Pistolero
Well-Known Member
I would like to make a .30 cal M-type expander, but not sure of dimensions. If someone could
give me the initial diameter, then the diameter of the step, and the length of the initial expander
portion, I would appreciate it. Please measure with a micrometer, not a caliper.
I assume that the expander leaves a couple of thousandths of interference fit. Since I use .311
to .310 for my .30 cals, then I guess something like .308 or .309.....but there will be some
springback, too, I think. I think the step is actually larger than the bullet, so maybe that
needs to be .313 or .314? I could try all this, but copying one that works well should be
quicker at getting there.
Thanks.
Bill
give me the initial diameter, then the diameter of the step, and the length of the initial expander
portion, I would appreciate it. Please measure with a micrometer, not a caliper.
I assume that the expander leaves a couple of thousandths of interference fit. Since I use .311
to .310 for my .30 cals, then I guess something like .308 or .309.....but there will be some
springback, too, I think. I think the step is actually larger than the bullet, so maybe that
needs to be .313 or .314? I could try all this, but copying one that works well should be
quicker at getting there.
Thanks.
Bill