Fast twist 22-250 question?

[308cal]

If I have a fast twist 22-250 that is throated for 75 gr bullets, will I burn the barrel out any quicker running shorter 55-65 gr bullets? Just wondering if the blowby of flames and hot gasses would quicken burning out the throat?

 

[woods]

If I have a fast twist 22-250 that is throated for 75 gr bullets, will I burn the barrel out any quicker running shorter 55-65 gr bullets? Just wondering if the blowby of flames and hot gasses would quicken burning out the throat?

I guess I'll be finding out although I have never fired enough loads out of any one barrel to burn it out. I have a new rebarrel from a 260 Rem rifle to a 22-250 with a 1 in 7 twist 3 groove Pac-Nor. The bullet I am wanting to shoot is the 75 gr Scirrocco II.

So far I have fired 37 shots with new Lapua brass to come up with a load of 37 gr RL17 (love that powder!) and am loading those 37 resized cases (Arbor press and Wilson Neck Sizer with .429 bushing) with that load of 37 gr RL17 seated at .050" off, OAL of 2.600". That .050" off gave the lowest ES & SD and not the best accuracy, still breaking in the barrel and accuracy may improve with the resized rather than new cases.

A couple of things:

The Wilson Neck Sizer and the Lapua brass yielded the lowest runout I have ever seen as measured close to the case mouth on the brass (haven't loaded bullets to measure yet)

And to answer your question, or a least ONE possible answer to your question may be found in this chart

which seems to indicate that one factor of barrel life is how fast your powder is, the slower the less barrel life. Essentially I am settling for around 1500 rounds cause RL17 is very close to 4350 in burn rate. IMO if you load for lighter bullets then a faster powder would be indicated which means a longer barrel life.

 

[lancetkenyon]

.429 bushing for a .22-250? Maybe .249?

 

[ShtrRdy]

woods -- where did you find that table?

 

[woods]

.429 bushing for a .22-250? Maybe .249?

Yeah, you got me, .249. I had the neck chambered at .255

I've had that table so long I don't recall where it came from