22-243 with 95 grain Sierras

[padom]

I have plenty of twist rate. I believe it's 1:6. I think may set this back to 22x47

Yea....I wouldn't be using a 6 twist just. Especially at 22x47L velocities....just going from a 7.5 twist down to a 6 twist in my 22GT means going from 282,000rpm to 354,000rpm with 95smk.....thats way too fast. Rule of thumb is keep them under 320,000rpm.. I find 280-300k is the sweet spot

 

[padom]

At what pressure will it run a lot faster? Peterson brass ran loads in their universal receiver to test pressure.
The 22 CM w/95 SMK @3150 fps was 70,493 psi. SAAMI Max pressure for the parent cases (6 & 6.5 CM) is 62,000 psi.

A lot of missing info here.. what bore diameter. 218 or 219? What's the freebore? What powder? All of that changes pressure.

But from my testing...100-150fps faster....3050 seems to be the sweet spot

 

[Shurefire]

Yea....I wouldn't be using a 6 twist just. Especially at 22x47L velocities....just going from a 7.5 twist down to a 6 twist in my 22GT means going from 282,000rpm to 354,000rpm with 95smk.....thats way too fast. Rule of thumb is keep them under 320,000rpm.. I find 280-300k is the sweet spot

Are your 90’s and 88’s still stabilizing in the 7.5 twist?

 

[padom]

Also, for reference...Copper Creek 22cm 95smk ammunition 20rd boxes for $56.99 using Peterson brass and states 3160fps out of a 24" barrel on the box.....

22 Creedmoor 95gr Sierra Matchking – Copper Creek Cartridge Co.

coppercreekcartridgeco.com

 

[padom]

Are your 90’s and 88’s still stabilizing in the 7.5 twist?

Absolutely. Stupid accurate out to 1000yd.. I shoot 90smk and Berger 85.5's in my 22GT


34.5gr N550
3139
SD2

0.1's @ 100yd and 0.3moa 5 shot groups at 800yd my last outing

 

[Shurefire]

Absolutely. Stupid accurate out to 1000yd.. I shoot 90smk and Berger 85.5's in my 22GT


34.5gr N550
3139
SD2

0.1's @ 100yd and 0.3moa 5 shot groups at 800yd my last outing

Ive found similar accuracy in my 22cm with the 90’s and v165, but if i go above 2900fps I have reliability issues, so Ill definitely be trying the 7.5 twist on the next barrel. Crazy to hear the velocity your getting with a smaller case in the GT.