Keyholing rifle rounds, what gives?

[Lennyjoe]

Noticed today that my 22-250 had a few rounds keyhole.

Standard load is Varget and 50gr V-max doing 3900fps. 95% of them shoot fine but out of 30 rounds I had 2 keyhole

Also, loaded some 50gr Sierra SP and when I got near max with Varget (36gr) all 5 rounds keyholed. Loads from 33.5 and up fired fine but when I got to the 36gr loads they all went haywire. I used the printed COL for this load as well.

Is it something I'm doing or is my barrel suspect?

 

[TexasRifleman]

What's the barrel twist rate?

 

[Jim Watson]

Bullets are fragile for the velocity produced. They are getting deformed from barrel heat and centrifugal force. Load a little hotter and they will break up entirely.

 

[Lennyjoe]

You could be right Jim. The barrel was getting pretty hot.

As for twist rate, 1-12.

 

[NMshooter]

3900!

Who needs a Swift...

 

[redneck2]

I had a friend that had a Swift. He'd load them high, and they'd get maybe 50 yards out and you'd see a little grey "poof". I think you're close.

 

[jerkface11]

Add some more powder exploding bullets are cool.