If you go to the bumpfiresystems.com page, they have plenty of FAQ's addressed. It might help you in your search.
Since they're a local S. Fla company I've had the pleasure of talking with them at my fav local range a few times. I've even been there with them as they filmed their promo vids posted on their site. They have always been super friendly and able to answer my questions both in person and emails. If I recall, they say that for the system to operate properly on the 15-22 they suggest a 3.5 lb trigger swap, in addition to their stock..
Have fun when you get yours. I know I've had plenty with mine