Warning

 

Close

Confirm Action

Are you sure you wish to do this?

Confirm Cancel
PSA
Member Login

Site Notices
Posted: 11/22/2011 12:44:58 PM EDT
My FIL is wanting to find out some information regarding the AR15 he has in his basement.  This is on a pre-ban SGW lower.  He says it is a "Rhino System", and he has owned it since 1985.  



He says that the front screw of the piston system adjusts the cyclic rate.







What can the hive mind tell me about this??  Thanks....



-cvtrpr
Link Posted: 11/22/2011 1:45:06 PM EDT
Interesting. Do you have a pic of the carrier? Any signs of carrier tilt?
Link Posted: 11/22/2011 1:53:02 PM EDT
Last time I saw one was Dec 1991 at a fun show in Maryland. Selling price back in the day $80-$180. Looked neat, but who needs a piston in an AR 15. Added cost to the rifle meant less ammo or beer.

Hell, I was buying AR's at $400, Enfield's at $50 and HK 91's at $600. Rhino just was over priced and ahead of the times.
Link Posted: 11/22/2011 2:20:57 PM EDT
Looks cool... But it looks like you have to cut the handguards to fit the tube??
Link Posted: 11/22/2011 2:26:35 PM EDT
[Last Edit: 11/22/2011 2:28:41 PM EDT by RedFalconBill]
Link Posted: 11/22/2011 2:45:10 PM EDT
[Last Edit: 11/22/2011 2:47:34 PM EDT by MarkRSims]
Think I've got some detail pics on my laptop, I'll try and get them up later. I've been looking for one of these for a carbine for quite some time. They're rare.

Walt Langendorfer
Link Posted: 11/22/2011 3:04:13 PM EDT
Back in the 80's I got involved with Walt Langendorfer, the developer of the Rhino system.  I was helping him get the bugs out of the system with extensive testing.  Keep in mind that I was doing nothing but full auto firing, and I was hoping to get the Rhino system working to where you could use it for full auto firing and the chamber would not get so filthy.  The first problem I encountered was that the rod that pushes the bolt carrier rearward actually went into the Rhino bolt carrier key where there were some little buffers.  I had several of these carrier keys break.  After I was finished with working on the project, Walt told a friend of mine that the metal used in the manufacture of the original carrier keys had been inferior, so that problem was fixed with a new type of metal.  I don't know if that was true or not.  The next thing I had a problem with was that when firing full auto, the chamber did not foul, but the screw at the front of the FSB where the piston is would get stuck due to carbon buildup.  So, if you did not take that apart and clean it about every 400 rounds or so, you would not be able to get the piston area apart to clean it without some serious work.  The next problem was that the spring that is up there with the piston would collapse due to heat buildup, so they had to be replaced about every 500 rounds.  Again, I was doing full auto firing on these Rhino uppers.  I finally gave up on them and sold them off, but a friend of mine who purchased one of them said that on semi-auto, he did not have those kind of problems.  That is typical as full auto firing puts a lot of strain on parts that does not occur with semi-auto firing.  At any rate, the Rhino system was a good idea, but it just needed a little more development.  I think that the other piston systems that are available today or superior to the Rhino system, and parts for the Rhino system are no longer available.  If you want the Rhino system for "historical" puposes, that is fine.  If you plan on shooting it a lot, I would look at getting one of the newer piston systems if that is what you want.  I decided to stay away from the piston systems because that is not the way the M16 was designed to work.  Although other weapons using the piston system are really good, I did not have any problems with my M16 or AR15 using them with the gas impingement system, and even though I wanted a chamber that did not get dirty so fast, I decided to stay with the original design.  I don't do much full auto firing with the M16 now as ammo is much more expensive than it used to be.  Also, the full auto firing was fun but obviously not as accurate as firing semi-auto.  I would end up firing the M16 mostly in semi-auto mode for accuracy purposes, and in semi-auto firing, you do not build up carbon in the chamber that fast, so that is what I am staying with.  I spend most of my money now on suppressors and building different AR15 SBR's as I like the companct SBR's and like being able to shoot without having to wear hearing protection.

Charles Tatum
Link Posted: 11/22/2011 4:21:55 PM EDT
About 98% of the folks on AR15.com think that piston AR's are some new fangled technology..................
Link Posted: 11/22/2011 4:27:34 PM EDT
Rhino wasn't the first, either.  

Look up Colt R703.  

~Augee
Link Posted: 11/22/2011 6:58:37 PM EDT
Originally Posted By Engineer5:
About 98% of the folks on AR15.com think that piston AR's are some new fangled technology..................


Haha, it was new in 1969.

Link Posted: 11/22/2011 7:00:23 PM EDT
Originally Posted By Augee:
Rhino wasn't the first, either.  

Look up Colt R703.  

~Augee


+1  Talk about a rare bird...

Link Posted: 11/22/2011 7:21:20 PM EDT
Originally Posted By Morg308:
Originally Posted By Augee:
Rhino wasn't the first, either.  

Look up Colt R703.  

~Augee


+1  Talk about a rare bird...



Link Posted: 11/22/2011 7:25:08 PM EDT
[Last Edit: 11/22/2011 7:25:34 PM EDT by Augee]
Originally Posted By MarkRSims:
Originally Posted By Morg308:
Originally Posted By Augee:
Rhino wasn't the first, either.  

Look up Colt R703.  

~Augee


+1  Talk about a rare bird...



http://i295.photobucket.com/albums/mm155/markrsims/Rhino%20pictures/piston1xc0.jpg


Wait a second... where have I seen this before?  

A piston AR with odd sights and a non-standard upper height?  

You mean the HK416 was designed in 1969?!  

~Augee
Link Posted: 11/22/2011 7:36:10 PM EDT
[Last Edit: 11/22/2011 7:37:17 PM EDT by Morg308]
Actually looks like a Daewoo, which I understand are excellent weapons. What I don't understand is when we changed from thinking no one outside our country could have a good idea to thinking no one inside our country could have one. I personally think we have the talent to generate the best assault rifle of the 21st century right here, and I believe that US forces should be armed with US weapons. Period.

ETA: I don't mean FN's or HK's built in Georgia either dammit.
Link Posted: 11/22/2011 7:36:57 PM EDT
[Last Edit: 11/22/2011 7:42:20 PM EDT by MarkRSims]
Some of my Rhino pics:

ETA: Wish I had some pics of how the oprod interfaced with the carrier.
































Link Posted: 11/22/2011 7:38:25 PM EDT
Whew. Almost done. Now the techy stuff:












Link Posted: 11/22/2011 7:46:17 PM EDT
Last pic: The Rhino bolt doesn't have rings, because it doesn't need them.



Link Posted: 11/22/2011 8:00:53 PM EDT
OP your FIL has a nice treasure in the basement.
MarkRSims thanks for all the info. great reading material!
Link Posted: 11/23/2011 5:42:29 AM EDT
Mark,  

How does it shoot???
Link Posted: 11/23/2011 5:44:00 AM EDT
Originally Posted By MarkRSims:
Originally Posted By Morg308:
Originally Posted By Augee:
Rhino wasn't the first, either.  

Look up Colt R703.  

~Augee


+1  Talk about a rare bird...



http://i295.photobucket.com/albums/mm155/markrsims/Rhino%20pictures/piston1xc0.jpg


This would be a good project for JT !!!!  A 703 Clone.
Link Posted: 11/23/2011 6:04:09 AM EDT
[Last Edit: 11/23/2011 6:04:39 AM EDT by crackedcornish]
I picked up one complete Rhino system and one system missing the carrier key off of GB a couple of years ago for cheap $$

here's a pic of the later system that's modified so that they spaced the spring further away from the piston head to help deal with heat issues that the earlier systems were having on full auto...seems the heat from firing multiple long continuous bursts caused the springs to get hot and collapse or break

(the original GB pic)
Link Posted: 11/23/2011 6:13:12 AM EDT
Originally Posted By Dodge223:
Looks cool... But it looks like you have to cut the handguards to fit the tube??


yeah you do...probably why the one pictured by the OP has a set of Lone Star HG's on it
Link Posted: 11/23/2011 6:23:34 AM EDT
[Last Edit: 11/23/2011 6:31:00 AM EDT by crackedcornish]
Originally Posted By MarkRSims:
Some of my Rhino pics:

ETA: Wish I had some pics of how the oprod interfaced with the carrier.



Mark, the op rod fits into the key just like on the gas system guns, but the key is solid, and actually has a tiny buffer system (see fig 7) in it and uses a stud (part#43) in the gas hole of the carrier to take the pressure off of the screws so they don't break

this pic shows how it goes together
Link Posted: 11/24/2011 6:00:46 PM EDT
Originally Posted By Morg308:
I personally think we have the talent to generate the best assault rifle of the 21st century right here.


Talent, maybe. Experience, not really. The self-taught (largely) gun designer of the John M Browning, Carbine Williams, Stoner/Johnson/Sullivan mold is actively inhibited by today's regulatory environment.

BATFE may not want to kill the industry exactly, but they do want to consolidate it into a few large corporations.

Innovation is a function of the quality of minds working on a problem to the power of the quantity of minds working on the problem. While the people working for Colt, S&W, FNMI, HK, SIG, are high-quality engineers they are very few. They keep stealing old ideas from one another, because it's fairly mature technology, and so there are few really new ideas.

And remember, the last big revolution (the AR-15) came largely from amateurs in a tiny shop, coming in from another industry. Yes, Stoner and Johnson were pros, but they were not the whole team by any means. Meanwhile, the vast bureaucracy of DOD arsenals came up with the atrocious designed-by-committee SPIW, following their development of the M14 (a very mildly product-improved M1 that took them 21 years of struggle) and the M60 GPMG (which they "designed" by copying German guns, not even copying the feed tray mechanism right and unaware that the bolt and op rod they copied, the Germans had copied from the rather unreliable Lewis gun).

One thing that is working well right now is combat troop input into small arms design, especially from SOF to NSWG Crane and back out to the field, SOF first then everybody if SOF gives it thumbs up. But I think we're on the brink of another design by committee situation.  

Re: the Rhino

This was written up a lot in magazines at the time. I believe that Soldier of Fiction did an extensive test of it. I have about the first ten or twelve years of that magazine stored, but they aren't well organized at this time.
Link Posted: 11/24/2011 6:07:53 PM EDT
I saw this in Duncan Long's AR15 books maybe 10 years ago.
Link Posted: 11/25/2011 9:23:44 AM EDT
Cool stuff!  Looks like your FIL's rifle has the LSO handguards on it also! wish I could find a set of those
Link Posted: 11/25/2011 10:30:02 AM EDT
I've got a copy of that magazine somewhere. Now I HAVE to go find it!
Link Posted: 11/25/2011 11:04:17 AM EDT
My experience with the op-rod driven AR's is that they are not only less reliable, but many suffer from parts failures in low round-counts within the gun's early life.

As I'm seeing better reliability from well-built AR's than AK's in high-volume courses, the DI system still proves itself to be at least within the top 2 most reliable assault rifle operating systems to date.  AK's have plenty of issues when you actually start shooting them, and I've extensively used actual Russian, East German, Romanian, Yugoslavia, Polish, Finnish (the best hands down), Israeli (copy of Finnish), Bulgarian, Chinese, Egyptian, and even North Korean (the worst) variants of the Kalashnikov.  I'm not a big fan of the AK from a design, end-user, or practical perspective, although I maintain proficiency with them.

I became even more impressed with the long-term reliability record of the AR shooting them in -22C with bad winds, and seeing no malfs in a 2-day 800rd count per shooter course, where the guns are warmed up and cooled down constantly, versus being run warm the whole time.  That is a big hurdle for many guns to get over, and at least one of the AK's in that course couldn't take it.

The HK 416 has an atrocious handling quality to it that feels like a 20ga with slugs trying to tear the upper from the lower every time you pull the trigger, so I'm no fan of it either.  When you look at some of the main guys who have been instrumental bringing these op-rod systems to market, and then look at what they personally use during their carbine courses, you don't see them using the op-rod designs.  Take LAV and the HK 416, using DD DI AR's, or Magpul and the Masada now ACR using DI AR's, and that screams loudly to me which one is superior.
Link Posted: 11/26/2011 3:35:00 AM EDT
Originally Posted By LRRPF52:
My experience with the op-rod driven AR's is that they are not only less reliable, but many suffer from parts failures in low round-counts within the gun's early life.

As I'm seeing better reliability from well-built AR's than AK's in high-volume courses, the DI system still proves itself to be at least within the top 2 most reliable assault rifle operating systems to date.  AK's have plenty of issues when you actually start shooting them, and I've extensively used actual Russian, East German, Romanian, Yugoslavia, Polish, Finnish (the best hands down), Israeli (copy of Finnish), Bulgarian, Chinese, Egyptian, and even North Korean (the worst) variants of the Kalashnikov.  I'm not a big fan of the AK from a design, end-user, or practical perspective, although I maintain proficiency with them.

I became even more impressed with the long-term reliability record of the AR shooting them in -22C with bad winds, and seeing no malfs in a 2-day 800rd count per shooter course, where the guns are warmed up and cooled down constantly, versus being run warm the whole time.  That is a big hurdle for many guns to get over, and at least one of the AK's in that course couldn't take it.

The HK 416 has an atrocious handling quality to it that feels like a 20ga with slugs trying to tear the upper from the lower every time you pull the trigger, so I'm no fan of it either.  When you look at some of the main guys who have been instrumental bringing these op-rod systems to market, and then look at what they personally use during their carbine courses, you don't see them using the op-rod designs.  Take LAV and the HK 416, using DD DI AR's, or Magpul and the Masada now ACR using DI AR's, and that screams loudly to me which one is superior.


Interesting perspective and good read.

Link Posted: 11/26/2011 5:00:54 AM EDT
[Last Edit: 11/26/2011 12:03:24 PM EDT by Hognose]
Originally Posted By LRRPF52:
AK's have plenty of issues when you actually start shooting them, and I've extensively used actual Russian, East German, Romanian, Yugoslavia, Polish, Finnish (the best hands down), Israeli (copy of Finnish), Bulgarian, Chinese, Egyptian, and even North Korean (the worst) variants of the Kalashnikov.  


AK was designed to a different objective. There's a reason that the first click off safe in an AK is full-auto –– that's how Ivan and folks he's trained usually fire them. Their idea of realistic combat training is a lot different from ours.

In my unit in the 1980s we received a quantity of brand-new Romanian AKS-47s. We had enough for each man on a deployable SFOD to have an AK and/or M16A1. This was to give us a weapon that could be used in the event of UW operations in "the big one" and allow us to rearm by battlefield recovery and interdiction of enemy logistics. When we unpacked the AKs, first thing we noticed was that they had beautiful rust bluing and varnished forearms, with that strange donkey dong foregrip. (I still remember the serial number of "mine," and don't remember any M16s. Go figure). Next thing we noticed is that about one in twelve failed a function check. About another one in ten passed the function check but had some kind of chronic malf on the range.

We put it down to communist workmanship, the same idiocy that called Trabants and Moskvitchs "cars."

I do have a Finnish M62 and it is built like a Western arm.

AKs –– when you have one assembled before too many vodkas, and before they got too fat behind on the 5-year plan –– do seem to have higher tolerance for lots of auto fire, but you pay a price in accuracy. When you hear stories of M16 variants jamming, it's often in that rare situation where we have to fire a lot of full auto in a short period, like when 300 Taliban decide they want a 30-man COP in the Korengal.

[I became even more impressed with the long-term reliability record of the AR shooting them in -22C with bad winds, and seeing no malfs in a 2-day 800rd count per shooter course, where the guns are warmed up and cooled down constantly, versus being run warm the whole time.  That is a big hurdle for many guns to get over, and at least one of the AK's in that course couldn't take it.

The aerospace heritage of the AR pays dividends here. The processes and design of the AR is a lift from aircraft landing gear technology, actually. Your 7075 forging can go from ambient temp to the -60F at latitude and back and maintain its strength and dimensional stability, within the tolerances needed.

The 416 is typical german engineering, like a Porsche 911: a triumph of determined application of science over some questionable conceptual design. It works in the end because of sheer persisten Teutonic doggedness. Jars like the M27 though.

Edited: fixed typo.
Link Posted: 11/26/2011 5:59:24 AM EDT
Yeah, the Romanian variant AKM and AKMS are at the top of my turd list.  We ran them into deadline status just by shooting them during a spendex with 1st Group in 1998.  The AK's 100% reliability record is a perfect example of the effectiveness of a great propaganda campaign, which has more followers now in the US than probably all the former communist countries combined.

I actually spent some time training with Russian Cossacks in the winter of 2008-2009, and watched a lot of their videos from Chechnya and Dagestan.  Their SOF units even burn AKS-74's with RPK-74 mags on auto from the hip, and often carry the weapons with the stocks folded and in an other-than-ready position by professional Western SOF or Light Infantry standards.  I think they focus more on hand-to-hand than range time, except for one CT unit they have.

The newer Sako Rk95's are a nice gun, but suck to carry, like most billet receiver AK's, but it's accurate as all get out...1 MOA guns easy, especially with Lapua military ammo for the FDF.

Sorry for the thread hijack...
Top Top