Larry's a great guy, but I'm not too pleased with mine either - I actually have had two, the first one would come loose after every mag. This one generally stays on there, though you usually do have to tighten it after the first mag as the barrel warms up (being that the barrel and f/s and expanding at different rates). Even this is kind of a pain, considering you have to remove it every time you clean the pistol. I would imagine it would be a bigger pain with the locktite.
The current either appears to be of a different design, or has a manufacturing defect. I doubt it is the latter, as Larry was going to find a barrel in his shop that my original one was loose on, and find a good match based on that.
The original one had the cuts straight across from eachother like this:
(edit: Bleah - looks like the website removes my whitespace. If you look at the original cutouts, they form a perfect cross. The new one, each cutout if slightly offset to the side, for example the top cuttoff is slightly left of center, while the bottom is slightly right, etc.)
. |
. -- --
. |
The current one is like a bit offset, like this
. |
. -- __
. |
Ok, they so the representations are bad, but you hopefully get the picture. I'm not talking about the cuts being the 0, 90, 189, 270 mark either as H&K does not time their threads so that is pretty much impossible.
They are supposedly based on the vortex f/s, but I'm pretty new to AR's so I don't really know which the proper design is. They also do not match H&K's finish on the USP - in fact, the one I have now is sort of purple.
The machine is also pretty rough - lots of mill marks on the insides of the cuts. Overall, I don't think it is a very "polished" product, if you know what I mean. The variance on the two examples I had were so great... Not exactly what one would expect after paying $100 for a hunk of metal.
It does, however, significantly reduce muzzle flip. However, while I haven't had a failure when using it yet, I would think that it has to effect reliability. Without the f/s, my tactical throws all the brass in a nice, neat pile, when it is attached (happed with both of mine), the brass is ejected with MUCH less force, and it pretty much flies all over the place, many times back into my face. At the range it is fine, because you are wearing glasses, but if you ever needed to use it in a a real life situation, I would imagine you wouldn't want hot brass flying in your eyes.
Rocko