Re: Barrel Finish Length
What make is the barrel? This could have a bearing on what you do.
Are you doing the installation? If so to what extent do you have tools? Pin guages, bushings for the reamer etc....
Also what is the caliber? .22RF? .30cal. etc....?
If it's a rimfire I say cut off 1" from the muzzle when crowning it and also 1" off the breech end before threading and chambering etc...This will cover any runout from when the barrel was made.
If it's a centerfire caliber and depending on chamber length you don't really have to cut anything off the breech end. Any runout in the bore from when it was made the chamber reamer will clean up. Sometimes I will take a little off the breech end when doing installation but it depends on what I'm doing and the type of gun I'm working on etc...
Take min. of 1/2" to 1" off the muzzle.
If you have a good set of reamer bushings or pin guages in .0001" increments and it is a button rifled barrel check the bore size before and after cutting and crowning to make sure the bore didn't open up during the machining operation. If it did take a little more off etc...
On our barrels we give you an extra 1" on the blank length to cut and crown to your finish length. A 27" blank will finish at 26".
If it's a rimfire we add 1" to the breech end also. So a 26" finish length barrel you get a 28" blank on a rimfire.
Later, Frank
Bartlein Barrels