The barrels of most 311's are marked with letters indicating choke constriction. The most common are M=modifed and F= full,but others are also used , 30" barrels are considered "Waterfowlers"length and are often choked Full and Full. If the barrels aren't marked then you will have to measure them. In 12 gauge from a standard bore diameter of .729 then Full=.693, Modified=.711, Improved cylinder=.720 and Cylinder Bore=.729. To install internal chokes of a standard of Winchoke or RemChoke you will need a wall thickness to allow for a thread of.812-.814. There are "Thin Wall types available that will allow for up .020 lesschoke thread diameter.Brownells recommends that wall thickness be at least .015. This is minimum, to be absolutely sure take or send your barrel to a 'smith that specielizes in this work for evaluation PRIOR to shortening of the barrels. You can find a list of Gunsmiths that do this on the web site. www.brownells.com Gunny
Numrich Archiver
Joined: February 2010
Posted: May 25, 2004 10:18 AM
The barrels of most 311's are marked with letters indicating choke constriction. The most common are M=modifed and F= full,but others are also used , 30" barrels are considered "Waterfowlers"length and are often choked Full and Full. If the barrels aren't marked then you will have to measure them. In 12 gauge from a standard bore diameter of .729 then Full=.693, Modified=.711, Improved cylinder=.720 and Cylinder Bore=.729. To install internal chokes of a standard of Winchoke or RemChoke you will need a wall thickness to allow for a thread of.812-.814. There are "Thin Wall types available that will allow for up .020 lesschoke thread diameter.Brownells recommends that wall thickness be at least .015. This is minimum, to be absolutely sure take or send your barrel to a 'smith that specielizes in this work for evaluation PRIOR to shortening of the barrels. You can find a list of Gunsmiths that do this on the web site. www.brownells.com Gunny
There are no choke identification marks on the Stevens Model 311 Series H shotguns / You can determine the standard chokes by the barrel length, 12 Ga. 24 & 26 inch IC&M, 28 & 30 inch M&F, 20 Ga. 24 & 26 inch IC&M, 28 inch M&F, 16 Ga. 26 inch IC&M, 28 inch M&F, 410 bore 26 inch F&F /
Numrich Archiver
Joined: February 2010
Posted: May 25, 2004 12:15 PM
There are no choke identification marks on the Stevens Model 311 Series H shotguns / You can determine the standard chokes by the barrel length, 12 Ga. 24 & 26 inch IC&M, 28 & 30 inch M&F, 20 Ga. 24 & 26 inch IC&M, 28 inch M&F, 16 Ga. 26 inch IC&M, 28 inch M&F, 410 bore 26 inch F&F /
