While I wait to take pictures for an intro tread I thought I would chime in with my experience using this rail.
My complete rifle weighs exactly 7.0 lbs unloaded with a sling using a bathroom scale that measures up to .1 of a pound. It may seem as though I have a lot of crap on my weapon by first glance of the parts list but if you read further I have listed everything that would be relevant to changing the weight, which is everything primarily used. It's pretty much a bare rifle with a sling, iron sights, flash light, and MRDS optic.
The following are the relevant parts used: Stag blem lower, ALG ACT FCG (using the KNS pins and not the plated ones that came supplied), KNS 2nd gen anti walk pins, PSA LPK w/MOE pistol grip, Blackhawk/knoxx stock, milspec carbine buffer tube kit, Phase 5 BAD Lever, BCM complete upper (16" Middy LW CHF, A2 FH, KMR13, BCM BCG, BCM Mod 4 CH), Insight MRDS w/KZ mount, Magpul Pro F/R sights, Insight M6X flashlight/laser rifle kit (standard USGI pressure switch), Magpul standard attachment MS3 sling, Keymod QD rail mount (the one BCM sells), MI buffer tube sling mount (slide on type), (x2) BCM aluminum short rail sections, and two zip ties. I have a Harris Bipod but it isn't used on the rifle except for confirming zero.
This is if pretty great considering the standard Colt weights. Although, I'm not sure if these weights include a magazine and sights.
"Colt 6920 - 6.95 lbs
Colt 6921 - 6.8 lbs
Colt M4 - 6.8lbs
Colt Commando - 6.21 lbs
Colt 6721 - 7.3 lbs"
Originally posted by variablebinary (
https://www.m4carbine.net/showthread...carbines-weigh)
The rail feels great in hand, using the C-clamp extended arm front grip method. I tried using a Magpul AFG and a USGI vert. grip but I found that the rail is VERY comfortable just by itself. The problem for those who use this style of grip is that your hand ends up almost right where the gas block is on a mid-length gas system like mine. After zeroing the rifle's sights I fired 2 full magazines of Tula .223 in rapid succession with my hand at the fore mentioned location near the gas block and although the barrel was burning off the factory oil, my hand was just a little warm. I was wearing the standard black Mechanix gloves because it's a habit for me to wear gloves when I shoot. I will be purchasing the BCM covers for the gas block areas when they become available for future use in training.
As mentioned in one excellent Youtube video review, I believe it was "Twangandbang", the finish on the KMR rail is different than the standard anodizing/bluing of similar rails. It has a bit of texture to it I find (YMMV). I think BCM used this new coating because of the different metals used in the rail, correct me if I'm mistaken. We both conclude that this finish is cool but not extremely durable. The rail is susceptible to Knicks and scratches from adding and removing accessories from the top rail. I found that when Adding and removing the BCM keymod rails the finished was unharmed, but the same could not be said for the 3rd party Keymod QD mount they sell. When testing out different front mount locations I managed to kick up the keymod holes pretty good. This may have been due to over tightening on my part as I do not use a torque gauge for trivial things like that. This matters little to me as I view it as a tool and nothing more. I thought I would mention it regardless for those who would find this important. It should also be mentioned that you can mount a rail section to the 11 and 1 O'clock positions but you not be able to add accessories to that rail. There is simply no room.
In summary; I would absolutely buy this rail if you have the need for a long rail for the AR15. If you already have a similar tubular rail I personally wouldn't recommend buying this one to replace it. IMO there is little gained for the money and you could better utilize your funds on ammo and training. If you haven't purchased a rail yet or you are looking to replace your quad rail design hand guard I would say that this would be worth your while.
-Aldo
Bookmarks