Just purchased a bunch of Tula, Herters and Silver Bear ammo and ALL have bi-metal bullets that a magnet will detect.  Now these bi-metal bullets appear to have lead core's but the jackets are steel with a flash coating of copper.   IMHO not enough of a copper coating to protect the bore.   The steel causing premature bore wear.   So it looks like I will shoot them up in my beater I.O. AK-47 and save my reloaded (hoarded brass cases) copper jacketed .310 dia. lead core Hornady FMJ bullets for my Yugo 70AB2 underfolder  equipped with an ultimak and a TRS-25 red dot sight.   Shoots so good I wont shoot the Russian crap in it.    YMMV

The soft steel jacket is not going to wear out a chrome liner hammer forged barrel in your lifetime. AK's have been using this type of ammo for 60+ years now. With proper maint. the bore should last to the 30,000 rds. mark or beyond.  Even non-chrome bores last well into the 15-20,000 rds. range.  This is of no concern unless you plan and dumping mag after mag in full auto.

You bought a bunch of Russian "crap" ammo before educating yourself about it, and now you are complaining about it?

The copper (gilding metal actually) coating is not a "flash" coating. It is cladding. Physically bonded to the steel in a process done before the projectile jacket is even formed. While thin, it provides protection against corrosion and a barrier between the bore and the mild steel jacket. Much ado about nothing. You will do more damage to your bore by doing mag dumps and improper cleaning than shooting bi-metal jacketed ammunition. Most of us are not going to shoot enough of any sort of ammunition to wear a barrel out, regardless of what ammunition we are using.

And seriously, it's an AK. It's not like they have match grade barrels or anything... You will save enough by shooting bi-metal that you could buy two new barrels if you ever wore one out...

Your Yugo shoots so well, due to the Ultimak, red dot and handloads (maybe) not because it has a better than average barrel...

1DD

This.
You wont wear out the barrel, you will run out of ammo or money to buy the ammo to wear a commie AK barrel out.
Take care of it and it will outlive your grandchildren.

Okay...so it's good to go....thanks.    Now regarding bore diameter.....the barrels that are being manufactured here in the U.S.A. for installation on AK-47  remanufactured rifles ....are they .308 bore diameter or .310 bore diameter?    As this also relates to the steel jacketed bullet wear,  I realize its only .002 (.310 vs. .308)  but always was curious w.o first slugging my bore on my I.O. rifle.   When I contacted I.O. they e-mailed me that their barrels were .308 dia.

I guess none of you read the study that LuckyGunner did on bimetal jacketed ammo.

It'll ruin your barrel in less than half the time of regular copper jacketed ammo.

yes but you can buy a new barrel with the money you saved...so it's tit for tat or just don't buy the ammo more for me.

Yeah, impressive test they did. The test was done with Bushy ARs, but I don't see how that would be any different than an AK barrel. The AR they used was a Bushmasterl BCWA3F MOE which has a chrome-lined bore. But please feel free to school me on how a chrome-line barrel on an AKM is different from an AR.....

http://www.luckygunner.com/labs/brass-vs-steel-cased-ammo/

Tula ended up being the most effective killer of the Bushy barrels. Great comparison pics, check it out if you haven't already.

One thing I'd like to do and should do with my AKs, as I only have 3, is to do a chronological bullet drop test, as I lack any other equipment to do a test. The problem, I don't shoot nearly as much as I would like to. I think many of us are in the same boat there. Additionally, I shoot a variety of ammo out of my AKs, usually it's based on whatever I can get on the cheap. Still would be interesting to conduct such a test.

Kinda boils down to how much you will shoot that barrel, and what you consider acceptable accuracy.  I've got a bushy CL barrel with 16K+ wolf, tula, etc, through it, and i can still hit a sheet of printer  paper at 200 yards.

The test Lucky Gunner did is not a scientific or valid study. It only shows what happens when you rapidly fire certain .223 cartridges through certain AR-15s. To be honest with you, it was a torture test that subjected the rifles to wear beyond what just a bimetal jacket will cause. Much of the damage done can be attributed to the guns being abused and run hot. If this is how you treat your weapons, then that is what you can expect to happen. Perhaps you can expect similar results in different calibers and weapons, but there are just too many variables to make this one test the be-all-end-all definitive answer to the bi-metal jacket issue.

Bi-metal jackets are nothing new. They have been around and in widespread use since well before WWII. If they were that bad for a barrel, no one would use them...

The US adopted bi-metal jackets during WWII due to raw material shortages, calling them "alternate". Testing showed only a slight increase in barrel wear compared to the standard gilding metal jacket.

There is no doubt that bi-metal jackets cause more wear than gilding metal jackets, but their effects are greatly exaggerated...

There are other variables to consider besides the projectile material. The powder type, the powder charge volume, the rate of fire, the velocity of the cartridge, how hot the gun gets and for how long. you can't pin barrel wear on the jacket material alone. Plenty of barrels have been shot out with ammunition using gilding metal jacketed projectiles...

1DD

5.56 is a much higher pressure round than the 7.62x39, this makes a big difference in bore life. Regardless of all the variables it is very difficult, but not impossible, to wear out any AK barrel.

To say nothing of all the old warhorse Mausers shooting a diet of steel without benefit of chrome lining.  Not an issue at all.  Soft steel jacket over lead = no problem.

So, OP, what is you pet handload?

My Yugo 59/66 (non-CL barrel) has been fed a steady diet of bi-metallic bullets (I haven't counted but several cases at least) and the rifling is still crisp and strong. I am not worried that I will ever "shoot-out" this barrel. Like others have said; 1) avoid needless mag dumps 2) properly clean and care for the barrel and your great-grandchildren will still be enjoying your 7.62x39 chambered gun.

I'm going to start reloading for 7.62x39 anyway. I try to minimise the amount of money I give to our enemies. With cheap bullets I may be able to reload it cheaper than Tula Walmart prices or break even.

Also, I'm in my early 30's and I'd like to have far more than 30K rounds through my AK before I'm 50.

...if you shoot 10k rounds in one day.