Cheese Graters 2021

[kyjd75]

I have a couple of Centurion Arms rifles, one is 11.5 with a 10" C4 quad rail, and the other is a 14.5 with a 12" C4 quad rail. I really like these rails. Very solid, very stout, and very well finished. No mistaking the quality of these rails. If I'm buying another CA upper, I'm probably going to go with another C4 quad rail, even though CA offers a plethora of rail choices.

[titsonritz]

I have a DD RIS II FSP and an Omega 9.0 and a Geissele MK4 hybrid. I do like pic rails and have been thinking of picking up a Geissele MK7. I have a couple Centurion rails but they are both M-Lok.

[Firefly]

I really, really like the Larue for its "Short" bottom rail and "Skinny" profile. Put a Knight panel on the bottom with ergo ladders on the sides and it feels good, with thermal protection when you get to shooting a bunch of magazines (not the proverbial "Mag dump," but shooting lots of targets). Con going against it is spotty availability during covid craziness.

The Daniel Defense Omega free-float drop-in is a good choice if it's an issue gun and you're not allowed to modify the base weapon (i.e., driving out the sight base pins and replacing the barrel nut and delta ring assembly) under threat of military non-judicial punishment.

If it's your gun and you are required (by unit or department policy) to keep quad-rails then I'd try a BCM QRF. I bought one last month for a full-length M16A4 equivalent for $150 from Primary Arms. It's a little "Fatter" than the Larue but not objectionably so. The SLR Rifleworks and Midwest Industries options are good-to-go as well.

I must admit that between the KAC and Larue free float quads, the Larue was superior. That’s what I made that one LMT upper with. If I seriously had to pick, it would be admittedly Larue

[gunnerblue]

I really, really like the Larue for its "Short" bottom rail and "Skinny" profile. Put a Knight panel on the bottom with ergo ladders on the sides and it feels good, with thermal protection when you get to shooting a bunch of magazines (not the proverbial "Mag dump," but shooting lots of targets). Con going against it is spotty availability during covid craziness.

The Daniel Defense Omega free-float drop-in is a good choice if it's an issue gun and you're not allowed to modify the base weapon (i.e., driving out the sight base pins and replacing the barrel nut and delta ring assembly) under threat of military non-judicial punishment.

If it's your gun and you are required (by unit or department policy) to keep quad-rails then I'd try a BCM QRF. I bought one last month for a full-length M16A4 equivalent for $150 from Primary Arms. It's a little "Fatter" than the Larue but not objectionably so. The SLR Rifleworks and Midwest Industries options are good-to-go as well.

Exactly why I went with the Omega in 7" length. I'm curious, since it mounts on a GI barrel nut,, how much flex would longer lengths have? Considering that the GI nut arrangement called for attachment points on both ends of the handguard. I suppose the same question could be applied to the C4 rails.

[sinister]

I have a DD 12.0 Omega on a flat-top 1-7 M16A1-profile barreled rifle and so far it's great. I didn't drive the pins out of the front sight triangle.

Granted I don't do fire-and-maneuver or parachute landing falls on it, so there's that.

[1168]

Thanks for the input so far. It looks like BCM is the most appealing. Like a DD RIS II in feel, which seems to have aged well, but a little lighter.

[17K]

I like the QRF for the weight but the install is an absolute mess with having to heat the rail to slip over the nut.

The short barrel nut and little screws are a weak design that’s made to work by using an interference fit between the barrel nut and rail.

I think I would go with a Centurion C4 due to it’s more civilized method of install.

[1168]

I like the QRF for the weight but the install is an absolute mess with having to heat the rail to slip over the nut.

The short barrel nut and little screws are a weak design that’s made to work by using an interference fit between the barrel nut and rail.

Thats a good point that I did not consider. DD’s method seems similarly sub-optimal in the barrel nut, as well. Does the QRF take a beating and hold zero? Does it flex excessively when side loaded, like with a sling?

[17K]

Thats a good point that I did not consider. DD’s method seems similarly sub-optimal in the barrel nut, as well. Does the QRF take a beating and hold zero? Does it flex excessively when side loaded, like with a sling?

The DD bolt up is more like a unión that pulls on the back face of the barrel nut, the BCM is just like a muffler or hose clamp.

The rail itself is extremely stout because it’s a tube with the rails on it. The only thing that would really knock a zero off would be if it took a hard enough hit to make it squirm on the rail.

[1168]

The DD bolt up is more like a unión that pulls on the back face of the barrel nut, the BCM is just like a muffler or hose clamp.

The rail itself is extremely stout because it’s a tube with the rails on it. The only thing that would really knock a zero off would be if it took a hard enough hit to make it squirm on the rail.

And in your opinion, a hit sufficiently hard to squirm the rail on the nut would be hard enough that you would consider it GTG with a PEQ?

I just discovered that the URX3 is still available. Anybody using one with full pic rail panels? How’s it feel/weigh? I missed out on that gen of KAC rails.

I’ll google around for more BCM reviews later, about to go shoot.