So I just put together my AR last night and the only real snag I ran into was getting the MOE hand guard onto my BCM mid-length upper. I eventually got it on after much muscling and aggravation but noticed that the hand guard is rotated like 1/16" too far to the right. At first I thought my barrel nut may be out of alignment (AR noob here) but realized that cannot be the case. Now it seems like the handguard is square with the front triangle handguard ring but the ring is not completely square with the front sight.
I was wondering if this was a common issue? Or else, is this a fix I can do at home or does it require complete upper disassembly?
That’s sorta what i’m trying to determine. It looks pretty clear that the handguard has small nubs on them that index themselves to the spokes of the barrel nut and that’s what keeps it straight and secure…I presume. For some reason, if I install the lower handguard alone, it sits pretty straight. With both on, it doesn’t. I’m worried that if the front triangle handguard ring is not correspondingly square with the rear barrel nut then a railed forend which I plan to run in the near future will not seat right…
Do you mean the handguard cap is rotated to the right or that it’s not parallel with the closest face of the fsb? I had a MOE hg on a BCM upper that sat just like you’re describing. Two actually; 1 factory and one I built. I ignored it and no problems came up when I went to a free float rail. What kind of rail are you planning on?
Yeah, basically that…it seems to be rotated a bit off center. Here’s a pic:
You can see by the tab on the lower handguard piece that it is not exactly straight when lining it up against the sling swivel and etc. I’m presuming that the spokes on the barrel nut dictates exactly how the handguard will sit with no wiggle room. Thus, I’m worried that the handguard still installed because it is plastic and maybe had enough flex so that it still locked up with the rear barrel nut and the front handguard cap…
As far as the railed forend, i’m thinking about just the MI gen2 drop in rail…nothing too fancy.
Are you sure? Cause there is another curved tab like 2mm above it that the cap goes in-between. All the lines in the front seem to be flush too.
So I just tried to remove and reinstall the handguards. I am 99.9% sure I have it in right because there are various tabs and I can see how the triangular shaped cap fits perfectly in place. I’ve always installed it top front, top back, then bottom front, bottom back. I checked the two indexing nubs on the top piece and it is seated properly into the spokes of the barrel nut.
The bottom piece goes in seemingly fine, and it looks like the top piece is what’s dictating how it sits as far as straightness with the rest of the gun.
I can’t figure out what’s wrong…crooked FSB? cap? No idea…everything looks straight except for the hand guards themselves and I have a hard time believing it’s the handguards that are faulty they probably pump out thousands of them through the same mold.
I guess I’ll have to take this to a gunsmith to have it looked at…
Nope. Being that this is a mid-length rifle with a triangular cap, the design on these handguards is different than the design on the carbine length variants.
This is, what, 1/8"? Maybe a 1/4", at most? This is absolutely a non-issue.
If it were a rail or something that you were trying to mount optics to, yes, this would be a problem. But it’s not.
Muscle it on? Just spend the 12$ and get the tool to take them on and off. Should take 0 effort to get handguards on, and def no muscle. Leverage and proper inexpensive tools are your friend.
Well one day I might…and if it is indeed some issue with the upper then it would be nice to get it sorted with BCM before firing the gun instead of going to them hundreds of rounds later…
