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Posted: 3/17/2010 5:47:11 PM EST
Like the title says, I got home from work today and it was like Christmas.  2K rounds of projectiles to load up, my new Sightron Big Sky 1.5-5X20 scope and, of course, the piston system.  I also have a pencil barrel coming in, but just couldn't wait to install the piston; so, I just installed it on a Carbine that I have with an M4 profile barrel.  The install went smoothly, but things didn't just slide right in like the instructions suggest they should.  Getting the op rod in after having installed the piston took a bit of coaxing, but I got it all installed none the less.  In hind sight, it would have been easier to loosen up the gas block and do the install, but my gas block is red loctited on and I wouldn't have wanted to fool with that anyway.

After having gotten the kit install, I did the usual check to make sure that there was no binding, I cut the heat shields in my MOE handguards, installed the handguards, cleaned some excess grease from around the delta ring area (from a recent barrel install) and....binding.  I was like "what the heck?"  I checked through everything and it turned out that when I was cleaning the grease from around the delta ring area, I had nudged the ring clamp over a bit and that caused the binding, so I got in there with a small screw driver and re-centered the clamp.  I played around with it abit and all seemed well.  I cleaned my mess up and picked the carbine up again to play with it some more.  I locked the bolt back and see-sawed the carbine to listen to the click-click of the rod moving back and forth.  Well, no click-click.  I checked it all again.  It appears that while I was messing with it, I had nudged the delta ring itself and it was causing the rod to bind.  I re-centered the delta ring and all was well.

According to the posts that I've seen, the piston system is not very tolerant of any sort of binding.  I have to wonder if either one of the situations described above would have caused the weapon to malfunction.  I'm going to take it out Saturday and give the delta ring a little twist and see if it turns the carbine into a single shot.  If it does, I'm going to have to improvise something that holds the D-ring and ring clamp stationary.   On the other hand, I may just have an Osprey for sale cheap Saturday night.
Link Posted: 3/18/2010 11:47:42 AM EST
I have the rifle kit installed in my 20" A2 with the factory handguards and delta ring setup. I can get it to bind up if I twist it hard enough but it did'nt stop it from functioning.
Link Posted: 3/18/2010 2:16:53 PM EST
will this occur with other install kits as well?
Link Posted: 3/18/2010 8:07:54 PM EST
Its not gonna stop it from working as theres a good amount of force from the gas pushing that rod.I have 2 systems and im buying my 3rd next week...I wouldnt be going on 3 if it didnt work.Ive taken a couple of classes with my first carbine to get the kit and im sure during the class I twisted and turned the gaurds along with bumping the rifle into things and it ran without a hitch.
Link Posted: 3/18/2010 8:55:27 PM EST
Thanks for the info.  I feel a lot better about it.  I have another problem now.  I put a pencil barrel on the carbine with the Osprey kit on it and when I was installing the chamber on the FSB, the chamber came off of the tube.  Corey at Osprey did tell me that they are two pieces and are designed to "self adjust," but now when I raise the muzzle, the chamber slides off of the tube in the FSB.

I emailed Corey, hopefully it's going to be something simple like putting loctite on the tube or something.
Link Posted: 3/19/2010 1:02:46 AM EST

Never heard of this,it looks like one piece to me. Pics??
Link Posted: 3/19/2010 3:55:42 AM EST
I'll try to post pics later.  I just got an email from Cory and yes, they are two pieces.  The tube and the chamber, but he said that it should not have come apart.  He's sending me another chamber and piston.

Now I just have to figure out how to get this bushing out of the upper.  I reallly want to shoot this rifle.
Link Posted: 3/19/2010 5:28:14 PM EST
Yes they are pressure fit Corey says its 3x stronger than the original and its made to adjust by itself to the FSB because of variances.I had the same problem although it still functioned..its my #2 kit and like wise I have a new chamber coming...everything has teething problems and the support from Cory and Osprey is out standing.I sent the parts back to him so it can be looked at..but no worry they will take care of it.So yes now its 2 pieces the gas cyclinder and the spigot.Its made that so as it adjusts and moves toward the FSB it gets tighter.In any event im buying my 3rd system next week..I love the simplicity and reliability and the support from Osprey.

Hell I remember when it used to be lietner and wise my brother got one of those and it had its fair share of teething problems wich is why they stopped conversions.I belive the osprey is the simplest and most reliable conversion.All I can say is that even though the chamber came loose from the spigot it kept working as I ran 400 rds through it last weekend..so I dont know when it happened but it still rtan without a hitch and that says alot about the systems robustness.Tolerances are real tight so its not noticable that its 2 pieces.Not all front sight bases are the same so its good that the cyclinder self adjusts to the FSB.
Link Posted: 3/19/2010 8:34:04 PM EST
I tried to snap some pics, but after is came apart, I could see that it was just friction fitted, so I put some red loctite on the spicket and racked the bolt a couple of times.  It has about 1/32" play in it and seems to be solid and I couldn't get it back apart.  I'm going to shoot it tomorrow and see how it goes.
Link Posted: 3/19/2010 9:31:59 PM EST
I cant wait to see how it functions.This will be a great test as mine still functioned even when loose..yours will be like the field expedient fix test,Im betting its gonna work just fineif this works id like to see other piston systems be put back into service quicker..I doubt it and goes to show why simpler is better.Even with a part failure in a critical area the system kept functioning...that speaks volumes.Im glad in a way it did happen it just goes to show how robust the Osprey design is.I love this systemand the fact that the loc tite or even epoxy will get it back in the game means that for cement heads like myself it cant get easier..the AK of piston systems if you will
Link Posted: 3/20/2010 9:36:08 AM EST
OK, it just got back from the range.  As I said, I used red loctite to put the parts back together again.  And now, 630 rounds of Silver Bear later, what can I say?  It ran from the first magazine I slapped into it.  It does leak some gas under the handguard, but just a bit more than my gas tube did.  Almost not even worth mentioning.  I can't make any comments on how it performed except to say that it worked....flawlessly.  My problem now is that Corey is going to want the "broken" parts back, and now you couldn't tell that anything was wrong.  Once I fired 100 rounds and everything sealed up, I can't even twist the chamber on the spicket.  What am I going to do?  Corey is going to think that I was lying.

Now, I'm going to sound like a broken record.  When I got home, I cracked the receiver and decided that I'll clean it after the next time I go shooting.  The receiver is still clean and wet.

I've gotta say, the simplicity of the system is its strong point.  Even when something does go wrong, it can't be much of a worry.  All of the parts are rigid and the system is surprisingly smooth.  And get this, I realized that the piston is binding in the hole for the gas tube in my MOE handguards.  I realized this AFTER  I put 630 rounds through it.

I've heard comments from a bunch of guys, naysayers if you will, who make the common comment of, "you don't need a piston kit, go buy a cleaning kit."  All I can say is that they don't know what they're talking about.  They must never have tried a system like this out before.  Me, I'm just rejoicing in the fact that I'll never have to buy another carbon killer to get the carbon off of my bolt.   I'm gonna get one of these piston systems for each of my other two ARs.
Link Posted: 3/20/2010 1:08:01 PM EST
Sorry, wrong thread.
Link Posted: 3/20/2010 3:31:55 PM EST
Its a bitch to push the pin out but if you use a center punch that pin thats holding the cyclinder in will come out and then its easy to remove.Glad to hear everything functioned 100% after the field fix.I doubt any other system could have functioned after a failure like that but Osprey didI dont think you will be looked at like a liar as the same happened to me and the parts are on the way back so they will be able to see what went wrong.Im ordering kit#3 on monday..3 down and 1 to goin my book at least for me DI operation is dead.

Doesnt matter what the naysayers say the facts are the Army wants interim upgrades to be done to the M4 and to be done on all rifles in inventory by 2013..so like it or not the DI purists will get dragged kicking and screaming to the new spec.All bet once the Army picks a system and starts the upgrade these same people will want what the Army and marines are using.Hell with the new requirements to upgrade the M4 the Marines could do the same changes with Ospreys system for the full-size rifle..Ospreys going places gents
Link Posted: 3/20/2010 7:05:01 PM EST
I was thinking the same thing about the M4 upgrades, because if you think about it and assume all things to be equal (in terms of performance) among the different brands of piston systems, the Osprey will be a drop in on all of the weapons to be upgraded.  No gas block swaps or anything.  For all practical purposes, all that has to be replaced is the gas tube and bolt with no small parts or springs to worry about, except the clip that hold the op rod to the piston and to tell the truth, I could improvise one of those PDQ.  Since it's load is not lateral in anyway, I'll be that nail and duct tape would serve in a pinch.
Link Posted: 3/20/2010 9:20:59 PM EST
I like the way you think bro...improvise,adapt overcomeand its easy to follow with an obviously indestructible system.
Link Posted: 3/22/2010 6:49:37 AM EST
Got my replacement cyclinder this morning and just got back from the range..200 rds 100 wolf classic and 100 M855..all flawless..working great....Osprey you guys are the best
Link Posted: 3/22/2010 11:16:22 AM EST
I got word this morning that my new piston setup has shipped.  I'm sold on piston systems.  I'm debating now whether I want to get another Osprey kit or try something different.  I'll probably go with the Osprey because of the lack of springs, lack of noticeable carrier tilt and the customer service.
Link Posted: 3/22/2010 11:46:02 AM EST
Osprey will also sell replacement parts so plenty of support there.I have an ARES but thats on the beater..but I just sent out money for another OPS 416 today.If I were to go to a different system it would probably be adams arms but the Osprey design and function is what fills my needs best.
Link Posted: 4/6/2010 1:22:59 PM EST
I am curious about the Osprey system but it looks like it adds a whole bunch of moving parts to "fix" a direct impingement system that consists of a simple tube. How reliable are these retrofit kits?
Link Posted: 4/6/2010 2:31:53 PM EST


My op rod does not freely move ether. ill post a newer video sometime today
Link Posted: 4/6/2010 4:29:14 PM EST
If the rod isnt moving freely could be the barrel nut needs adjusting.
Link Posted: 4/6/2010 5:16:16 PM EST
The system is kind of weird in the way that it installs.  I don't know that the op rod not moving freely is really a problem.  If it is getting jammed up because the barrel nut isn't aligned, that might stop it from operating.  If it's just rubbing on the delta ring spring or retaining clip, mind does too and it doesn't stop the system from functioning.
Link Posted: 4/6/2010 6:21:34 PM EST
Im uploading a video on it right now. ill link it when it gets done
Link Posted: 4/6/2010 7:26:39 PM EST

Ok have a look
Link Posted: 4/6/2010 7:43:41 PM EST

Ok have a look

ok, bitches. Mine does the same thing. I just turn the snap ring thing with a screwdriver until it stops rubbing.
Link Posted: 4/6/2010 8:00:47 PM EST
i cant turn it at all cuz there's not room too. ill just have to let it rub it
Link Posted: 4/7/2010 11:33:08 PM EST
Thanks for the vid.

Wow, are you kidding me? The piston moves/rubs against the delta ring/barrel nut? That's a pretty dumb idea. Eventually that piston is going to get worn down. They should at least have the piston moving inside just the upper receiver
Link Posted: 4/8/2010 3:27:18 PM EST
If you are concerned about it rubbing just push the snap ring over a bit, that's what I did.  It doesn't take too much effort, and the snap ring will rotate on the barrel nut.  If the delta ring and/or snap ring aren't centered, they will rub on the op rod.  I'm not sure why this comes as a suprise.   There is plenty of room for a small screwdriver, punch, or something similar.  You don't have to spread the snap ring, just push on one of the ears and it will move.  


Ok have a look

ok, bitches. Mine does the same thing. I just turn the snap ring thing with a screwdriver until it stops rubbing.

Link Posted: 4/8/2010 4:59:14 PM EST
Thanks for the vid.

Wow, are you kidding me? The piston moves/rubs against the delta ring/barrel nut? That's a pretty dumb idea. Eventually that piston is going to get worn down. They should at least have the piston moving inside just the upper receiver

Doesn't every piston system have it's rod go through the same area? I don't really understand what you are trying to say.

And the snap ring thing he already explained it.  His has less gap on his snap ring than normal.  So it rubs no matter what.  A solution to that can be to file/grind the gap to open it up a little.
Link Posted: 4/9/2010 4:00:05 AM EST


Thanks for the vid.
Wow, are you kidding me? The piston moves/rubs against the delta ring/barrel nut? That's a pretty dumb idea. Eventually that piston is going to get worn down. They should at least have the piston moving inside just the upper receiver

Doesn't every piston system have it's rod go through the same area? I don't really understand what you are trying to say.
And the snap ring thing he already explained it.  His has less gap on his snap ring than normal.  So it rubs no matter what.  A solution to that can be to file/grind the gap to open it up a little.

The delta ring and the spring moves slightly all the time. The difference is that the direct impingement gas tube was never designed to slide around on the ring and spring. It just sits there.
The piston in the AK-47 moves around in a low-friction environment. The front part of the piston slides in and out of a specially designed chamber (chrome lined) with special flutes in the gas tube that facilitate low-friction sliding. It's supported and designed to do that.
In the case of the AR15, you have lots of edges: delta ring, spring, snap ring, the "X" hole in the upper receiver, etc... I'm sure the OEMs are claiming X number of rounds fired with sand/mud/concrete/ice/lava/angel dust caked in the system, but it seems like a problem looking for a solution especially with that many parts moving around.
I'm still considering an Osprey or any piston retrofit kit as a fun project, but so far I don't like any of the designs the more I examine how they work.
Link Posted: 4/9/2010 4:35:20 AM EST
I will say this for the Osprey as I have 3 kits on 3 rifles..it doesnt matter if you twist the handguards to make contact with the rod it does not bind or stop the rod im sure if there was a problem with that Osprey would have known in the 3 years of testing before the release.I dont know if its a problem with other systems but not with Osprey.
Link Posted: 4/10/2010 4:27:01 AM EST
I understand it will function, my concern is long-term longevity of the rod. Would it wear down from rubbing against the upper receiver, delta ring/spring, etc...?
Link Posted: 4/10/2010 6:45:50 AM EST
Doubt it would due to materials used. I don't think the aluminum parts would do to much to the steel Osprey Defense has used on their product.
Link Posted: 4/10/2010 5:22:58 PM EST
Just tested my new Osprey 416 and it worked GREAT! Even put on my Advanced Armament M4-1000 and the system worked like a fine tuned engine.
Link Posted: 4/18/2010 9:19:14 AM EST
Just an update.  I've been running the system for a little while now.  I have six or seven empty boxes that the Silver Bear came in and two empty boxes of M193 that came on stripper clips, so I have at least a few thousand rounds through the system.  It has run without a hitch.  At first I was worried about the Delta ring rubbing, the spring rubbing and the snap ring rubbing.  None of it affects the operation of the piston system and I haven't seen any wear on the parts of the system.

The only problems that I had, I believe were related to the DEZ barrel that I installed.  It is not chrome lined and I have found that I have to keep the chamber really clean or the Silver Bear ammo will wind up giving me problems with stuck cases.  I was also having a problem with the cam pin wearing a groove in the upper, but it turns out that this is common in rifles that are over gassed.  I pulled the barrel and compared the gas port to that of the port on a RRA barrel and found the port on the DEZ barrel to be a LOT bigger.  I'm in the process of sourcing a "better" barrel.  It's really a shame because I like the way the DEZ barrel shoots.  It's really accurate, but the trouble shooting Silver Bear is enough to force me to change the barrel for one that is chrome lined.  At around $135 per 500 shipped, it allows me to shoot A LOT.

I have to say that I called Cory at Osprey about the groove that was being cut into my upper.  It is obviously the fault of the too large gas port in the barrel, but Cory insisted on trying to fix my problem, even though it wasn't the fault of the piston system.  He proposed going with a slightly under sized piston to allow a bit more blow by.   I told him not to worry about, but he insisted on sending me another piston.   I thought I'd mention that because in this day and age where finger pointing is usually the norm with customer service, I found Cory's response to my problem to be refreshing and reassuring.

At this point, my only problem with the Osprey system itself is the lack of support in the area of handguards.  I haven't had a single problem with the system itself.
Link Posted: 4/18/2010 9:26:21 AM EST
I also wanted to mention that the way the Osprey system is apparently designed to need only a small amount of gas to operate correctly.  At least, less than a DI system.  I've shot some real crap (low velocity) ammo through the Osprey equipped carbine and it will eat some stuff that other DI rifles won't.  The blow by is also a non issue.  Since the system doesn't "vent" but only "leaks" gas under the handguard, it is clean.  Although I it does leak under the handguard, I haven't found the need to go out of my way to clean under them.  I'll wipe them out if I happen to have to take them off, but don't go out of my way to do it when cleaning the rifle.
Link Posted: 4/18/2010 12:59:31 PM EST
The beaUTY of a metered gas system..Tony I just got a POF roller cam pin and it makes thing cycle just that smoother..way less resistance than a regular cam pin.
Link Posted: 4/18/2010 1:03:07 PM EST
That's what threw me off about the wear.  I'm running a POF cam pin too and it really surprised me.  As mentioned above, it turned out that my gas port on the DEZ barrel is a lot bigger than that of my RRA barrel.
Link Posted: 4/19/2010 9:31:36 AM EST
Your oversized gas port could also be the problem with cases sticking in the chamber. The bolt pulls back trying to extract to quickly before the pressures drop to allow extraction. The case is still expanded to tight against the chamber wall.

I got a replacement piston for my 11.5" upper last week but have'nt had the time to try it out yet. The kit was part of the first run that has sat on my bench all this time waiting for my stamp to come in. Once I finally got it built it short stroked every shot so Corey sent an updated piston. Hopefully thats my problem.
Link Posted: 4/19/2010 11:11:09 AM EST
M1, I hadn't thought of that either.  The over gassing causing the cases to stick, that is.  I was wondering why I wasn't having any problems with my other DEZ barrel as it is also non chrome lined.  In any case, I finally took a step toward what I really want.  I ordered a Bushnmaster 14.5" setup last night.  I hope that it runs the Osprey system.  I'm also hoping that the shorter dwell time will take a bit of the harshness out.

Live and learn.
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