870 LW Magnum Vent Rib Barrel No choke designation Coded?

[karisk12]

Hi.
I'm looking at a 1976 870 20 gauge LW Magnum. The barrel appears original. It does not say IMP or MOD or FULL on the left side of the barrel. It has a U then KI which I believe is the date and then the number 5. Any ideas how to tell what choke it is?

[Virginian]

I would say I don't believe it, but I do. Remington doesn't use codes, it is supposed to be stamped Imp Cyl, Mod, or Full, unless it has choke tubes. I am assuming you looked at the muzzle and do not have tubes, and that 'I' doesn't stand for 1988 instead of 1976. All of them produced in 1976 would have had gloss blued metal and gloss walnut stocks with fleur de lis impressed checkering. The tubes have the choke written on them. If it is a 26" barrel it is most likely an Improved Cylinder, and if it is a 28" it is most likely a Modified or Full. All you can do is measure it. The only way to know what it will actually do is to pattern it, but you will know what the nominal choke is anyway. This should help:
http://www.briley.com/2009/chokeconstrictions.html
A wealth of other good information on that site as well.
Oh, nominal 20 gauge bore diameter is 0.615".

[Wulfman]

For what it's worth.........
I took my dial caliper and measured the bore at the muzzle of two of my 20 gauge shotguns.......a Remington 870 28" full choke (coincidentally, also made in 1976) and a Savage/Stevens 311E F/M.

The measurement on both full choke barrels was 0.600" and the modified barrel on the double measured 0.615".


Den

[Virginian]

My 1977 Full mikes right at 0.5915" .