Reamer question

[haisardao]

For the Gunsmiths here, what would be the difference between chambers if you cut them with a reamer with a longer free bore than SAAMI or cutting the chamber with a SAAMI reamer and adding free bore afterwards with say an uni throater. Thanks

 

[MagnumManiac]

For the Gunsmiths here, what would be the difference between chambers if you cut them with a reamer with a longer free bore than SAAMI or cutting the chamber with a SAAMI reamer and adding free bore afterwards with say an uni throater. Thanks

Chamber dimension, if the same on both/either reamer, are the same, then nothing changes but the throat length.
I run A191 reamers in my comp 300WM's, this changes 2 things, shoulder position over SAAMI and throat length over SAAMI.
Although not a true issue until after the first firing, .008" makes quite a difference to the brass even though the belt is still the governing headspace on the first firing, only difference is that the shoulder isn't blowing forward .020".

Cheers.

 

[Tiny Tim]

Tagging in

 

[biednick]

Assuming all the dimensions are the same except the length of the throat and you cut the throats to match there is no difference. Starting with a shorter throat and lengthening it gives you more options down the line. You can always make the throat longer than the base reamer, but you can't go shorter.

 

[haisardao]

Thanks for the thoughtful answers