and shake before using. Use the mixture freely for all barrel reaming operations.
AfteT the first reaming cut in muzzle, again measure the bore. From one to three thousandths will usually make a big difference. Now polish off the taper of choke as before described, so that there will be no sharp angle between the straight section and beginning of choke. Test the gun by patterning. A second or even a third reamer cut may be necessary, but usually one cut, with subsequent polishing, is sufficient.
Chamber reaming should never be attempted by the amateur, nor by most gunsmiths unless they are experienced barrel makers. If not satisfied that your gun is chambered correctly, take a sulphur cast of chamber and cone, and measure it up. In bore polishing it is important that the cone is not altered, and the polishing should end at or very near the front end of cone.
The following are average diameters of standard shotgun bores, although makers will vary slightly from these. This average measurement should not be enlarged at the point just ahead of cone even though balance of bore may be enlarged somewhat in polishing:
4 gauge 935 inch
8 gauge 835 inch
10 gauge 775 inch
12 gauge 729 inch
16 gauge .662 inch
20 gauge 615 inch
28 gauge 550 inch
REMOVING DENTS FROM BARRELS: The man who persistently drops his gun, slams it around in an automobile, bangs it against fences, and uses it to beat his dogs is going to have dents in his barrels. There's no excuse for barrel dents, but sometimes they happen just the same. Most gunsmiths carry on hand a number of steel plugs for removing dents. Usually they do not fit very well in the particular barrel he is working on, and some makeshift method is resorted to. In most cases a plug should be turned up to the
exact size of the bore, which size is ascertained with a sulphur cast taken just back of the dent. The plug should be tapered slightly at both ends as shown in above sketch and should be polished smooth and hardened. This plug may be made of steel drill rod, or it may be of machinery steel, and case-hardened in cyanide. Measure on outside oi barrel the distance of dent from the end, deduct half the length of plug from this measurement, and mark the distance
on a heavy steel rod nearly as large as the bore. Insert plug from breech and drive it into the barrel up to the mark on the rod, partially removing the dent itnd wedging the plug tightly in bore. Now hammer the barrel over the dent with a lead hammer until dent is entirely smooth and plug may be pushed out. It may be necessary to use a copper or brass hammer—if so be careful so as not to mar the barrel.
The best dent removers I ever saw were in the hands of an old gunsmith who must have designed them himself, as I have never seen any others. About three of these, graduated in size by .005 inch for each gauge, would set a man right up in business when it came to removing dents. The drawing that is shown below is almost self explanatory. Two flat pieces of tool steel arc tongue-and-grooved
Was this article helpful?