New Model 12 LRPV ammunition advice needed.

[darkker]

MV = Muzzle velocity

RPM = MV * 720 /Twist

Remember that bullet weight isn't important for twist, it's a generalized rule for length. The 75gr Amax is notably longer than the 77gr SMK. I called all the majors some years ago and inquired about RPM limits for the .224 bullets. Sierra and Nosler match bullets have the thickest jackets, and can withstand roughly 320,000 RPM. Hornady and the rest(didn't talk to Berger) are more like 290,000 RPM, but your particular barrel smoothness will play a large role in the ultimate number.

You may find that the shorter, thus lighter weight and thinner jacketed varmint bullets, will come apart if you fire them quickly.

[Scott Evans]

MV =

You may find that the shorter, thus lighter weight and thinner jacketed varmint bullets, will come apart if you fire them quickly.

Depends. Some are made for high velocity/high spin rate, some are not. Sierra will tell you if they are for std vel or high.

I just loaded some 224 40 Blitzkings to 336K RPM worked fine. I've shot 6mm 70 Blitzkings at 342K and they worked great. 6mm 70TNT had to be kept below ~290K and didn't tolerate a dirty barrel. 204 39g BK's were fragile for me. It just depends. The high spin rate makes for some serious splat factor on PD's.

[darkker]

Yes, it always depends.
The original TNT's have a spec'd RPM limit of @ 240,000 rpm, but as I said, barrel dependant.
The SMK's and Blitz's have the thickest jackets, not the others.
If you want I can link my OP from another forum with the particulars I got from the MFGRs.

[Scott Evans]

Yes, it always depends.
The original TNT's have a spec'd RPM limit of @ 240,000 rpm, but as I said, barrel dependant.
The SMK's and Blitz's have the thickest jackets, not the others.
If you want I can link my OP from another forum with the particulars I got from the MFGRs.

That'd be cool info to see.