Griffin Low-Pro M-LOK Rail

[Disciple]

Someone mentioned these (https://www.griffinarmament.com/ar15-firearms-parts/ar15-rail-systems/) in another thread. The sale price is hard to beat. Are they any good? Comparing to MI Combat Rail and BCM MCMR.

https://cdn11.bigcommerce.com/s-lbyqmcyjkm/images/stencil/1280x1280/products/173/3520/LPR15__91234.1682977594.jpg
https://cdn11.bigcommerce.com/s-lbyqmcyjkm/images/stencil/1280x1280/products/173/3516/LPR105-3__72790.1538423421__02940.1682977307.jpg

[ViniVidivici]

If they're anything like everything else Griffin makes, they'll be outstanding.

[Disciple]

If they're anything like everything else Griffin makes, they'll be outstanding.

I took the gamble. I hope you're right.

[bruin]

I recently installed a 12.5" on a .22 upper. The other two rails you mentioned are ~$150 for ~13", so the Griffin on sale is attractive. Strangely, the 13.5" is the only length out of seven in the lineup that's not on sale.

The rail has no dedicated anti-rotation features; it depends entirely on the clamping force of the rail on barrel nut and proper nut torque on the upper. I think this is why Griffin specifies 55 ft-lbs for the barrel nut. I like how the nut doesn't need to be timed, takes a castle nut wrench, and Griffin includes a multi-use wrench plate with the rail.

Upon close observation, I noticed a bit of chatter on the barrel nut threads. You can feel some roughness screwing it onto unlubed upper threads. With enough moly grease, that feeling went away. The side of the rail has a set screw hole tapped after anodizing and looks like an afterthought (the coating bulges around the hole). This hole doesn't appear in any pics of the rail I've seen online. I'd guess this is a bit of insurance to keep the rail from sliding off the nut, which the design otherwise lacks.

What annoys me the most is Griffin's claim (https://www.griffinarmament.com/low-pro-m-lok-rail-12-5/) of 8.7 oz installed weight. I measured the total installed weight at 10.95 oz. I emailed them about this discrepancy and haven't heard back. Also, if you watch the install video (https://www.youtube.com/watch?v=d3L5f2zox80&t=135s) the owner doesn't grease the threads before installing the barrel nut, doesn't season the threads with 30 ft-lbs cycles, calls out the torque twice in in-lbs, and does the whole job with the rifle sitting in a magazine vise block. These kinds of details do not inspire confidence in Griffin as an AR builder.

[ViniVidivici]

Wow, that is a whole bunch of mess I would not expect of Griffin Armament. Wierd.

[Disciple]

What annoys me the most is Griffin's claim (https://www.griffinarmament.com/low-pro-m-lok-rail-12-5/) of 8.7 oz installed weight. I measured the total installed weight at 10.95 oz. I emailed them about this discrepancy and haven't heard back. Also, if you watch the install video (https://www.youtube.com/watch?v=d3L5f2zox80&t=135s) the owner doesn't grease the threads before installing the barrel nut, doesn't season the threads with 30 ft-lbs cycles, calls out the torque twice in in-lbs, and does the whole job with the rifle sitting in a magazine vise block. These kinds of details do not inspire confidence in Griffin as an AR builder.

Shit. Thanks for the heads-up.

[Sidneyious]

I like their buis and breaks, I'm in the milspec barrel nut gang.

I'm thinking of getting rid of this aero handguard on my 12.5 for another c4.

[Disciple]

I'm in the milspec barrel nut gang.

For compatibility, or because you believe they are superior?

[Disciple]

duplicate

[Disciple]

duplicate

[Sidneyious]

For compatibility, or because you believe they are superior?
Simplicity sake, I have a wrench that works for the barrel nut, castle nut and muzzle device all on one wrench I can get anywhere.

Almost every single gun owner has at least one of these wrenches.