Mag extension fitment question

[Moser40s&w]

So I just bought a magpul edition cerakote rem 870.
Like it. Like the sight and the magpul furniture fits good.



This waste extension I was looking at


Question I have is can I fit this +1 mag extension without it coming to far up the breacher choke ?
Done a it replace the mag tube cap nut? And do I need a longer spring?

Thanks cgn

 

[EL34/6L6]

Great gun, I have the same one in black.
I explored this same question, only without the TAC choke installed.
Using a +1 with the TAC choke installed will not make the tube extend longer than the barrel. A +2 might though.

I want one for mine, but I think the +1 will make the tube longer than the barrel with the TAC choke off.
In the pic, you can see the modified choke I use instead of the TAC choke. Less initial spread, more concentrated shots.

As far as I know you get a new spring with the extension. It will replace your original mag cap too.

 

[taprack9]

The +1 should be fine with the tac choke not used, it will replace your current mag tube cap