So i have been saving the funds for a RLL and am getting really close ( Around $10k right now )

But i was a little worried when having talked to a guy at a gun shop one day who claimed he owned a RLL years ago and said it was nearly impossibly to time with a SBR upper and was very unreliable. I have never heard this before, im curious if this guy is being truthful or if he was just trying to one up me when he heard i was buying a Machine Gun.

Is this true you cant use a short barrel with a RLL?
Maybe something to do with higher gas port pressure or bolt bounce?
But if it were bolt bounce couldnt that be softened by using using a heavier buffer?
If my SBR is running correctly why would RLL all of the sudden make it unreliable?

BTW I am planning to put this RLL is a MK18 rifle with a suppressor, any advice is welcome!

no truth at all. my primary host  is a 11.5 upper with and with out suppessor. i also have a 20 set up for it to.

every upper just needs the gap between the it and the carrer tail measuerd and its own paddle and you can rock and roll

now in general shorter uppers are harder to make run full auto but that is not specific to the link it will be the same for RR, RDIAS, and RLL

have to play with buffer weights ect.... as issues will show up under full auto that you just wont experiance in semi, especially suppressed full auto.

My links are currently installed in a 7.5" and a 10.5" and both run perfectly.  The 10.5 runs both suppressed and unsuppressed depending on how I feel on a given range day.

There may well be tuning issues getting a new short upper to run reliably in full auto, regardless of whether it's using an RLL, RDIAS or RR, but nothing that can't be worked out.

10.5" , 11.5,  and 14.5" modified burst kits in two lowers, both function 100% with kns protector and a thicker paddle

My link runs like a Swiss watch on 10.5" Spikes upper.

6" 9mm, 10" 300, 14" & 16" 223s....  Easy as pie. You may need to match a paddle to the upper but that's stone simple