[ArtS]

I'm sure this has come up before, but I was giving the subject some thought while arranging for a barrel set to be refinished. I have three Parkers; a pretty light 16 DH, a 12 GH with short barrels and a 10 Lifter at about 10 pounds.

The 16 has very light barrels and a total weight of under 6 pounds. Rough barrel weight was 3 pounds even and the barrels now weigh 2 # 9 oz. Bore measures .664.

I don't have the exact weights in front of me, but the 12 has bores of .729 and the barrels weigh 8 oz less than the rough weight. The 10 has bores of .795 and the barrels weigh, again, exactly 8 oz less than the rough weight.

At first I was really worried about the 10 ga, since I wanted to have them cleaned up internally and was amazed at the bore size. I then measured the barrel walls and found them actually quite thick, That's when I measured the other two guns and found that all three guns with total weights of 6 to 10 pounds had barrels (within 1 oz) of 8 ounces of their rough weight. A whole evening searching The Parker Story revealed that the older guns were bored to work best with thin wall brass shells, and most of the 10 gauges had 9 gauge barrels. The 12's were generally 11's. According to the book, there was finally an official change noted in the late 1880's that the barrels would in the future be true bore size unless otherwise requested. If the larger bores were requested, they would be stamped with an "o" for old or overbored.

Examples were given of original guns with the bore measurements and the 10 gauge measured was in fact .795 or so.


My question is how much variation was there in this relationship? A lot of statements are made about how the workers adjusted weights and balance by removing more or less metal. However, the three examples I have would appear to support a system where, if there was a request for a particular weight, a set of barrels would be pulled from inventory which had a rough weight of 8 oz more than needed to hit the target weight and they were then all struck in a similar manner.

It would be interesting to know the results of a larger sample of guns to see if this relationship varied. Only barrel sets that still had close to their original bore size would be relevant.

I also wonder if when putting together low pressure loads for these old 10 gauges, it may be better than using 10 gauge shot cups to use 9 gauge felt and card wads.Asking a .775 plastic wad to seal a .796 to .800 bore at low pressure is asking a lot.