The barrel weight question is something that people often quote as a problem with sleeving . But on a 100 plus year old gun that now has a bore size .015" above original proof size and wall thickness of less than .020" you should ask yourselves what did the barrels weigh when the gun left the factory in the days or roll turn over 2&1/2" black powder . Not modern 2&3/4" nitro loads that the gun will be expected to use now . Ask also has the stock worn or been renovated ,shortened ,is it thin/worn in the hand and has this affected the balance ?