What choke for 870 sm 28" barrel?

[BCBrez]

Okay I have a Rem. 870 SM with a 28" barrel.  It has been great at putting long beards down but most of the birds I've shot have been within 20 yards.  The couple that I have shot further out (50 yards) have required follow up shots and a little chasing.  My question is what kind/size choke is ok with such a long barrel, or do I put my 18.5" barrel on with a choke.  Shorter barrel only takes 3" shells though.

[SCDieselDawg]

What choke are you running now? I've spent a little time with the .660 Primos JellyHead and the .662 Hevi-shot Choke. Both shot nearly identical to each other so I would suggest the JellyHead.

[BCBrez]

I have not bought any chokes yet.  I'm just using Rem. full choke, one of the three chokes the gun came with.

I wasn't sure if .660 would be to tight with a 28" barrel or if I should try .665.

[SCDieselDawg]

The .665 may be better in the longer barrel. I didn't run the .660 in any longer than 24". But I did run the .662 in both a 21" and a 26/28" and it seemed to prefer the short barrel so I may have had the long barrel over choked.

[SumToy]

A lot of it has to do with what shell you going to shoot.  665 with Winchester long beard and 31/2 HV13 6&7.  Now Mag blends I like to see little smaller choke.