.790 is pretty tight for a 8 ga she must be what we all call extra full i hope she is... charlie

Charlie, I hope it is tightly choked. When I get around to getting the wall thickness gauge out to figure out the bore diameter, we will know.

OK, here is the verdict on the Davenport bores and also my method of measuring eight gauge bores when we don't have a bore micrometer big enought to measure the eight, or even a ten. I first marked off the 16" and the 8" depth mark on my $90 Manson wall thickness gauge. I then measured the wall thickness of the Davenport barrel at those depths, from the muzzle. I then flipped the gun over to see if the wall thickness is the same on the other side. I then measured the outside diameter of the barrel with a vernier caliper. The same measurement could be taken with a 1" to 2" micrometer. The wall thicknesses at 16" and 8" are .160" and .145". The outside diameter at the 16" and the 8" marks are 1.180" and 1.140". The bore diameters, calculated by doubling the wall thickness and subtracting it from the outside diameter, are .860 and .850. Allowing for errors in measurement at any of the many points measured, done on a bench with no vise for the gun, I would place the bore diameter at an estimated .855. A more careful measurement of the muzzle at .800, rather than the previously posted .790, would place the choke measurement at .055, a nice full choke for an eight gauge. Test fire to come when the snow melts off the pattern board area.

glad she was full choke bill can not wait to here how it patterns..charlie

Bill if you keep an eye on ebay you can find a set of used pin gauges that go from .750 to 1.00" pretty cheap sometimes. I think I gave $25.00 for mine.

Thanks, Wayne. I have pin gauges, but I like the idea of getting measurements down to the 16" point. The pin gauges may not even go beyond a long choke. With the Manson gauge, you can also come in 16" from the breech end. By the way, pin gauges and micrometers are a simple way to measure .410 bores, since most of us don't own a .410 bore micrometer.

i would think the first shot from an 8 gauge would take care of the snow on the pattern board :corn:

as for your math- agreed- as long as you have two of the variables - you had wall thickness and outside radius, you can get the third.

Before I acquired my gauges I bought a gun I wanted the wall thickness of. I borrowed a bore gauge, measured the outside and did the math. Later when I assembled my set of gauges I repeated the exercise and then measured the walls- the numbers agreed. just don't tell the late Mrs Peterson I actually used the math she taught me in school - the shock would kill her again.

It sounds like an interesting gun....... but

Hey Bill!

Send the gun to me and I"ll shoot photos and post here for all to enjoy. Oh, I won't even charge you for the photos. Consider them a donation to our PGCA friends. :)

Mark

Charlie and Mark will be pleased to know that, recently, I picked up a Davenport 10 gauge with 40" barrel in high condition, about the same as the 32" 8 gauge. I couldn't attend the auction where the 40" gun was being sold. Next day, I asked a friend if he attended the auction and what did he buy. He did attend and said he bought a long barrel single. Wow, what luck. We reached a quick deal and I have the gun.