Thread: Can I cut a sizing die with a finish chamber reamer ?

Unless you are running at fairly high pressures (unlikely) then all you need to think about is the getting the neck sized (a bit) so it'll hold a projectile - and you'll get sick of shooting it before your brass needs a full length size . . . .

I read an interesting post on a US website (maybe accuratereloading.com) where the poster machined a piece of steel using the chambering reamer and then had the machined steel piece heat treated to shrink it so that it could be used for resizing cases. I had a look on fabulous google and noticed this https://www.productionmachining.com/...heat-treatment
which goes into a bit of detail about shrinkage/expansion of steel during heat treating. I think a heat treat engineer would be able to recommend the right kind of steel and heat treat to make a resizing die using the chambering reamer.

make your die with the finish reamer then have it hard chromed. It can be deposited with great accuracy in thickness.

Could do all your roughing cuts to get the die close to size and then get the part nice and hot, and run the reamer. Maybe it will contract enough at room temperature to give the correct clearance.
Probably better to have some sort of layer put on it like other have suggested. Hard chrome would likely make for an indestructible die.

Originally Posted by SixtyTen

Could do all your roughing cuts to get the die close to size and then get the part nice and hot, and run the reamer. Maybe it will contract enough at room temperature to give the correct clearance.
Probably better to have some sort of layer put on it like other have suggested. Hard chrome would likely make for an indestructible die.

especially if you used SS as it expands a lot when warm. take it up to 100 degrees and it will have grown 0.05mm