Countless millions of nuts and muzzle devices have been marred or destroyed by adjustable wrench jaws giving too much and rounding corners. Tip #3 – When you remove the muzzle device and/or existing barrel nut, I’d recommend you use open end wrenches and NOT an adjustable wrench.
Note, the Giessele Reaction Rod works too but just costs more. Click here for a post that provides more details.
You need to apply quite a bit of torque to remove the existing nut and 40 foot pounds to install the Combat barrel nut. Tip #2 – I’d recommend you use a Magpul Barrel ExtensionVise Block – a “BEV Block”. I really do recommend you take just under 10 minutes to learn from them first hand. To be honest, I read the paper instructions that came with the rail and realized it would really help to see what was needed so I watched the above video. MI took the time to assemble a short video for you to understand what is required to install the rail. That’s not going to happen with the Combat rail. In other words, it isn’t going anywhere unlike many rails that shoot loose and all of a sudden you are holding the rail separate from the weapon because it slid off the barrel nut. Combine thee knurling, key and very generous tabs that position the rail on the receiver and this rail is very well retained. Second, and perhaps more importantly, the groove that the key rides in allows the rail to align any way you need it to with the receiver without having to deal with shims and it inhibits the rail from sliding forward. There are two reasons – first, the knurling creates a more anti-slip surface than a smooth surface would. Now you may be wondering why I care about the design of the barrel nut. Here is the knurled barrel nut, the indexing key and the two screws. The first hint this is different from a lot of handguard that simply clamp is that insert in the middle – that’s the indexing key. In other words, you need to unscrew the lower two clamping screws to then remove the barrel nut. The handguard arrives with everything inside. So,I availed on Holiday sales and ordered one from Optics Planet. I have that small tub of barrel nut grease ready. This is the 9.25″ MI Combat rail as it arrived. The 9.25″ M-LOK Combat rail looked good and three things caught my eye – the barrel nut was knurled, they had an innovative means of timing the handguard to the receiver, and it looked good. The name made me think mall ninja but the design is interesting and they did a good job manufacturing the assembly.
I recently was looking for a free floating handguard for a 10.5″ AR pistol build and happened upon the new Midwest Industries (MI) Combat rail series.