BCM® RAIDER-M13 Rail




BCM® Standard 14.5" Mid Length Complete Upper Receiver Group w/ RAIDER-M13 Handguard

KeyMod version

Hmmm

That and KAC 3.1
I want one in 10.75

Interesting. It looks like the barrel nut is the same as before? I would like to see some testing on rigidity.

Nice! It's almost like the discontinued Bootleg PicLok and PicMod rails.

Yeah, it surprised me that they didn't try to elongate the barrel nut. Except for the mono- and pseudo-monolithic designs, most rails designed to be the most rigid have very long barrel nuts.

That is the weak link.  If you lengthen the barrel nut you gain leverage support.  I would be skeptical as well, but it is likely priced well above what I am willing to pay for a handguard anyway

Nice, how have I missed this? Might be the ticket to the RECCE build I’m working on.

I don't see the barrel nut as an issue, I had an MCMR rail on an upper I sold and it was excellent, besides there are other rails that clamp onto the mil-spec barrel nut and they get rave reviews.

Its more about the design of the mounting system on the rail, and BCM has a very good one.

I wish those we not discontinued. Very disappointed when I found that out.

Have you tested the MCMR rigidity against similar others? I have. The MCMR was designed to be lightweight, ergonomic, and modular, and it excels at those things. The friction and clamp attachment method is probably one of the best of the "slip fit" variety for general security. But as I predicted just by feel and intuition, it did the worst in my test for deflection. You have to take into account that some people will give a rave review if a rail attaches as designed and doesn't fall off or spin while being shot in static positions. Not many are actually attempting to measure the rigidity of rails in any way. I'm curious how this version fares.

I get the deflection issue, but I would imagine thats really more to do with the weight/thickness/strength/etc of the rail itself over its full length, not as much the length of the barrel nut.

From what I've experienced, the lighter the rail, the more likely to get deflection...hence the weight and rigidity of DD and Geissele. Even to a slightly lesser extent the ALG rails have a fairly shout body to them and have very little deflection.  Aero acheives this with their Enhanced rails with a larger diameter while using the BAR attachment (not the newer Atlas).

The older DD quad rails were stiff but heavy.

The evolution of free float rails has been interesting, if not frustrating at times for sure.

ETA... I think the Raider would likely be a stiffer rail in comparison to the MCMR due the the design, even with the same barrel nut and mounting hardware.  I hope to see a side by side look at this.

Agreed that weight/thickness/strength/etc are absolutely going to factor into it, but from the data available, it's not the whole story.

For example, a DD RIS III didn't do so great with flexing under a load, but is almost as good as monolithic systems in security and not being moved off position. That DD rail has a very short barrel nut and is bolted together in two parts. It does have an extremely robust attachment system though. I think these factors make sense with how it performed against loading. The Geissele Mk16 had the inverse strengths and weaknesses, and uses a longer barrel nut but more conventional mounting system.

The Aero Enhanced Gen 2 is exactly what I had in mind by "pseudo-monolithic." It has a large diameter and mounts directly to an upper. Despite being one of the cheapest in that test, it did pretty great.

I think the Raider is absolutely going to be stiffer than the MCMR, it was specifically made to be. How it will compare to others will be interesting. Since these deflection tests a new wave of designs has been released, such as SOLGW's M89 and L89 series with massive barrel nuts and a "wedging" mechanism that drives the rail into the upper receiver (another factor), as well as upper receivers cut to interlock with the rail. Cobalt Kinetics has taken a similar but more pseudo-mono approach.

It looks like a Geissele MK4.

Too little too late and still using their barrel nut lockup which is frankly annoying.

I might have forgotten to thank you for that comparison…if so, thanks.

I’d be pretty interested in one of these in a ~11”-11.5” length. BCM does do 12.5” barrels, so perhaps they have an interest in building a rail around one.

They may have decent customer service, but don’t think for a second they give a shit about what their customers want.

That most manufacturers don’t seem interested in supporting the footlong gang makes Baby Jesus weep. Or maybe there are too few of us to be worthwhile. It’s oddest when the same companies sell 12.5” Bbls, like BCM, DD, and G$. But they make rails specific to other barrel lengths, like 11.5”, 10.3”, 14.5”, etc. I guess they probably know roughly how many footlongs are out there vs the other lengths, and know that a lot of us will slap a shorter rail on there and move on.

Still, a guy can hope.

I hope too because 12.5 is my preferred barrel length, and BCM is the one who converted me! I get it, those other lengths are most common and govt issue, so it makes sense to support those lengths.

It’s not our fault the govt doesn’t know 12.5 is the best length for an AR!

Absolutely, hope you got something out of it and wish I had more rails at the time to test.

Someone else on the P&S discord did do a pretty thorough (though not 100% comprehensive) test on a good sample of popular/high-end rails. Personally, I'm considering the SOLGW Drive-Lock series first because of that. I'd love to know how the new Aero Mod 4 series does, and if they are going to make an 11.5ish" version.

This new BCM RAIDER seems more like a specific agency request made available to the public rather than a true successor to the MCMR.