casting for 22-250

[compass will]

Well my first mold for the 22-250 is on it's way.
I want to lube (and seat gas checks) with my 4500 , would you recommend a .224" or .225" sizing die?

for loading dies I have Lee Collet sizing die, the cases have been fired at jacketed load levels once so far. I think the .225 would fit without problems.

No I have not done a casting of the chamber. It's in a H&R 22-250 24", flutted, bull barrel if that matters.

CW

[leftiye]

Do a chamber cast. Measure it 1/2 hour after making it (it will be under or over at all other times). Make yer boolit .001 or .002" over groove diameter or make it freebore size, whichever is largest.

[Larry Gibson]

Agree with leftiye. I'd also suggest micing the inside of a fired neck. If your bullets "as cast" diameter is smaller than that then I'd only seat the GC and size to as close to that as I could. Of course as leftiye also mentions if there is any freebore (long throat) then the bullet must fit into that if you are going to seat the bullet so the driving band touches the lands. Adjust the collet die to give you .002" neck tension on the cast bullet.

Larry Gibson