Modern Sporter builds Q&A

[Kratos]

Had an issue doing a test fit with both spare handguards I had on hand.

They're Aero Precision's, never had issues with them in the past. These guards are for milspec AR uppers so they weren't gonna fit this build, but the nut should still thread on fine. I used Aeroshell 33 and stopped pretty quick but both barrel nuts I have here are giving me trouble and are threading slightly off. I've never seen this before, any ideas?

I've got other hand guards here but don't feel like pulling anything else apart to check with a 3rd or 4th barrel nut... I've got a different HG coming for this gun but it's a ways out yet.

Which Aero handguards? My MLOK Quantum’s all went on perfectly, they use the BAR nut. Anti-rotation tabs even line up.

[propliner]

One bad nut may have buggered up your threads and made the second nut feel the same.

[Bombsquad68]

Second barrel nut won't thread any easier than the first past the first few threads. One Atlas S-One, one Atlas R-One, got one for me and one for a buddy's AR build.

[ATRS Shaun]

We cut the threads on the uppers for a tight fit, and exactly to spec. We had a gentleman bring in a barrel nut late last week with the same issue, an aero precision one. We ran a tap into the barrel nut and only the first thread appeared, to our best guess, to have a build up on it of the coating they're using. If you're in town bring it by we can do the same. If you're not I'd try a wire brush on a Dremel in the threads of the barrel nut to make sure there's no "gunk" stuck in the threads from their coating process.

[ATRS Shaun]

After the tap cleaned up the first thread in the nut the thing went on ridiculously smoothly.

[Bombsquad68]

We cut the threads on the uppers for a tight fit, and exactly to spec. We had a gentleman bring in a barrel nut late last week with the same issue, an aero precision one. We ran a tap into the barrel nut and only the first thread appeared, to our best guess, to have a build up on it of the coating they're using. If you're in town bring it by we can do the same. If you're not I'd try a wire brush on a Dremel in the threads of the barrel nut to make sure there's no "gunk" stuck in the threads from their coating process.

Thanks for the insight and offer, I will check them out a bit closer at my shop tomorrow and see if the Aero nuts have any wierdness going on with the coatings. Would love to check out the ATRS facility next time I'm in Calgary.

[anoxia]

I've also seen the results of people trying to thread an Armalite barrel nut onto a DPMS receiver.

[Adamg_55]

Can anyone with a maple ridge handguard comment on how it matches the modern sporter? I saw a pic of one on an slr and it didn’t really match the anodizing? Or the color. Not sure of the correct terminology.

[Jeffv]

I have the maple ridge hand guard. The color is off a touch. I would post a pic but I don’t know how. I can email you a pic if you want. I am going to keep it for now but I might just cerakote the whole gun so it matches.

[Jeffv]

My barrel nut was also really tight. I greased it up and then used a heat gun on the nut to expand it slightly. I would heat it up when it’s not on the gun because I don’t know if heat will damage the upper.