Bizerk O-ring?

[wLazar0]

I have a 10" Bizerk Pro for my Bushmaster B2K2.

What size o-ring do I need for this barrel?

[Arizona Kid]

Equation's having new o-rings made up for the Pro Bushmasters since they had to change the diameter of the o-ring groove to accomodate the sleeves. these will be available in about 2 weeks.