7.62x39 Ackley Improved (30 PPC)

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Dogleg7

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I am posting my ideas for a Bolt Action rifle only, not for semi or full auto guns. Has anyone on this thread done anything concerning improving the 7.62x39 which would be kind of a 30 PPC. I have formed 7.62x39 brass down to 6PPC for one of my rifles. I have a Ruger gen 2, ranch rifle ordered that should be super light and easy to handle. If some degree of improvement would benefit performance I might order a reamer, but if someone else has already tried this and had feed or other problems then it would not be worth the doing. Please don't post back and say "just buy a bigger caliber" because I already have bigger calibers up to 458 Win.
 
troy fairweather said:
No point in that long action ruger
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Kinda my thoughts, but price drove me to build a 221fireball on the American action.

To the OP, I've always wondered the same thing, is an Ackley improved type x39 case worth it in 30 cal. Not sure you would get enough extra powder in the case to make it truly worth it. But if you buy a reamer, I may want to rent it from ya just to find out!
 
Dogleg7 said:
I am posting my ideas for a Bolt Action rifle only, not for semi or full auto guns. Has anyone on this thread done anything concerning improving the 7.62x39 which would be kind of a 30 PPC. I have formed 7.62x39 brass down to 6PPC for one of my rifles. I have a Ruger gen 2, ranch rifle ordered that should be super light and easy to handle. If some degree of improvement would benefit performance I might order a reamer, but if someone else has already tried this and had feed or other problems then it would not be worth the doing. Please don't post back and say "just buy a bigger caliber" because I already have bigger calibers up to 458 Win.
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"Improving" it won't gain much if anything. Refer to John Barsness' 4 to 1 rule. The real advantage to the "improved" rounds is greatly reduced brass stretch.
 
The American is a long action with a shorter mag and bolt stop, even in 223 and 300 blk. I have heard that the 7.62x39 stock can have the AR-15/stanag style mag well bolted in and ar style mags will work. If you improve the case a 6.5 Grendels mag may be your best bet.
 
Also wonder about loading for higher chamber pressure. 7.62x39 states 45000 psi but would assume that is for Ak type semi autos. In a new Ruger bolt action with Lapua brass, boxer primed cases could the pressure be raised (carefully, in small increments, till pressure signs) to the 50 to 55000 range. Doing that should raise velocity enough to not need improvements. Just wondering.
 
adcoch1 said:
The American is a long action with a shorter mag and bolt stop, even in 223 and 300 blk. I have heard that the 7.62x39 stock can have the AR-15/stanag style mag well bolted in and ar style mags will work. If you improve the case a 6.5 Grendels mag may be your best bet.
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Thanks for the info
 
troy fairweather said:
No point in that long action ruger
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I guess my only point is that I have about 3500 7.62x39 rounds most of which are Lapua brass, boxer primed loaded ammo. Bought that many years ago from (I could have the name wrong) J&G out of somewhere in Arizona. Salesman told me they were over run production made for either the Swedish or Finnish Olympic shooting team. I don't really know, but that is what I was told.
 
Dogleg7 said:
I guess my only point is that I have about 3500 7.62x39 rounds most of which are Lapua brass, boxer primed loaded ammo. Bought that many years ago from (I could have the name wrong) J&G out of somewhere in Arizona. Salesman told me they were over run production made for either the Swedish or Finnish Olympic shooting team. I don't really know, but that is what I was told.
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J&G is a good outfit. I bought a lot from them in the past. They get some unusual guns and ammo in occasionally and sell at reasonable prices.

Years ago they bought a bunch of 8X57 JR (rimmed .318) ammo from S&B, probably not realizing it wasn't standard 8mm Mauser variety. They blew it out, and I bought 40 boxes. I included some with drillings I had tried out and passed along, gave some to friends who shoot combo guns, and shot a bunch in mine.

That Lapua brass is a superior product. You did well. :cool::cool:
 
Dogleg7 said:
Also wonder about loading for higher chamber pressure. 7.62x39 states 45000 psi but would assume that is for Ak type semi autos. In a new Ruger bolt action with Lapua brass, boxer primed cases could the pressure be raised (carefully, in small increments, till pressure signs) to the 50 to 55000 range. Doing that should raise velocity enough to not need improvements. Just wondering.
Click to expand...
Work up slowly.

The rule for "improvements" is you get 1% more velocity for each 4% increase in powder capacity. If you added 16% capacity to the case you would only gain 4% velocity, given that pressures remained the same. I can't see where doing an AI rechamber gains enough to mess with.

Also, your standard factory ammo will lose some velocity when shot in the "improved" chamber.

I am not antagonistic toward AI chambering and have a 257 AI and 7X57 AI. I experienced improved accuracy with both and almost eliminated case trimming.
 
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Dogleg7 said:
Also wonder about loading for higher chamber pressure. 7.62x39 states 45000 psi but would assume that is for Ak type semi autos. In a new Ruger bolt action with Lapua brass, boxer primed cases could the pressure be raised (carefully, in small increments, till pressure signs) to the 50 to 55000 range. Doing that should raise velocity enough to not need improvements. Just wondering.
Click to expand...

Saami is 45,000. European CIP standard is 51,490. So ironically it is American made 7.62x39 ammo that is loaded needlessly anemic. No issue loading up to 60,000 psi in a bolt action. My favorite powder in x39 is Hodgdon CFE BLK. Shooting 125 grain 308 or .311 bullets you cannot get enough of it in the case to cause pressure issues and will produce 2550-2600 fps from a 16” barrel. I imagine a 22” barrel would be around 2700.
 
someguy2800 said:
Saami is 45,000. European CIP standard is 51,490. So ironically it is American made 7.62x39 ammo that is loaded needlessly anemic. No issue loading up to 60,000 psi in a bolt action. My favorite powder in x39 is Hodgdon CFE BLK. Shooting 125 grain 308 or .311 bullets you cannot get enough of it in the case to cause pressure issues and will produce 2550-2600 fps from a 16” barrel. I imagine a 22” barrel would be around 2700.
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Thanks for the info. This project is starting to come together.
 
luv2safari said:
Work up slowly.

The rule for "improvements" is you get 1% more velocity for each 4% increase in powder capacity. If you added 16% capacity to the case you would only gain 4% velocity, given that pressures remained the same. I can't see where doing an AI rechamber gains enough to mess with.

Also, your standard factory ammo will lose some velocity when shot in the "improved" chamber.

I am not antagonistic toward AI chambering and have a 257 AI and 7X57 AI. I experienced improved accuracy with both and almost eliminated case trimming.
Click to expand...
I have a 257 Roberts AI in a No1 B and a 223 AI that I rechambered in a NEF Handy Rifle. Still have the Clymer reamer for the 223 AI. Actually I just like the way AI cartridges look.
 
someguy2800 said:
Saami is 45,000. European CIP standard is 51,490. So ironically it is American made 7.62x39 ammo that is loaded needlessly anemic. No issue loading up to 60,000 psi in a bolt action. My favorite powder in x39 is Hodgdon CFE BLK. Shooting 125 grain 308 or .311 bullets you cannot get enough of it in the case to cause pressure issues and will produce 2550-2600 fps from a 16” barrel. I imagine a 22” barrel would be around 2700.
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Also the Ruger gen 2 ranch 7.62x39 I have ordered has a 16.1 inch barrel so your information is spot on for me. Thanks again.
 
luv2safari said:
J&G is a good outfit. I bought a lot from them in the past. They get some unusual guns and ammo in occasionally and sell at reasonable prices.

Years ago they bought a bunch of 8X57 JR (rimmed .318) ammo from S&B, probably not realizing it wasn't standard 8mm Mauser variety. They blew it out, and I bought 40 boxes. I included some with drillings I had tried out and passed along, gave some to friends who shoot combo guns, and shot a bunch in mine.

That Lapua brass is a superior product. You did well. :cool::cool:
Click to expand...
I did something like that years ago and bought a couple of boxes of Norma 7x75R. Sold 1 box at a gun show several years ago still have a box around here somewhere.
 
Any real velocity gain from the project will be from the much higher pressures possible. The AI treatment is an excellent idea to save your brass from stretching with that pronounced taper of the Russian round. It'll headspace well and be quite a bit more accurate, IMO.

Interesting Project! Please keep us informed. :cool:
 
someguy2800 said:
Are you looking to get a custom reamer and dies made?
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No, not at this time. This is just a thought project right now. Actually think that shooting some of the Lapua ammo and working up higher pressure loads will be enough to satisfy my needs. Got to my lathe and turned an accurate size 7.62x39 AI bullet clone. Still like the way they look.
 

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adcoch1 said:
Kinda my thoughts, but price drove me to build a 221fireball on the American action.

To the OP, I've always wondered the same thing, is an Ackley improved type x39 case worth it in 30 cal. Not sure you would get enough extra powder in the case to make it truly worth it. But if you buy a reamer, I may want to rent it from ya just to find out!
Click to expand...
Can you elaborate on the build? I have some Fireball brass I’d like to put to use.
 
30 GPC is another great option. I do know the bolt head size it different. But maybe there will soon be aftermarket bolts/bolt faces to get any head size you need.
 
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