Over-spinning bullet…until they come apart

My 6.5 creed boolits b like
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Click to activate I guess 😂
 
This thread has devolved to the ridiculous. How many angels can dance on the head of a pin. It is NOT THAT FRIGGIN COMPLiCATED. A 1 in 10 or 12 twist is designed for light, short bullets that tend to work good on stuff under 400 yards. If you punch them out of a 1 in 7 twist many, but not all, will vaporize. Pick the right bullet for the speed and twist, and distance you want to shoot, simple as all get out.
 
..I had a friend that had a benchrest quality rifle built in .243AI fast twist, I remember him scratching his head at a match trying to figure out why he couldn't hit the 100 yard groundhog target...as the range master I went over to see what the problem was, he was shooting an 87 grain bullet that made it about 10 yards from the barrel before completely vaporizing itself, one of the most amazing things I ever saw at a match. After firing if you watched closely, you'd see what looked like a flash of oil on water, beautiful colors, I guess the metals going from solid to liquid to plasma... they just couldn't handle the fast twist barrel and velocity, never saw it before or since...crazy part was all the shooters and spectators just had to come and watch..actually paused the match..
 
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This thread has devolved to the ridiculous. How many angels can dance on the head of a pin. It is NOT THAT FRIGGIN COMPLiCATED. A 1 in 10 or 12 twist is designed for light, short bullets that tend to work good on stuff under 400 yards. If you punch them out of a 1 in 7 twist many, but not all, will vaporize. Pick the right bullet for the speed and twist, and distance you want to shoot, simple as all get out.
And vice versa...pick the right twist rate for the bullet weight/length and distance you want to shoot.
 
And yes, MVx720/Twist Rate=RPM is the simplest formula. Most cup and core bullets are good up to around 320,000 RPM with a few exceptions. There was a time after introduction when the 147gr .264 ELD-Ms were blowing up well below this number. Hornady seems to have fixed that issue. I built a 22 Creed with a 1/7 twist barrel specifically for shooting the then-new 95gr Sierra MatchKing. It shot that bullet extremely well but would "poof" lighter bullets at higher velocities. The older/rougher and more heat checked the throat became, the more frequently it would do it. Toward the end of the barrel life, I ended up shooting CEB MTAC monolithics which also performed well. I ended up changing it to a 6 Dasher as I had other options for shooting heavy 22 bullets. The .224" Hornady SPSX bullets are another one that comes to mind for being very thin skinned and explosive when spun too fast.
 
Update:

I wrote Sierra Bullets to see what their take is. Here's their response:
Twist rate is only 1 factor in play here, Velocity, Pressure and barrel wear play just as big a role. Typically a 1-8 will shoot those bullets well till the throat starts to wear and fire crack. At that point you will start to have jacket separation issues. This will start to occur somewhere around 500 round depending on how hard you push you loads.

So...they didn't give me any specific RPM or velocity.
 
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