I was going to buy the Adams Arms ,butt now am looking at the Osprey
I will be adding this conversoin to my 20" barrel
Has anyone used the Osprey in a rifle length?
Good ....Bad ?
Hank

Sorry, I don't have the rifle length.  I have two mid-lengths and they have performed flawlessly for several thousand rounds each. I would not presume to beleive the rifle length would perform any differently.

I have their rifle kit on a regular 20" Colt M16A2 upper, and it has been running fine in semi and full auto, both suppressed (Surefire 556FA can) and unsuppressed for over a year. The standard A2 rifle buffer and spring has been fine.

I would point out that the handguards that came with the kit I received did not join together and had a huge gap between their upper and lower sections. They also seemed too big around for my taste. I would recommend either modifying some A2 handguards (which is what I did, to keep the original A2 look) or going with an already compatible set, or one like the MOE which can be easily modified to work.

I also have their carbine kit running fine on a 10.3" Daniel Defense upper with a Levang comp, but I did need to try a few spring tension and buffer weight combos to dial it in for reliable function on full auto.

Mine runs fine.

i have run the carbine length on 16", 14.5" and currently 11.5" all run fine but had to get a standard buffer and open the gas port some to run cheap ammo on the 11.5"

14.5 and 16" I was able to run a h2 buffer with cheap ammo, these barrels had fixed front sights