magpul sights and heat

[Creeky73]

I am considering the gen 2 magpul sights (when they are finally released), mainly because of cost and I do like the idea of color coordination. I would be using the front sight on top of an Adams Arms piston gas block, and I am wondering if I should be concerned about heat from the gas block melting or deforming the sight. Anyone have any thoughts?

[Optimus Prime]

They advised against mounting the Gen 1 sights directly on gas blocks, I'd imagine it'll be the same with the Gen 2s.

[rebelEMPIRE]

Even if the composite material does not melt, the fact that they are plastic will mean the material will expand a great amount under heat. Which will inevitably throw off your elevation, especially at longer distances.

-rebelEMPIRE

[federalist22]

If you tighten the MBUS sights until snug, not incredibly tight but tight nonetheless, over time they will split right at the rail retention point regardless of where they are mounted--I have on rear and one front (on different rifles) that have done this. Nice concept, the MBUS, but I will probably go back to metal varieties.

[Creeky73]

I think that last post is enough to steer me away from the MBUS even for the rear. I know the price is right on them, but if I am gonna have to buy something else after a while, I might as well get something else to begin with. Guess I am back to the Larue/Troy offerings...

[Optimus Prime]

Not that I don't believe you, but that is the first I've heard of that problem, even after hanging out on the Magpul forum on ARFCOM for quite a while. Have you talked to Magpul about it? I've found they have pretty good costumer service.

[Eric]

Interesting. We have a few guys running them on duty weapons and I have not seen that crop up.

[Stickman]

I think that last post is enough to steer me away from the MBUS even for the rear. I know the price is right on them, but if I am gonna have to buy something else after a while, I might as well get something else to begin with. Guess I am back to the Larue/Troy offerings...


I've run the MBUS as BUIS on my duty weapon and never had an issue. On the flip side, I've had two Troy rear BUIS go bad on me. Granted, I'm not easy on equipment....

[Kitty]

I've run the MBUS as BUIS on my duty weapon and never had an issue. On the flip side, I've had two Troy rear BUIS go bad on me. Granted, I'm not easy on equipment....

Second that...well, not on my duty gun but I've played with them and not heard of or had any problems.

Every last piece of gear out there has failed at some point, and you won't have to look far to find someone that hates it and thinks it's the worst thing ever. Every optic (every aimpoint, every eotech), every BUIS (troy, MI, YHM, anything...). Literally everything.

Conversely every piece of gear will have someone stand by it through any criticism regardless of 'actual' quality.

The important thing is that you are comfortable with it and you've done enough to verify that it does what it's supposed to.

If it helps you sleep better, LOTS of 'real' shooters are using MBUSs.

[federalist22]

Don't get me wrong, I love Magpul, everything but the MBUS--I have about $2K wrapped in in Magpul parts/gear. I have not talked to them about the issue because for the price it is easier for me to just move on, but that might not be the case for someone else so I encourage the buy once, cry once approach. Like I said, nice concepts, the MBUS, but when you think you have it snug on the rail and start shooting and it falls off after a few hundred rounds it makes you wonder--then upon inspection you see that the rail claw is split at the seam. I can post pics if someone wants to see. LOTS of real shooters use standard A2 sights and fixed front sight posts. I will likely buy MI, BCM, LaRue, or Troy to replace my MBUS on those two rifles.

[Quib]

Could the cracked MBUS, fall into the same category as the MaTech BUIS? A lot of folks criticize the MaTech with its mounting plate cracking during installation, when the issue was not with the gear, but with the user failing to follow the installation instructions.

No offense Federalist, but did you follow the MBUS install instructions?

Another thought; if the MBUS screw is having to be drawn down that tight simply to secure the sight, that it cracks the frame of the BUIS, this would make me wonder if your upper receiver rail is out-of-spec.

One of the biggest problems I encounter on a daily basis as a QA Inspector, is getting people to simply follow the maintenance manual procedures.

[federalist22]

If the upper rail is out of spec it would be a Seekins Precision upper receiver for the rear and DD Omega Piston for the front sight--I doubt it in both cases. No offense taken. I followed the instructions. The MBUS might work for some, but as much as I am a fan of Magpul I will not make the MBUS mistake again--they're just not for me. Also, they do not crack immediately, but over the period of about 9 months in which I put about 2K rounds through one rifle and about 600 through the other; however I don't feel that the round count matters here.

[Quib]

Thanks for the update.

I don't have a lot of experience with the MBUS yet, and was leery at the thought of purchasing a polymer BUIS. With that said, I feel pretty confident in the design of the MBUS, and in how it mounts. I will keep your experience though in the back of my mind during PMCS.

[Creeky73]

Stick, exactly what went wrong with the Troy units? I felt pretty confident about those as my backup plan to the MBUS. While I don't want to seem like one of those cats that lets the guys in the forum make his choices for him, I do trust the input of the regulars on here. I doubt if my weapon would ever see the same abuse as those of you who use them every day for your jobs, but I would like to build it as if it would, and I don't want to buy parts twice.

[Stickman]

Stick, exactly what went wrong with the Troy units? I felt pretty confident about those as my backup plan to the MBUS. While I don't want to seem like one of those cats that lets the guys in the forum make his choices for him, I do trust the input of the regulars on here. I doubt if my weapon would ever see the same abuse as those of you who use them every day for your jobs, but I would like to build it as if it would, and I don't want to buy parts twice.


I have no doubt my issues were freakish, and my point isn't to complain about Troy. If you like the Troy BUIS, buy with confidence.