Hello there -

I just bought my first 870 (I came over from the also excellent Winnie 1300) and ended up getting the basic Tactical. I ordered a Rem slug barrel online - 20" smoothbore -and I just dropped it in.

An issue: the barrel is fully seated but does not 'lock' in, i.e. I can manually disengage the barrel from the receiver quite easily. This seems... problematic.

The 18.5 tactical barrel I just took off of it has a belted groove near the receiver end that seats in the receiver that the slug barrel lacks, as well as a shallower slot opposite the receiver's opening. Is this what is causing the slide-out?

Would a mag clamp out by the mag cap (safely, sturdily) rectify this?

Is there some basic Remington law/lore that I'm glossing and it's an easy fix?

Any suggestions?

Thank you in advance.

Scotch that. I just learned this about the 870 Tactical: " Due to the location of the barrel ring on this model you can not change to other Remington Barrels as this is the only one made for this weapon."

Now I know.

Sorry for the delayed post but I was just going to mention that you can't switch out the barrel on the "tactical" model. If you have a spare moment would you mind posting up some pictures of the two barrels so that we can help members in the future that may have this issue as well.

all guide rings with the exception on a mcs model are all in the same place, unless you bought a 2012 version of the single tube 7 shot, your barrel will fall right in. when you say its not locking in can you explain what it is doing? all guide rings on 870 barrels are 11" front the edge of the barrel to the rear of the guide ring.