Recently, Impact Weapons Components sent me a Mount-N-Slot Hand Stop and Mount-N-Slot Radial Universal Light Mount for my Midwest Industries Gen2 SS Series free-float handguard.Author’s note to readers: Always safely unload your firearms before cleaning or working on them. If you’re putting accessories on an AR-15 handrail, replacing a muzzle device, or working on a sight, go ahead and detach the upper from the lower. This will simply add a layer of redundant safety and help you avoid any unintentional body piercing.
The Mount-N-Slot accessories attach by way of a screw that goes through the accessory, a space in the handguard, and then into a threaded tab. When the screw is tightened, the handguard is clamped between the tab and the accessory, ideally resulting in a firm fit. The tabs included in my order looked a bit smaller than the ones I used on my Daniel Defense MFR and I expected them to be just as easy to use.
I was wrong. The tabs are just a hair thicker than the slits that run along the MI Gen2 handguard, which means you have to insert the tab before it’s threaded onto the screw. It is difficult and frustrating to push a screw through the hand stop or light mount, through the handguard and attempt to thread it onto a tiny tab. It was maddening to try to get the tab positioned just right. To thread the screw onto the tab, I had to hold the tab in place with an Allen key inserted through a side slot. I used the Allen key to apply downward pressure on the tab so that I could thread the screw into it.
I can’t count how many times I’ve dropped these damn tabs.
I would really like to have the Universal Light Mount at the 10 o’clock position, but that simply doesn’t look possible. The Midwest Industries handguard is so thin that in order to mount the light in that position, I’d have to remove the Troy folding front sight I have on the continuous top rail. While the Mount-N-Slot light mount would indeed attach at the 10 o’clock position, the ultra-slim profile of the rail limits mounting option. Opting to mount the light on the side, I attached the mount and almost immediately noticed that the screw was only a millimeter or two away from touching the barrel. That far away from the receiver, any flex would result in the barrel striking the screw.
The culprit is the type of screw I was using. The screws provided with the accessories are longer than the screws MI use with their rail attachments. Finally, I got the flashlight mount on in a satisfactory manner. I couldn’t put a screw through either of the holes in the front, as it would protrude too far into the interior and risk contact with the barrel. Thankfully, there are several different mounting slots in the Radial Universal Light Mount, making it extremely versatile in regards to mounting options.
Use the Blue
Though I tightened the screws firmly with the provided Allen wrenches, I did not use any Loctite. Within 30 rounds, the light mount became loose. In another 30 rounds, the rear tab of the light mount worked free of the handguard and came completely out. Also in the first 60 rounds, the handstop became loose, even though it was screwed directly into a threaded hole in the handguard.
I removed both the light mount and hand stop and applied blue Loctite to the mounting screws. I then re-attached them to the handguard and headed back to the range. I put 90 rounds through the weapon with absolutely no perceivable shift in the hand stop. I then had 5 students handle and fire the weapon. The rough jostling did not seem to affect the hand stop . Likewise, after application of blue Loctite, the light mount functioned flawlessly, with no perceivable shift.
Installing these things can be a pain. However, with a bit of patience and some manual dexterity in the fingers, it can be done with a minimum of fumbling and cursing. Use of Loctite or Vibratite is an absolute must. If you can do all of this, then you’ll be pleased with the lightness, durability and low profile of the Mount-N-Slot products.
By Allen Michael Cosby