I have a Mini Mauser bolt action rifle in 7.62x39. Bought it to eventually make it a project rifle but it shoots cheap steel case Wolf ammo into 2" groups with a 2-7 scope on it. I thought that showed promise.
I loaded up some 125 grain Sierra's and 28 grains of TAC in Remington brass and WW primers but the load seems very soft (mild) and 5" groups.
I was wondering if there is any magic that the 7.62x39 usually responds to before I really start working up a load from scratch.
So far I haven't found TAC to be the most accurate powder in anything yet however I don't have a lot of experience with it.
Thanks in advance.

I bought a Mini Mauser X years back and had similar issues to yours. It would shoot Euro surplus ammo OK but my initial reloads - not so much. The issue I discovered was the bore dia. Do check yours, mine measured out at a full .311". Once I found that the Sierra 125g SP measured a full .311' where as some manufactures split the difference and run their 125's about .3095" or less, everything changed. Lee offers their dies with both a .308" & .311" expander which was a big help.

Long story short, loaded up the Sierras with AA680, 4227 and achieved markedly improved accuracy.

I also found the bedding in the lug area very poor, a little Brownell's Accu-Glass solved that.

Hope this helps.

Don't have my book in front of me but H-322 has worked well for my son's rifle.

I owned one of the Zastava Mini Mark X's in 7.62x39 and despite my best and most sincere efforts couldn't get any bullet of any weight or diameter, factory or handloaded, to shoot inside of 4". After failing with every trick I've learned in 50 years of shooting I gave up and sent it on to another more optimistic owner.

By the way, I have a custom .221 Fireball on the MMX action and it is as accurate a rifle as I've ever owned.

Update!
Well I've tried everything I can with 125 grain .308 diameter bullets, 2 different powders, 8 different charge weights of powder, 3 different primers, 2 scopes, crimping and not crimping and I free floated the barrel. Groups are 4" +.

I will now try this all over again with .311 .310 diameter bullets.

Sounds like a good time to buy a bullet mold and start casting

How fast can you push cast bullets?
I don't know the first thing about it.

If you use a gas checked mould, cast from pure linotype, use the correct lube, and size the projectiles to your bore, 2400-2500 fps is very doable with cast.

That will be fine for a 125 or 150 grain 7.62x39,
it ain't no 30/30!

I "may" give cast a try after I try cup and core .310,.311's.
Thanks guys.

Have a look at our Reloading Pages

There is some data we developed in a custom rifle we built for this cartridge.

Thanks Saeed.
I'm assuming you guys were shooting .308 diameter bullets.

quote:

Originally posted by Snellstrom:
Thanks Saeed.
I'm assuming you guys were shooting .308 diameter bullets.

Yes, as our barrel was .308.