Measuring Bore Diameter In Fixed Breech Guns
07-15-2012 | 09:20 PM
#1
Thread Starter
Boone & Crockett
Joined: Apr 2007
Posts: 10,918
Likes: 1
From: River Ridge, LA (Suburb of New Orleans)
Measuring Bore Diameter In Fixed Breech Guns
If you have a micrometer or calipers there's an easy way to determine the precise diameter of the bore of a muzzleloader that has a fixed breech.
First, make sure the bore is very clean and lightly oiled. Slide a brass rod that's about six inches long and slightly under bore diameter into the bore. If a brass rod isn't handy, a steel rod may be used, but should be wrapped with tape around each end to protect the bore. Then oil a soft lead ball that's slightly larger than the bore (or a fattned bore size ball) and tap it into the bore five or six inches deep. Now wipe the bore between the ball and the muzzle with an oil patch, then hold the barrel (or gun) at it's mid-point and rock it up and down in a see-saw fashion so the rod slides back and forth within the bore and taps the ball back out. Guide it to fall on a soft surface. It will be perfectly engraved with the barrel's lands and grooves for measuring.
First, make sure the bore is very clean and lightly oiled. Slide a brass rod that's about six inches long and slightly under bore diameter into the bore. If a brass rod isn't handy, a steel rod may be used, but should be wrapped with tape around each end to protect the bore. Then oil a soft lead ball that's slightly larger than the bore (or a fattned bore size ball) and tap it into the bore five or six inches deep. Now wipe the bore between the ball and the muzzle with an oil patch, then hold the barrel (or gun) at it's mid-point and rock it up and down in a see-saw fashion so the rod slides back and forth within the bore and taps the ball back out. Guide it to fall on a soft surface. It will be perfectly engraved with the barrel's lands and grooves for measuring.
Last edited by Semisane; 07-17-2012 at 07:51 PM.
