I've read about 1/2 of newarguy's review thread (i'm on page 5 or so :)) and it's implied that the FIRSH probably isn't a good platform for optics to mount to.

My question: has anyone here actually used the setup to mount an aimpoint or EOTech to? What kinda use has that setup seen (from benchrest to ninja stuff in lil desert towns)? If you shoot alot, does it get hot enough to melt your EOTech?

Me, I don't have full auto, so the heat is of limited concern, tho I've burnt myself on my bbl numerous times. I would like something I can puch my EOTech out a bit further on and stick a vertical fore-grip on, but if I'm gonna be pulling the dot down every time I grab the fore-grip, I'm not too psyched.

Thanks for any info...

I don't know why this is implied.  On a properly installed FIRSH, or any other free float tube for that matter, applying torque to the tube will cause the barrel nut to unscrew before the tube slips.

I had this set-up on my rifle and never had any issues with it coming loose, or any heat related problems during use.
[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=10916[/img]

It worked great the whole time I had it, but I did find all the added wait a problem. So I sold the Firsh with the SF light and fore-grip with another AR I was selling. I then replaced the whole set-up with a SF M500A.

I have one mounted on one of my rifles. I use a one piece scope mount with 3x9 attached to a flat-top upper. I set the mount so it attaches the upper and the FIRSH to get the proper eye relief. Everything lines up fine.

No problems here.

Do you guy's FIRSH's top rail line up completely with the flat-top upper's rails?  My FIRSH top rails are about 1/16" lower than the upper's rails.  My upper is a DPMS upper if that's any help.  

Ghost

Was at a shooting class where we were doing a lot of shooting. A friend was using my rifle withthe FIRSH. Later in the day we were doing some shooting from the slung position (both African and American carry) and the FIRSH was heated enough to have burned him. The heat is an issue if you will be doing any shooting for any extended periods of time. Any aluminum handgaurd will absorb and retain the heat. If this will be a problem for you or not depends entirely on how you use your gun. But it is a problem with ALL aluminum handgaurds.

As for mounting optics... I have not had an issue with it myself, but thats only because I just cant bring myself to mount an optic to it! The FIRSH is better than many other in its class like the BMAS one and the C-More, because the FIRSH uses an additional tention screw at the bottom rear... but it is still only tention and nothing is locking it on or in place. So it *may not* be a problem. Im just not reallt at ease doing so unless I know it *will not* be a problem. And for that type of assurance, you will need a SIR, a RAS II, or a FF RAS.

I have a Rock River A3 upper and it lines up. Like i said above. It mounts the two together for a more secure fit. It provides another place for the FIRSH to lock down.

Does the FIRSH thread to the new barrel nut and then clamp?

From the picture I have seen, looks like it’s a slip fit between the handguard and the barrel nut.

Looking far a little more room forward for my EOTech......

TWW, the FIRSH barrel nut is threaded on its entire exterior.  The tube then threads over that and has a screw that you tighten down so that it holds in the correct position.  

I use FIRSH tubes with DPMS flattop uppers.  Like Ghost-Shooter said, there is a slight difference in the height of the rails, but that hasn't prevented me from installing scope mounts that span the gap.  In fact, I think I've got the same setup as PVFD304.  I'm using RRA 1-piece mounts and install them with the front cross-screw in the rear-most slot on the FIRSH.  The slight difference in height doesn't interfere with mounting the scope.