Surecycle for m4?

[wintwu]

Hey guys, has anyone tried these:

 

http://www.surecycle.com

 

I'm still breaking in my m4, havent had any problems yet but notice when i bull the bolt back manually sometimes it gets stuck at the rear. I know some people have mentioned replacing the spring in the stock.

 

just wondering if anyone has any experience or insight to this.

 

Thanks

[M1014]

never ever think about a surecycle on your gas gun,do not listen to those other people,,they haven't a clue,,,that M4 of yours is so finely tuned that it doesn't need what your talking about,,,read that owners manuall of yours,,the bolt will remain in the rear when the weapon is empty,,,and quit saying yet about your M4,,be more confident and positive,,don't go looking for trouble that isn't there,,

[wintwu]

Thanks M1014, i was more curious than anything. also on my sometimes it gets stuck even when the bolt release tab is not activated (red dot showing)