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Millimeter Help #86560 03/06/08 01:41 PM
Joined: Jun 2004 Posts: 646 West Michigan Dave M. OP Sidelock
OP Dave M. Sidelock Joined: Jun 2004 Posts: 646 West Michigan	What is the Millimeters for a 16 bore and 20 bore?

Re: Millimeter Help Dave M. #86564 03/06/08 02:03 PM
Joined: Nov 2005 Posts: 1,274 Likes: 1 California james-l Sidelock
james-l Sidelock Joined: Nov 2005 Posts: 1,274 Likes: 1 California	Dave 16ga is 16.8, 20ga is 15.6. It can vary due to manufacturing tolerances. A good site for metric conversion is http://www.worldwidemetric.com/metcal.htm Jim I learn something every day, and a lot of times it's that what I learned the day before was wrong

Re: Millimeter Help james-l #86567 03/06/08 02:06 PM
Joined: Jun 2004 Posts: 646 West Michigan Dave M. OP Sidelock
OP Dave M. Sidelock Joined: Jun 2004 Posts: 646 West Michigan	Well, I have a set of Damascus barrels, stamped 16.4 A 16 gauge shell will not go in the breech? Actually it appears to be marked 16.1 over 16.4 Last edited by Dave M.; 03/06/08 02:10 PM.

Re: Millimeter Help Dave M. #86579 03/06/08 02:50 PM
Joined: Apr 2005 Posts: 1,698 Likes: 46 Midlands,England,Great Britain... Salopian Sidelock
Salopian Sidelock Joined: Apr 2005 Posts: 1,698 Likes: 46 Midlands,England,Great Britain...	Dave you need the chamber dimension for a comparison

Re: Millimeter Help Salopian #86581 03/06/08 02:52 PM
Joined: Jun 2004 Posts: 646 West Michigan Dave M. OP Sidelock
OP Dave M. Sidelock Joined: Jun 2004 Posts: 646 West Michigan	Salopian, I can measure the chambers and the bores, tonight when I get home. I'm thinking this is an 18 bore gun.

Re: Millimeter Help Dave M. #86583 03/06/08 03:00 PM
Joined: Dec 2006 Posts: 629 Likes: 1 NW Sliver Sidelock
Sliver Sidelock Joined: Dec 2006 Posts: 629 Likes: 1 NW	One inch is 25.4 milimeters.

Re: Millimeter Help Sliver #86591 03/06/08 03:39 PM
Joined: Jan 2002 Posts: 5,954 Likes: 12 Rocketman Sidelock
Rocketman Sidelock Joined: Jan 2002 Posts: 5,954 Likes: 12	Dave, the chambers may not have been finish reamed.

Re: Millimeter Help Rocketman #86598 03/06/08 04:42 PM
Joined: Feb 2006 Posts: 3,854 Likes: 118 Eastern Pa David Williamson Sidelock
David Williamson Sidelock Joined: Feb 2006 Posts: 3,854 Likes: 118 Eastern Pa	Dave, I believe the 16.1 is the choke. Some of the Spanish guns are marked *16.4 or **18.5 which is like our imp.cyl/mod. In millimeters a 16ga. chamber would be 18.92 A 16ga. chamber is .745, in mm is: 18.92 A 20ga. chamber is .698, in mm is: 17.73 A 28ga. chamber is .626, in mm is: 15.90 Last edited by JDW; 03/06/08 04:43 PM. David

Re: Millimeter Help David Williamson #86627 03/06/08 08:04 PM
Joined: Dec 2001 Posts: 12,743 Lynchburg TN 2-piper Sidelock
2-piper Sidelock Joined: Dec 2001 Posts: 12,743 Lynchburg TN	"Nominal" 18ga is .637"/16.18mm Miller/TN I Didn't Say Everything I Said, Yogi Berra

Re: Millimeter Help 2-piper #86647 03/06/08 09:40 PM
Joined: Jun 2004 Posts: 646 West Michigan Dave M. OP Sidelock
OP Dave M. Sidelock Joined: Jun 2004 Posts: 646 West Michigan	This is what I know so far. Bores are 16.1mm which is .634" They measure .645" 20 gauge is .615" and 16 gauge is .662" 20 gauge chambers are .698" at the entrance .685" at the cone. These are .705" entrance, .695" at cone. So the bores have been honed about .011' from the original proof marks. of 16.1mm The chambers have been honed about .010" from nominal 20 gauge chambers. So, I think it's a 20 gauge, that has had the chambers and bores honed.

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