Hokey religions and ancient lubricants are no match for a good Group IV PAO
Owner 360 Performance Shooting
Once upon a time I knew a fair bit about these things, and at that time Colt was the only one that did every single little thing "correct", if you believe the TDP to be "correct". BCM and a few others were very, very close.
The world has moved on, however, and now in the era of MOAR I see a *lot* of "better" being pushed. Much like a lot of things, I'm not completely sure what that "better" gets you, but there's a boatload of it if you really want it.
personally, I'd buy a Colt BCG or if you want something that's 99% of the Colt, get the BCM.
Got my upper. Now I need to, um, shoot it.
I just ordered a CCU from the local fun store. Now I just need to decide if I should put an ACOG on it or a Low Power Variable optic of some kind.
Anyone shot one of these (or any upper with the Centurion CMR Mlok rail) enough to comment on heat from the gas block? One reason I like having a rail with 45 degree slots is that it allows more protection from the gas block when using rail covers, but the CMR rail has large vent holes in that area.
I have a Colt Trooper which is similar except that it’s a carbine length has system with a government profile barrel. The rail is almost identical. I can tell you that it gets HOT in short order around the gas block. If you’re going to do anything faster than a shot every second or two, I recommend having gloves available. I’d be surprised if the CCU heats up any less.
My posts only represent my personal opinion and do not necessarily reflect the opinions or official policies of any employer, past or present. Obvious spelling errors are likely the result of an iPhone keyboard.
The Centurion MLOK rail is remarkably slim. It’s as close to the gas block as you can get.
Thanks, that's what I figured. I prefer shooting without gloves, but having to use one on the left hand may not be such a big deal
Yeah, they all get hot, but I can see some reasons why the CMR would be somewhat more problematic in this regard. As Jay points out, it's very slim, so runs quite close to the gas block. A quick look at the published internal diameter specs for popular MLOK rails seems to show the CMR is the slimmest (1.23"). Granted it's only a few hundredths of an inch smaller than the Geissele MK14 (1.27") and BCM MCMR (1.3"), but somewhat to significantly slimmer than the MK8 (1.35"), Noveske NSR (1.35"), ALG V3 (1.46"), or KAC URX 4 (1.53") and has those big honking vent holes right next to the gas block where rail covers won't help.
The CMR has a lot going for it, but no such thing as a free lunch. The simple answer is to wear gloves and drive on, I suppose.
Last edited by DiscipulusArmorum; 10-23-2018 at 11:42 PM.
One more reason that different isn’t always better. I changed to some of the slim handguards before Mlok or keymod were a thing and changed right back to a picatinny with Larue Index Clips wherever my hand rested and ladder bars where it didn’t. Still the best thing going for heat dissipation/insulation IMO.
I wish Daniel Defense still made the OG M4 handguard. Last time I checked they make a handguard that’s called M4 but it’s not actually the same. The OG M4 was the slimmest picatinny handguard I ever found.