10 ga choke question

[lowoctane]

Have a American Arms double that belonged to my mentor and I'm thinking about bringing to the fight this season. Thinking about lead #6 as it works so well in my 12's, but need suggestions on choke size and manufacturer. Thx in advance! 

[4nolz2]

 Is it threaded?

[lowoctane]

yep. not sure of what thread pattern tho. 

Research indicated Invector style choke tubes...

[deadbuck]

I have seen constrictions as tight as .680 in the 10 gauge, but .690- .720 seems to be the preferred range from what i see

[potter]

I have a double I like a 685 in the top for a tight pattern and a 750 in the bottom. I'm using tss 8&9.