View Full Version : What caliber is this blank for?

July 17, 2010, 03:11 PM
I have an 18 inch 1" dia barrel blank that I bought at an auction. I slugged it and I get a bore measurement of .443 and the rifleing is 1 in 16". It is marked "45 cal" any ideas what I should chamber it for or what it was designed for? I thought I could use it for a 450 bushmaster but now I'm not sure. :confused:

July 17, 2010, 03:46 PM
You said the bore diameter. Did you actually mean the bore diameter or did you mean the groove diameter? If that is the actual bore diameter, it is correct for .45 caliber, which has .451" groove diameter. That is what a .443 bore comes up to with .004" deep rifling all around (which is standard).

James K
July 17, 2010, 08:37 PM
If it is exactly 18", you don't have a lot of leeway if you plan to use it on a rifle since if you go under 18" you run into legal problems. (You can get around that with something like a welded on muzzle break, but be careful.)


Bill DeShivs
July 17, 2010, 09:17 PM
Rifle- 16"
Shotgun- 18"

James K
July 19, 2010, 01:23 PM
Ooops! I really do know better, Bill.:o


July 19, 2010, 04:10 PM
Thanks guys,
My plans are to build a single shot bolt action pistol with this blank (similar to an XP100 remington) . I built one several years ago in 357 max and have been very happy with it. It has a 17" shaw barrel and is 26 1/2" overall. It will shoot 1" groups at 100 yards with 180gr psp handloads. On this one I am going to try the 450 bushmaster if I can find a chamber reamer. I'm also building 2 more in 44 mag for my son and a friend.

July 25, 2010, 12:46 AM
Adds a whole new meaning to the term "hand cannon".