doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com making heavy barrels lighter

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.

What was the original weight ?

Do you mean prior to sleeving? Current weight is 7 lbs.

One way is to remove the ribs, install two small bridges between the barrels following the Alex Martin Ribless model.

According to one of the Brown family gunmakers, who built the gun for Alex Martin, leaving out the ribs removed a 1/4 pound off the front where it matters most. It also did away with the hidden rust trap between the barrels.

If you absolutely must have a rib you can fit a carbon fiber snap-in rib as a top rib, weighing some 30 grams.

It is a thought for those who are not addicted to ribs.

2-Piper, Many thanks for the math. Good to know. All the thoughtful comments have slowed me down a bit. Good to think things through.

2-piper I love math and that explains it so well. I need to get my barrels out and figure out if we took .010 out of the wall or I just had him open up the bore .010 which would be half the metal removed. My need was to remove pits not lighten the barrels. The barrels were 30" long so I bet it was just open up the bores.

Too many projects to keep them all straight. I have noted several guns felt slightly lighter after having the bore cleaned up but .005 takes care of most pits I have had removed. Or to put i t another way if the pits are much past .005 I try not to buy the gun in the first place.

After over boring the barrels you might find it desirable to hollow out the buttstock some to balance it. If so, another couple ounces might be eliminated.

Folks I had a senior moment, sorry about that. I was figuring for taking .010 from the diameter so the .735 (Midpoint of metal removed) should have been multiplied by .005" rather than .010". Thus actual weight removed would be only half what I said or about 2.35oz. My figures were for removing .010 per side or .020 " from the bore diameter. These "New" figures are very close to what you remember Jon.
Thus with just the bore enlargement of .010" you are looking at closer to 1/8 lb rather than � lb. While I am not in grouse country I did on one occasion do some very good shooting on quail & some woodcock with a 12ga J P Clabrough with 28" damascus barrels @ a weight of 6 lb 14 oz.Balance of the gun & fit just seemed to be perfect for me & it didn't feel that heavy. I was however a bit more physically fit at the time than at present.

I thought I always have regarding sleeved barrels being "heavier" is: are they really? I realize it all depends on the barrel profile but it seems to me that it is just as likely, if not more so, that such new barrels are closer to the gun's original weight distribution.
Any thoughts?
Jeremy

One problem with overboring .010: You just took your gun out of proof.

I'd echo the suggestion that in the long run, the best option might be to trade into another gun that's lighter from the start.