[Mellowmoods]

Hey everyone. I'm a new member with a new SU16A. I just stripped the unit for its first cleaning and am unable to get the piston head to line up easily with the gas head. I have watched videos and searched online and can't for the life of me figure out what is causing it to not line up.

Anyone else have that problem and know the solution?

 

[IamScotticus]

figured it out yet?
Is this happening after you get the bolt and charge handle in?
I have found that when inserting the BCG into the upper, you must try to keep the rotating bolt fully extended forward so the cam will inset right.
For me, this involves sticking fingers and things in the eject port and underneath to keep the bolt forward. The only thing more frustrating is a shotgun action. I swear.

 

[Mellowmoods]

Thanks for the reply. Well... I forced it with my palm down to insert into the gas head. Ironically... once it was in it moved in and out correctly. I think that because the locking tab was straight up (which it needs to be to fit through the hole in the upper) it was not exiting the exit point which was causing the whole part to be a bit high (the height of the lock tab).

I think you are right and that this can be resolved by pulling the recoil spring tube forward a bit while pushing the BCG into place. This will allow the lock tab to exit the upper before the BCG is seated. I'm pretty positive this will resolve the issue but will test it out tonight. Thanks for the insight!

 

[zaitcev]

This question arises once in a while, and at some point I filmed a video about it. In which I pretended that I know the answers, but later I found that this problem can be causes by a multitude of reasons. A bunch of things have to much just right: the position of the bolt in the carrier, the dust cover, and the locking tab on the tube facing up. It's not really as easy as the video makes it out. Still, maybe it was one of those you mentioned: