Shotgun barrel/mag extender question

I am in the process of doing the same thing. I bought a 18" barrel for my 870. Everything I've read says that a +2 extender will be even with an 18" while a +3 would be even with a 21". Which one are you looking at?

They are not all +2.

If you put an 18.5" bbl on, use the +2.

You may have to grind down the dimple that retain the mag spring, no big deal.



I used the Wilson Combat +2 mag extender and the 18.5" Mossberg security barrel on my 870. They work like a charm.

Mossberg/870 barrel

Wilson Combat +2 mag

Naw, I just kept the bead. It's a short range setup.