AR Sponsor
Posted: 8/16/2008 8:04:50 PM EDT
|
I realize that when you install a free float quad rail hand guard, it isn't exactly the same as a true monolithic extended upper receiver, but of course you want the two top rails to look like the are true to each other, right? After installing a MCTAR-20 on one of my carbines a few months ago, I got to noticing that it was very slightly out of alignment, or not exactly "clocked" true to the receiver rail. So, in spite of the thread lock on all the installation screws, I took it all apart and put a slight turn on the barrel nut and put it all back together. I did correctly the slight misalignment to my eye's satisfaction. A day later, I noticed a gap in the side seam on the main clamping part at the base of the hand guard, and discovered that I had stripped out the aluminum threads on the 2 screws on one side. AAAARGH! I guess I should have left it alone, but I bet I'm not only particular person that would want it "just right" How much of a concern is it for optic or sight alignment if there is a slight mismatch between the receiver rail and the handguard free float rail? I just noticed a similar slight mis-alignment on the free float Troy railed hand guard on my M&P-15T upper. I know you shouldn't mount a scope base or eotech partially on on each half or bridging the seam between the two. But what if you use a flip up front sight post on a slightly "off" quad railed free float hand guard? Wont there be issues zeroing the rear sight windage? Any personal experiences or input is appreciated. |
| If you can carefully remove the screws & uninstall the rails, when you reinstall them, take a detachable carry handle & effectively "bridge" the imaginary gap while it's firmly attached to the flat top receiver & the top rail halve at the same time. Resecure all of the mounting hardware & then remove the detachable handle. After this your rails should be pretty close to being in alignment as humanly possible. As far as your bzo being off with a rail mounted buis, it would no different than having a canted fized FSB. Your zero can be confirmed with a marginally canted front sight but I would try to minimize it as much as possible. |
AR Sponsor