Saker 7.62+brake attachment question

Trust just got a Saker 7.62 and the three port brake attachement. haven't mounted the brake to a rifle but just in initial fiddling it appears that the suppressor won't fit all the way over the brake. It's like the diameter of the brake is too large. I have read the manual and made sure the three teeth on the rear can attachement are rotated as far as possible out of the way but it's like they don't retract fully.

For any of you who have this setup, does the can slip without resistance over the brake or do you have to push against spring tension or something?

thanks