I showed some pics before of my 1520 case that I throw all my Mk 18 kit in. The only thing I didn’t like about it was there wasn’t much space for mags. Got the idea to have some custom foam cut so I could fit mags. Just got it today and here’s how it turned out:



Holds:

- 6 rifle mags
- 3 pistol mags
- Otis 5.56/9mm cleaning kit
- Bottle of fireclean
- Spare batteries for EOTech, light and laser
- magnifier
- can

Upper, lower, pistol in holster and NODs w/ Crye Nightcap sit just neatly on top. Great little compact package that has just about everything I need.

Good job Tiny Crumb.

It's 13.2 and I had to leave that much much barrel for my suppressor to clear the rail :)

I don't so much care for the GL rail, but I do like the idea of cutting down my 14.5 to flush it up with my M4A1 RIS II rail.

Definitely need to shoot together. I have some even cooler shit in the works.

Thanks for the photos and info. I'm seriously considering sending my 14.5 SOCOM barrel off to ADCO now.

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Do it! It looks and handles so much better. Hopefully this will push you over the edge.

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Should I get in touch with a couple guys I know that work at Crane?

I don't think Crane would know honestly, I don't think the military ordered any besides maybe a few they might've tested. I think DD would be the most reliable word of mouth source, but dude said 100 and 1000, so maybe nobody knows.

good shit man.  what did you use to cut the foam?

I don't know if Crane would necessarily have all the info, its DD who really needs to spill the beans. But yeah, if someone at Crane could dig up the order we could at least know how many were ordered for that run.

 

Shitty part is either:
A- They are sitting in a Quad-con in some motor pool rotting away.
Or
B- They were already DRMO'd because they were seen as un needed.

Why is that G33 so gold? Mine was very flat tan.





Almost looks like the Airsoft ones I've seen. Did they change the process or coloring I wonder?













 

Is the KAC Micro 300M rear sight GTG?

It's an anno they used to do on them. Bronze/goldish anno with green rubber cover. Very hard to find.

Holy shit that's sweet.

No no, you can get them from China for $89 dollars, want a link?! Pretty sure I can even find you an Asian man to say "dis good quality, very high. Good as real ting, same assembly line".





Seriously though I've never seen one that looked like that. Damn China pirates musta gotten there mits on an early model!





 

Yeah, they don't show up very often and even less so for sale.

Then you haven't been paying attention.










The airsoft ones look like that because they're trying to copy the ones SOCOM has.

They're tough to track down but the newer flat FDE ones just look wrong.

I didn't cut it myself. Just measured everything out and sent it off. There's tons of companies online that will do custom foam inserts, they just have to know what size case you have and the measured cuts you want. The biggest reason I didn't do it myself is because everything is a different depth. For instance the fireclean and silencer spot are only .5" deep, the mags are a custom depth to fit 2 stacked, the cleaning kit is 2" deep, all the way through, batteries are custom depth so that they just come to the surface, etc… The magnifier has 2 different depths in the same slot to account for the QD attachment that sticks out farther. I would have tried to just use a foam cutter myself but there was no way I could get a nice detailed 3d result with that unless I did something hacky like stacking multiple layers of .25" foam or something.

The original RIS II program was conceived of as a 7" FF carbine rail.  

Ostensibly, the carbine rail would have been used for both the CQBR and the M4A1 and retain the fixed FSB.  

Remember that the Block II program also consisted of a "BIS II" component (Back-up Iron Sight) - notably, they did not request a front sight for the BIS II, only a rear - if they had initially "intended" to use a front flip up sight, they almost certainly would have requested a front sight component be a part of the "BIS II."  

Both ARMS and KAC submitted both RIS II and BIS II designs.  The BIS II was dropped pretty quickly, as the MATECH was being supplied with factory M4A1s at that point anyways.  

DD was the only company to deviate from the 7" rail, and submitted an "MRE-esque" design as their RIS II submission, based on the LITE rail.  

The 12" RIS II was originally designed for the M16A4 with the fixed FSP.  

Their extended M4A1 rail also necessitated the design of a rail compatible with the CQBR.  

I'm not sure who exactly came up with the idea first or at what stage in the development - but one way or another, it was quickly realized that removing and reinstalling the FSB to facilitate the mounting of the M4A1 RIS II was far more difficult and complicated than simply removing the existing FSB and then installing the M16A4 RIS II.  In order to facilitate this - the gas block and front sight of the MK 12 MOD 1, which was already available (as well as its small parts) were re-appropriated.  And since all things "Block II" were supposed to be "tan" - KAC was asked to make some MK 12 front sights in tan.  

I am not sure whether this was before or after the "MK18" RIS II was developed - however, whatever sequence the development occurred in - other than perhaps a few test and evaluation examples, the Block II CQBR assemblies were the first configuration fielded in significant number, in the non-FSB version.  

After that, for a long while, the non-FSP M4A1 rail was fielded almost exclusively, except for a small number of examples - but this is/was more a function of the organizations that ordered them, and what they asked for.  

The fact that the non-FSP M4A1 rail was originally designed for the M16A4 is the reason that the 14.5" has so much "extra" barrel exposed compared to the "MK18" and GL/SSC variants - it fits the M16A4 perfectly:

Prototype:




Production:




To that end, the "FSP" variants were not, as far as I can tell - in any way a "stop gap" measure.  

If I were to guess, whomever asked for the MK18 FSP RIS II probably ordered a very small number, then decided they were too much of a pain in the ass, and are using the much easier to install non-FSP version.  

With that being said - my inclination would be that they probably ordered... say, 1,000 of them, DD started cranking them out - got the first couple initial low rate production examples, and then decided to change their "order" to non-FSP variants.  At which point, DD was left "holding" the ones that they'd already produced that were basically worthless.  

My guess is that there are probably more in civilian hands than there are in the military... probably under a hundred gathering dust from the initial delivery.  The rest went to BCM, Rainier, etc. and got sold off slowly, some at rock bottom prices, until the majority were snapped up by deal hunters looking, rather than by "cloners" until they were gone for good - most of whom will probably never grace this thread and have any idea that the cheap DD rail they picked up is so "sought after" and "highly coveted."  

I wouldn't speculate on how many there are "actually" out there, but I suspect that the number is higher than many think.  

Another thing to consider is that pre-eForms, the CQBR thread moved a lot slower than the M4A1 thread, a trend that's been reversed for quite a while now.  



Re: the 10.3" barrel length of the CQBR - it's really quite arbitrary and simple -

10.3" (or 10.25", depending on whom you ask) is the shortest length that the barrel can be without removing the bayonet lug, and still mount an M4QDSS.  Part of the reason that many manufacturers went with 10.5", besides being a more "round" number, is that some suppressor required more clearance, and the extra .2" allowed for additional compatibility.  Incidentally, the "MK18" RIS II was similarly designed to be as long as it could be while using the same barrel length and suppressor combination.  Essentially, the whole length of the barrel and RIS II is based on the folks at NSWC-Crane not wanting to do a single machining operation to remove the bayonet lug.  At this point, however - the Block II CQBR no longer uses an FSB at all, so not removing the bayonet lug is irrelevant - and the M4QDSS is beginning to be replaced with the SOCOM-RC - meaning that kind of like the old cliche about roads being the width of horses' asses, the length of the CQBR has become completely arbitrary as the conditions that the dimensions were originally based on are no longer relevant.  

~Augee

Augmented with knowledge by Augee.
My day is now complete
Thank you,

Snagging my M4 RIS FSP today, then sending it off to Stoner (the man) for a snip snip.

ETA for new page


And can we get a major MK18 FSP pic dump?  Just got the rail and Stoner and I want as many pics as possible to figure out where the best places for cuts are.
Also - just threw a 99051 on the EE, I'll knock a few bucks off for people in this thread.
Cerakote color combos I'm looking at are patriot brown, burnt bronze, and armor black.  Probably 8 parts patriot brown, 1 part armor black, 1 part burnt bronze.

You guys keep quoting 12.5" barrels for GL/SCC but note on DD's poster it says 12.25"

       Fyi, I'm chasing a unicorn so I have to unload some parts. I just put a DD Mil contract overrun barrel/gas block on EE.
 

Howdy, all!

I've been lurking for a few weeks, and this thread and the Mk12 thread have inspired me to clone a couple of rifles.  These recent posts with those short FSP RIS II rails have been making me especially moist in my nether regions.  Considering the M4A1 rails are on sale at Brownells now:

http://www.brownells.com/rifle-parts/forend-amp-handguard-parts/handguards-amp-rails/ar-15-m16-ris-ii-m4a1-fsp-handguard-prod81785.aspx

I guess I'm going to have to do my own chop job on one...

I'm on that as well.  Check pages 1037 and 1056 (I think) for more info.

If you guys need any more info regarding the chop job, let me know.

Thanks!  I just bookmarked those pages for future reference.

Pimpin' ain't easy?

Non-Referal Link-$199.99

Use code: L3B for $15 off, or add something super cheap and use L3C for $25 off $200.

The real question is will these stay at this price or drop to a really low one like before?

Odd thing I notice is they say they are "discontinued" under where you would click add to cart

Hmm......

If Brownells runs out again and any of you guys miss them, I got a couple spares. Not looking to make anything off them or anything.
 

Crane specs say they cut the barrels to 12.30" +/- with a .60" long thread. This seems puts the shoulder before the threads under the rail. I believe they were cut this length to avoid having the flare at the end of the barrel after the M203 cutout. If my measurements are correct, a 12.59" barrel with a .63" long thread would put the shoulder before the threads right at the end of the rail.

If no one buys them for $199 they will drop.

 

The big question is how does this keep happening. Is Brownell's spacing out sales of their inventory, does DD keep supplying them periodically?

This is sort of what was posted about the 10.3 barrels......spec says 10.25", everyone agrees on 10.3". I'm betting the tolerance is +/- .1 or maybe more

I'm betting the former. The black ones are not as sought after, so Brownells has likely beeen sitting on stock for a good while. I'm sure they aren't losing $$ on the deal

They only have 8 left in stock right now...they'll sell out at this price.

Added two bottles of FireClean to my order to use the $25 off code.

Paging Stoner...

Oh damn!

Anyone know where to get a good deal on an LMT 10.5 upper?  Don't need handguard/rail, BCG, CH, or any of that jazz.

Postman just paid me a visit:



Now just need a barrel, BCG and rail chop to finish this newest "Mk18 RIS II FSP" upper.

Niiiiiiiiice    ...what are you planning on doing with the second 4P?

Still undecided on the second one.

My second will be pinned to a 14.5" FSP Block II clone! ...I know, sacrilege!

12.30" is to the middle of the spec. The tolerance to where the cut is measured from has a -.010 tolerance and the cut dimension has a +.020 tolerance so it isn't nearly that much. FWIW, Crane spec on the 10.3" barrels is 10.35" +/-.