NUMBERS - NUMBERS - NUMBERS

[Matt Michael]

Today I brought home some calipers from work so that i could take some measurements of my 12ga hammer. I'm hoping some of you experts can shed some light.

First of all the chamber length:
2.565" to a definate ridge line inside the barrel.
Does this mean its chambered for 2 5/8 shells? 2 3/4 fits fine.

Barrel Length:
28"

Right barrel at muzzle: .712 - .707
Left barrel at muzzle: .72 - .716
What does this say about the chokes?

[Bill Murphy]

Sorry, calipers will not measure your bores. You need a bore micrometer as sold by Brownell or Galazan. Price $100 to $125,

[Mike Shepherd]

Bore gauge.
http://www.brownells.com/.aspx/pid=12736/Product/SHOTGUN-BORE-GAUGE

Wall thickness gauge.
http://www.brownells.com/.aspx/pid=20463/Product/WALL-THICKNESS-GAUGE

[LarryAngus]

If a research paper is available that may also tell you the chokes. I was suprised to find that my 16 guage had both barrells at full choke. I always thought the left was full and the right was modified.

[Matt Michael]

Thanks for the links, what about the chamber length. Does this indicate what type of shells it was designed for?

[Bill Murphy]

That is a nominal 2 1/2" chamber. You should probably shoot 2 1/2" shells in those chambers, especially since the chambers have a ridge at the chamber end. Unless you choose to remove the ridge line, paper 2 1/2" shells would be preferred over plastic shells, since the plastic shells are thinner than the paper ones.