Reloading die question.

[Changeling]

I'm not a machinist !

When someone says they are getting a custom die made by their gunsmith with the reamer that was used to chamber the rifle it doesn't make sense to me.
The die chamber would be the same size as the rifle chamber (two tight) wouldn't it be ?

Is it just as good with several dummy cases sent to the gunsmith when people don't have a reamer, how can he machine to the correct specs without a reamer?

I'm confused on this subject, especially since a clambering reamer is also offered by the reamer maker. Straighten me out, please.

 

[Gappmast]

I think they are talking about making a custom seating die. You are correct you can not use the same reamer that chambered the barrel to make a sizing die. But it can be used to make a seating die.

 

[coldboreshot]

I believe the chamber reamer can be used to cut the sizing die. It would only effect the shoulder setback and not the body as some prefer. That way, you don't have to (cam-over) you press to achieve the shoulder bump. The neck can also be cut and honed to a specific size for neck tension according to particular brass and owner's specs. Forster already offers a version of this die setup but the difference lies in sizing die cut exact to your chamber.

 

[DaveTooley]

I believe the chamber reamer can be used to cut the sizing die. It would only effect the shoulder setback and not the body as some prefer. That way, you don't have to (cam-over) you press to achieve the shoulder bump. The neck can also be cut and honed to a specific size for neck tension according to particular brass and owner's specs. Forster already offers a version of this die setup but the difference lies in sizing die cut exact to your chamber.

First you have to "cam over" to reach the stop on the press. Also the neck will be the same diameter as the chamber. It's impossible to make it smaller without altering the reamer. With the finish reamer you can make a neck sizing die that uses a bushing. You do not want to bump shoulders in a neck sizing die. Most of the time the body will expand slightly and cases will get tighter in the chamber.

 

[ridgeway]

The chamber reamer is commonly used to make seater dies, mainly inline. The reamer maker will gladly make a custom sizing die reamer so you can make whatever type of sizer you desire.

 

[Changeling]

Thanks to all for there input, especially Dave Tooley.

 

[ireload2]

When a reamer is ground they often make a slightly smaller roughing reamer that is the right dimensions for a sizing die and the finishing reamer is the right size for a seating die.