I have a stevens model 311(actually a sears 101.7,same thing) and I don't know what chokes it has. It is a 30" barrel and from my gun traders guide I know that it is either a full/full, modified/full, or a modified/cylinder. Can anyone tell me how to figure it out before dove season ends? The only marking is a "D" with a circle around it and the letters "YP" next to it. Above the "YP" is a sideways"V"

I have a stevens model 311(actually a sears 101.7,same thing) and I don't know what chokes it has. It is a 30" barrel and from my gun traders guide I know that it is either a full/full, modified/full, or a modified/cylinder. Can anyone tell me how to figure it out before dove season ends? The only marking is a "D" with a circle around it and the letters "YP" next to it. Above the "YP" is a sideways"V"


The only real way to know is to pttern the gun...even if the barrels were made to be modified back then, modern ammo may just pattern full....or cylinder...never really know until you test.

Can get the degree of choke from measurements...but reallly need to know the bore diameter AND the choke diameter. Even with the numbers in hand, the barrel's pattern has the last say-so.

USUALLY 30" barrels on a 12 will be either full-and-full or full-and-modified. There were believers in mor eopen chokes back then, but were a lot fewer of them.

Any gunsmith that does much work on shotguns should have an inside bore mic. That'll give you a good running start on the answer.... keeping in mind that chokes have gotten a little looser over the years, as improvements in shotshells like one piece wads tightened patterns.

I forgot to mention that it is one of the choke combos because I can tell by looking at the barrels that one is tighter.

The old, very rough, rule of thumb is that a dime shouldn't drop through a full choke barrel. This assumes that the dime actually measures .700 inch, and the barrel dates before plastic wads. As stated above, the pattern board will tell the truth.

Bye
Jack

The chokes on your 311 should be modified and full. Thats what mine is anyway.