Questions mostly about 20 gauge 870's, just trying to verify what I'm seeing on various sources which don't seem to differentiate between the gauges. 870 shotguns are called LW, Magnum or no particular designation.

870 LW = lightweight. In the 1100 they made an LW for a while, then changed the name to LT. From what I gather barrels for the LW will only fit LW guns, LT barrels fit any 1100 receiver. So - is this the same for the 870? Or if not, what does the LW denote about the shotgun? Different material in the receiver, different barrel profile, ???

870 "Magnum" marked on the receiver - I gather only 12 gauge guns are so marked and means it will handle 3 1/2" shells.

No particular designation beyond "Wingmaster" - all 870 20 gauge receivers will handle 2 3/4" and 3", the barrel marking designates if the barrel's chamber will handle both or only 2 3/4".

Sound right?

There wasnt an LT version of the 870, just LW. The LW used the small frame and has been the only frame used since 1978. That Special Field used the same frame but the barrel banger is in a different position so the two are not interchangeable. I'm pretty sure the field guns were chambered for 3" shells from the start. Competition guns may have had 2 3/4" chambers but am not positive.

Prior to 1978, the 20 ga guns were built on 12 ga frames. Some 20s may have been built on the small frames prior to 1978 but I think those were mostly sold as sets. Those stamped Magnum on the receiver were chambered for 3" shells those not stamped were chambered for 2 3/4" shells. The magnum designation was dropped after 3" chambering became standard though I don't know off hand when that was.

I have two of the large frame 20s and they are soft shooting guns for the most Part. One is set up as a slug gun and the other a field gun. I don't use the field gun much but it was my only shotgun for more than a decade.

It’s large frame or small. IIRC the s/n ends in X for a large frame.

passport is correct. my 20ga Wingmaster S/N ends with an X. No vent rib on either barrel[26" Imp/Cyl, 28" Mod]. It's a '75. It's 2.75" chamber only.

Thanks to all you guys. This is excellent information, just what I was looking for.

Some dove and target shooters still prefer the large frame 20 ga. Less recoil.

Jack

Love my old 20 ga 870 LW Magnum, I have a full and mod barrel, saw an IC barrel for sale but have not dropped the hammer on it yet. I mistakenly bought a 20 ga LW Special Field barrel, as mentioned above it does not fit, so I passed it on to a buyer on the Classifieds.

The serial suffix will be X or N for a 20 gauge on a 12 gauge frame. The suffix will be K or U for a 20 gauge lightweight frame.

Another point... the ejector is the only difference between the 2 3/4 and 3 receivers. A 3" barrel will fit just fine on a 2 3/4" receiver, but the empties will hang up on the front of the ejection port.

In the old days they refused to sell 3" ejectors to anyone except their warranty centers.

It is easy enough to drill them out and move them back 1/4" so they will not eject empties until they will clear the port.

On 12s the Magnum may designate the 3" or the 3 1/2" depending on the age. 3 1/2" receivers are different in the length of the ejection port and a 3" magnum will not allow moving the ejector back 1/2" for clearance.

Magnum is a 3" chambered gun and Super Mag is the 3 1/2" chambered gun

Yup, you are right. Thank you.

I don’t think 12 ga magnum receivers will necessarily handle 3.5” ammo. I believe that 3.5” receiver is a super magnum or something like that.

Sitka and others, my older 12 ga 870 has an aftermarket 3" light weight vent rib, choke tube barrel attached. It ejects 3" fired hulls just fine. I did install the available, at the time, flex tab kit (an anti jam modification). It may have the needed extractor. I don't know. No modification to the ejection port.

I love that old gun. It has a Decelerator and I engineered a bit of cast off into the stock. It fits nicely. I looked it over two weeks ago to make sure SIL is taking good care of it. It lives at the kids' ranch so I don't have to haul guns to and fro.

Good shooting,

Jack