Steel has a weight per cubic inch of approximately .282 lbs. In enlarging the bore you are of course not going to enlarge the chamber & only the small end of the cone. With a 26" barrel roughly figure you are going to enlarge 22" of it. Assume a .730" bore enlarged to .740". For a not absolute, but close, figure take .735 x Pi x .010" x 22 x 2 to find the CuIn. This gives 1.04 CuIn. Multiply by .282 to find pounds then 16 to find ounces. Result is 4.7 ounces for a .010" enlargement. You would of course only reduce the wall thickness by half the enlargement, assuming centered, so would leave a .030" wall. This would drop the 7lb gun to around 6 3/4lb.

Miller/TN
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