wolf SP, Winchester USA and Super-X, Federal American Eagle  and Federal Power-Shok are all using 0.310-0.311 bullets.

Ah... I did not know that about the Corbon bullets. Have you used them before?

Corbon claims they use 0.311 bullets and want me to send back my 125gr JHP for evaluation because mine measured 0.305-0.308" and used Lapua brass cases. They asked if it had their headstamp on the casing.

Only prob with measuring 0.309 or so on a Wolf FMJ BT is that it's only 0.309 for a small portion of the bullet. Now it could very well be the poor powder charge in Wolf ammo that causes the loose groupings, but I haven't heard of anyone shooting tight groups with Remington bullets (PSP or FMJ) either (they used the ~0.308 bullets prior to recently).

American Eagle measured 0.310-0.311 at the widest (most of the exposed bullet) but did shoot consistent groups, they just weren't tight enough. Meaning, I would get the same groupings each time but they weren't as tight as I'd like (only 2" or so at 50 yd). Wolf ranged from 0.65" to 5" at 50 yd.

I've read that you want a tight fit whenever possible (bullet/bore), the Wolf BT style bullets (0.305-0.308 above crimp, 0.309-0.310 below crimp) does not give you as tight of a fit as possible even though it's "widest" size does come close to the bore size.

http://www.redpulsar.us/~coldfusion/CVN/762.gif

Well look at that, it should measure 0.311 above the crimp.

Corbon's R&D folks said they switched to 0.308 bullets starting 1/1/2004 due to possible safety concerns with using an "oversized" bullet in an AK variant.

I'm not sure what region uses 0.308 bores in an AK variant, but that's the last box of Corbon I'll ever buy.

How many here have gone through boxes of Barnaul w/o any problems whatsoever? I expect many of you have done so... Those were mainly 0.310-0.311 bullets.

I was thinking the same exact thing.

Oh well, I suppose it's a lesson learned.

Strange that CORBON would say that...
Even the Norinco 7.62x39 was .309-.311

strange they would do a .308

Could it be perhaps to eeeek out a few more FPS?

Y-