Old dog needs help learning new trick

[VaRandy]

My rounds will not be fast enough to generate heat. When I pull the trigger, something normally dies!
Obviously I don't shoot Prairie Dogs!

 

[VaRandy]

I am leaning 6 mm Ackley. Does anybody make quality brass for the 6 mm?
If I build this it will be with a 8 twist 29 inch barrel and I need to reach 105's at 3300. My research shows that most on the net have 10 to 14 twist barrels, very high speed bullets that are 70-90.

Does anyone have recent experience with long 8 twist barrels. Loads also mostly show slower twist barrels and lighter bullets. Specifically, what powder will hit the target 3000 fps with the 105's. Mentioned have been VV160, RE22, RE26, and many others.

What are the chances the 6mm Ackley can shoot as small groups as a .243 Ackley. The purpose of this specific build is groundhogs at 1200 or more yards.





thanx to all that replied.

 

[spclark]

Nosler, Winchester & Remington all make brass for it.

Any of those can be hard to locate but according to its essay on Wikipedia as it's based on the 7x57 Mauser you ought to be able to use that, or even 308 Winchester?

I've used Lapua's Palma 308 Win very successfully both for making 6XC as well as a 'neckless' (almost!) 7mm wildcat called 284INCH brass. Its small rifle primer pocket case heads seem to hold up longer than the LR variety so were I in your position I'd start there!

 

[VaRandy]

sent you a PM !

When you think on it, the 284 case is just about the size of a .30/06.

The 6mm/06 and 6mm/284 have a number of wins at 1,000 yards. One step down is a 6 Ackely (6/7x57 improved). I had a 6/284 (actually, a 6 on a7.5x55 Swiss case) with the reamer held back .200. It had exactly the capacity of a 6 Ackley, which I also have. 106 Clinch rivers at 3,500 shot quite nice. The guys shooting 107 Sierras with a 6/.30-06 (old days) could get 3,600 with maybe a "plus."

I can make an argument for it to use at 1,000 yards. Not much of one, but an argument. Even Shehane backed down in case size, I believe his last 6mm was based on the 6.5x47 Lapua case.

For 600 yards, it would be a bit much. One thing to think about: with the smaller 6mms, you can shoot free recoil, without a muzzle brake. Harder to shoot free recoil without a brake with anything much bigger, though I did do this with my 6 Ackley.

FWIW, and that's not much.

Edit; BTW, that 3,500 was with Rel-22; I had a bit better accuracy with 4831, around 3,300. And the speed dropped before the throat washed out.
Last edited by C

copied and pasted out of archives..... not at all uncommon for a 6-284 with 105`s to go mid 3000`s ft/sec.
bill

 

[IdahoSharpshooter]

Does anyone posting these super fast 6mms have pressure data...?
From what I have read the last fifty years or so, there are two methods to get high MV.
Bigger case at moderate pressure, or a smaller capacity one at high pressure.