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1/25/2018 7:38:29 AM
Posted: 10/19/2002 6:40:08 AM EST
I just wrote and posted an article about this thing on Defense Review(www.defensereview.com). It's a drop-in upper for any AR-15/CAR-15 that negates felt-recoil and muzzle climb, and runs much cleaner and more reliably than a standard AR/CAR upper.

Here's the direct link to the full story on DefRev:


I hope you guys enjoy it.
Link Posted: 10/19/2002 6:53:48 AM EST
[Last Edit: 10/19/2002 11:11:24 AM EST by Kaliburz]
I just glanced at the story, but I looked at the PDF file.

But, one question. Do you happen to have any pictures? Had to ask...

Edit, if I understand, it is similar to the upper unit that was on a Daewoo? ....$1500 yikes...

I missed that issue (Jan. 2003 issue of GWLE).... gonna have to go find it.

Link Posted: 10/19/2002 6:57:44 AM EST
Where can we see a picture of this bad boy upper?

Nice article BTW and yes, you've peaked my interest.

Link Posted: 10/19/2002 10:06:35 AM EST
[Last Edit: 10/19/2002 10:07:47 AM EST by DevL]
I read the GWLE article yesterday and while I was interested when I started reading I wasnt by the time I finished the article. It is far too complex and uses a hydrolic buffer (colt did that before and they leaked) It weights a pound more than a HEAVY BARREL AR15. Yikes that is too much weight. The reciever is NP3 coated and there is no anodization... Dumb choice as hard anodization is the best choice for an aluminum finish. The steel parts have a "super secret voodoo finish" that cant be etched with a diamond cutter? Sounds fishy to me.

It allows full auto to be used at ranges of up to 200 yards. But it also weighs 2 lbs more than an M4A1. Everyone knows increasing the weight of a rifle and adding a brake/compensator will do this. There is already a company that does a drop in upper for the AR15 that is piston driven. Its called the ZM Weapons upper. This system looks a bit more like an M16/AR15 upper than the ZM unit but the fact is you still need an ENTIRE new upper and the ZM Weapons rifle still only weighs 7 pounds. Granted the ZM unit fires too fast on full auto but this concept is nothing new.

I will stick with the basic M4 design and I am sure the military wont be adopting the system any time in the near future.

Link Posted: 10/19/2002 11:35:49 AM EST
[Last Edit: 10/19/2002 11:38:41 AM EST by DBLTAP]

You make some good points... I was reading it and was impressed myself but I forgot totally about the ZM weapon system...

I was mostly impressed that the weapon did not get dirty... ANYONE WITH A ZM UPPER HERE?? DOES IT GET DIRTY? I have never had the chance to shoot/ see a ZM unit.

I don’t like the idea of the hydraulic buffer either or the weight of the thing... all the weight looks to be in the heat sink/ barrel sleeve and hand guard.

It definitely looks/ sounds interesting though…
Link Posted: 10/20/2002 10:51:02 AM EST
[Last Edit: 10/20/2002 10:55:28 AM EST by DavidCrane]

I won't argue with you about the weight or complexity problems. However, the ZM Weapons LR-300ML has problems on full auto. Because of its design(modified gas/op rod system), the springs will heat up, lose their temper, and eventually fail.

As I understand it, the recoil spring is wrapped around the op-rod(I've actually forgotten exactly what my source told me.). Anyway, I know the spring is wrapped around something it shouldn't be. Because of this, according to several of my sources, the LR-300ML simply cannot handle being run extensively on full-auto. If you are going to bring up another weapon system, you would be better served by talking about M2 Corporation's M16SP, M16-C, and M16SP-2. Of course, these weapons don't address the recoil issue, but they do seem to solve the reliability and overheat problems with regards to extensive full-auto fire. They are currently in use with several elite military units because of this.


Link Posted: 10/20/2002 10:53:53 AM EST
By the way, DevL, I'm sorry the article bored you. Frankly, I'd rather be wrong or off about something than boring. "Wrong" I can always correct.

Hopefully there's something else on my site you will like.


Link Posted: 10/20/2002 3:53:28 PM EST
I didnt read your article till after I posted. I had read the GWLA article. I am uninterested in the weapon system but have nothing bad to say about you or your article. In many ways it was better than the GWLE article. The voodoo rifle finish ended up being a teflon impregnated in parkerizing type finish after reading the link you posted. You quoted the manufacturer as to what they said about the finish and you didnt make it sound like the "new finish of the 21st century" like GWLE did. Little things like that make me lose interst quickly. Your article was beter researched and more objective. Although it was similiar to the GWLE article I liked it more. I find much I like at your site and hope you dont think I am knocking you because I am not.
Link Posted: 10/20/2002 7:39:09 PM EST
[Last Edit: 10/20/2002 7:40:48 PM EST by DavidCrane]

Thank you for the kind words. It actually means a lot to me that you preferred my piece. I've sort of had to learn that lesson(about remaining as objective as possible) as I go along. I myself have been guilty of buying into the whiz-bang nature of new products before, only later to find out that I shouldn't have been so gung-ho about them. You saying what you just did is informative for me, and reinforces the importance of keeping an objective eye, particularly when something is unproven.

DefRev(DefenseReview.com) takes a lot of work, but I think it's worth it if people enjoy it. Building the membership has been a pain in the butt, in that it's been a slow process, but at least they're consistently tricklin' in. :-)
Link Posted: 10/23/2002 1:04:12 PM EST
I beleive this is the same upper in question here . (i was to lazy to read all the posts) But Guns & Weapons does a nice piece on it in the Jan 2003 magazine. Here's a link you can see the sweet thing on the cover .

Anyone know where or when we can gettem ?

Good shooting
Link Posted: 10/24/2002 11:50:03 PM EST
[Last Edit: 10/24/2002 11:51:13 PM EST by sopmodm4]
I remember those little Rhino piston conversion kits they had back in the 1980's and they were the beans if you had the screws that held it to the bolt carrier staked properly.They only cost $89 if I remember correctly and they gave you an AK style gas piston,FN style gas adjustment and added to the operating mass of the reciprocating parts slowing the cyclic rate just a wee bit.

$1500 vs. $89?

I wish they would bring that Rhino System back to the market.I'd buy another one right now.
Link Posted: 10/25/2002 3:07:25 AM EST
[Last Edit: 10/25/2002 3:08:37 AM EST by TacCar]
I like the concept. Improving reliability is always a plus. If I were to go this way, what with all the crap I'm already planning on hanging on my AR, with this conversion I'd be lugging around one fat Carbine. Another thing that strikes me is if your gonna embark on manufacturing a setup like this, you might want to make it more compatible with say a A.R.M.s SIR or KAC RAS2 freefloat rig. I think most AR users(civilians anyways) will probably go with one of these if they are in fact contemplating a freefloat setup. maybe KAC or A.R.M.s will come up with a gas system/freefloat forearm combo(dreaming). Damnit!, as soon as I think I've settled on the final, ultimate, this time I really mean it configuration for my AR, I come across something like this and start to question my choices and start wondering about going another direction altogether.

BTW, does anybody know who makes the front sight pictured on the rifle on the cover of GWLE?
Link Posted: 10/25/2002 3:22:41 AM EST
The RROC comes with a railed FF tube on it. As far as reliability is concerned I dont think it will prove to be more reliable in the long term. The buffer will end up leaking, people will forget to clean the gas tube/operating rod area because the AR does not need its gas tube cleaned. The AR gas system is ONLY less reliable in that it cant fire full auto that long because it does not weigh 9 lbs with a mammoth heak sink on it and it needs to be cleaned every 1000 rounds or so. I like my rifle light and I clean it, so reliability is not an issue for me. As a civilian I cant own a fullauto without a lot of $ and hassle. I think its a solution to a problem that does not exist. Kind of like the .357 Sig.

Full auto is best used at close range against multiple targets. In that situation I WANT a fast cyclic rate to put out as much firepower as fast as possible.

I thought I might be going in the wrong direction in my M4 build up when I started reading the article. By the time I was finished and thought about it I wouldnt want one if it cost the SAME as a regualr AR15.
Link Posted: 11/1/2002 10:30:08 PM EST
My biggest complaint w/ the RROC is its heft, relative to most carbines. I find it difficult to understand why C. Cutshaw didn't attribute at least some of the recoil buffering of the design to its increased weight - mass does dampen felt recoil.

It would've been nice if the design could be used w/ the SIR, which would drop the weight a little (the SIR bottom section being polymer instead of the RROC's all-metal tube). Also, the hydraulic buffer could be potentially problematic. As well, a PRI front folder won't work with it - bummer.
Link Posted: 11/1/2002 11:56:59 PM EST
Looks like the handguard is made of Carbon Fiber with full length aluminum 1913 std rail on top, and three other bolted to the carbon fiber handguard at the 3, 6, and 9 o'clock position. The top rail is bonded, or bolted to the carbon fiber somehow.

Just my observation.
Link Posted: 11/2/2002 10:09:39 AM EST

Originally Posted By SMGLee:
Looks like the handguard is made of Carbon Fiber with full length aluminum 1913 std rail on top, and three other bolted to the carbon fiber handguard at the 3, 6, and 9 o'clock position. The top rail is bonded, or bolted to the carbon fiber somehow.

Just my observation.

Per the article (I have it in front of me now), the tube is machined, though an extrusion is likely for production units.


I am beginning to think that an improved version of the Rhino systm would have been a simpler, cheaper alternative. A full replacement bolt incorporating an op rod, rather than attaching it to the existing bolt with screws (the only flaw w/ the original Rhino), would've been possible.

Between the hydraulic buffer (How robust is it?) and other specialized parts, and the excess weight, it's still an unknown quantity.


Make it lighter, & make it compatible for use with other mounting systems, sights, etc. As well, demonstrate that the design's specialized, individual parts will hold up (e.g. hydraulic buffer) to FA/other abuse.
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