allowable bore sizing on 50 cal

[charger 1]

I know we say that with boolits the final sizing should be done in bore. This must however get to a point of no return for size increase. In short I know that if I stick a good 512 boolit through my 510 bore all is well. I know not to stick 520 through with a warm load. I guess what I'm looking for is an opinion as to where it no longer does good to increase size but rather is of detriment

[45 2.1]

Chamber neck diameter - 2 x (avg. case neck thickness) -0.0015" = boolit sized to diameter for a maximum if you want it to chamber in a pinch.

[charger 1]

Chamber neck diameter - 2 x (avg. case neck thickness) -0.0015" = boolit sized to diameter for a maximum if you want it to chamber in a pinch.

I'll rephrase. If that makes for a .005" interference bore to boolit then that would be OK?

[45 2.1]

I'll rephrase. If that makes for a .005" interference bore to boolit then that would be OK?

I'll rephrase also. I would suggest that you fit the cast boolit as posted, then use a starting load and work the load up to a reasonable level and find out for yourself. No one here knows what your going to do, so your going to get an answer like this.

[charger 1]

I'll rephrase also. I would suggest that you fit the cast boolit as posted, then use a starting load and work the load up to a reasonable level and find out for yourself. No one here knows what your going to do, so your going to get an answer like this.

Well I called PTG today and had them knock the reamer down to where as I have .0015-.002 max between loaded cartridge and chamber neck dimensions

[leftiye]

Charger,
Was that with cast of the size that you plan to use, or with standard diameter Jword bullets (reamer dimensions)?

Sorry for the run around you've been getting. As you haven't decided what size the reamer was going to be, calculating from chamber dimensions could be a little bit hard. I never size more than a couple of thou bigger than groove diameter FWIW.

My feel here is that you should design your reamer for "ideal" dimensions. That is- since you can have whatever you want, get what is the best that you can figger out. As for chamber neck dimensions that would be groove diameter and one or two thousandths, plus 2X the brass' (YOUR brass') neck thickness, plus at least .002" fer clearance.

And then you might want to go a thou. or two more for when your throat erodes, or your groove diameter gets a little bigger. Neck clearance however can be opened up later with a chucking reamer to whatever you need, so I'd stay with the .002" clearance.

[charger 1]

Thats pretty much where I'm headed. Thanks for YOUR input