PWS Piston System

[Outlander Systems]

Anyone have any experience with these?

I'm considering a piston retrofitting of one of my blasters, and wanted to get some M4C, real-world advice, before taking any steps forward on this.

[Outlander Systems]

Found GotM4's Post, and borrowed/stole some info to re-post here.


"If you are planning to build or buy a SBR or full auto or use a sound suppressor, I would suggest considering a piston gun.

Many people think they need a piston AR or they need to convert their standard AR to piston. Many of these people use the excuse that piston ARs run better than direct impingement ARs or run cleaner. This is not the case. Piston guns have their own sets of known problems. These are just different problems and weakness areas vs. standard direct impingement ARs.
Piston guns get dirty as well just not at the bolt, bolt carrier and in the upper receiver, piston ARs are more forgiving of the lack of lubrication (because the bolt and carrier aren't getting as hot and hot gas isn't blown into the action), they can be run with a little less lubrication than direct impingement ARs. I have the Primary Weapons carbine length piston conversion on my Colt 6920 upper. It gets plenty dirty. After a thousand rounds or so it looks like I've airbrushed carbon all over the gas block and the rail and barrel near the gas block. This is where it bleeds off the excess gas not used to cycle the bolt. If shooting without a glove on my left hand it gets very hot in this area pretty quickly, actually hotter than comparable direct impingement ARs.

Many piston ARs suffer from bolt tilt. Bolt tilt is where the carrier bottom side at the rear of it is slammed downward as it cycles, as the carrier tilts downward the first thing the carrier impacts is the bottom of the receiver extension and this causes gouging the receiver extension near the buffer retainer. These gouges can get so bad that the rifle will have some very unusual hard to diagnose stoppages which include short stroking, failures to feed etc. I have a friend who has over 20K rounds through his piston gun and it looked like someone took a rat tail file to his receiver extension. He's also now running an experimental anti-tilt buffer as am I. I'm using this experimental buffer which addresses these tilt problems, and it is working very well at stopping bolt tilt 100% so far. The Primary Weapons conversion does have least amount of tilt for conversion units, mine wasn't bad even before using the anti-tilt buffer but the carrier did remove a little of the finish from the inside of the bottom of the receiver extension. After getting the new anti-tilt buffer I started fresh with a brand new LMT receiver extension to track any changes .

Standard direct impingement ARs don't have bolt tilt issues because the gas chamber is in the center of the carrier and when the gas is expanded in that chamber this expansion forces the bolt carrier rearward and the bolt forward until the carrier moves far enough rearward that the bolt unlocks and follower the carrier rearward.

Piston ARs have bolt tilt because they have a solid mass (not gas) impact the top front of the carrier, or they have carrier key which is impacted by the op rod which is mounted high on top the bolt carrier. The natural first movement of the carrier is to cam down slightly before starting rearward. If not addressed this is why there is gouging at the receiver extension near the buffer retainer. Some companies address this with pads at the tail end of the carrier to limit the amount of tilt.

I run my piston AR almost as wet as my standard direct impingement ARs. If you are using a sound suppressor your bolt will run cooler, but it'll still be pretty dirty along with the chamber and barrel. So “easier to clean” is a very poor excuse for wanting a piston AR. The rail, inner sides of the rail covers and portion of the barrel around the gas block on my piston AR looks as if someone airbrushed carbon all over it. So it still gets dirty, it's just in a different spot vs. a direct impingement AR. I believe if one is too lazy to clean and properly lube an AR then one should just shoot an 7.62x39mm AK. This isn't a dig at AK owners because I am one. I currently have 3 and like them a lot. AKs can be shot for a long time with very little cleaning and very little lubrication. Many of the people who think a piston AR is as reliable as an AK also believe that 5.56mm is a poor caliber for defensive use. As a whole, piston ARs aren't anywhere near as reliable as an AK as many people believe. Some are very reliable, the HK416 is one example. Piston ARs vary quite a bit from one brand to another and they aren't created equal. There is no standard for piston ARs."

I might be reconsidering a Piston Conversion after seeing this. I was under the misinformed position that the Piston Conversion would allow for less burning of 'lube, and allow longer periods of firing without cleaning/lubing.

[Seth Harness]

I received a GPU upper from ADDAX Tactical last week, the purpose is to test the upper with the Anti Tilt Buffer. They use the PWS kit, I havent shot it yet, but the fit and finish are freaking beautiful. In my opinion, this is one of, if not the best kit(s) on the market. From what I've heard, they've worked out the parts breakage issues, then again I only hear from a couple sources. I would put one in my gun for sure... And with a new anti tilt buffer, the kit is even better.

[Outlander Systems]

Good to know. I was curious as to the quality of the manufacturing of the system itself, so it's nice to hear that it's GTG kit.

Who's offering the anti-tilt buffer?

Can I push you to do a range report after the T/E?

[Seth Harness]

Who's offering the anti-tilt buffer?

I will be, Chris (owner ADDAX Tactical) and I have been talking quite a bit about him carrying these when the T&E is finished and all aspects of the buffer are final. Both, sold with his ADDAX Tactical GPU's and selling them outright as well.

Can I push you to do a range report after the T/E?

You bet man, the buffer is getting sent out for another, different trial coating. When it returns I'll shoot/test and post the news. Keep an eye on the anti tilt buffer thread, I'll update there.

If your interested in checking out ADDAX Tactical/Chris' uppers, heres a link. There are some good pics of the PWS kit on his site as well.

[SeriousStudent]

Thanks for the update, Seth. I have that other thread of yours bookmarked. Yours and Robb's input are the reason I have held off buying a piston AR until the tilt issue is "resolved."

I'm looking forward to buying either a 10.5 or 12 inch suppressed SBR. But it will likely be the only one I buy, due to the paperwork and costs involved. I want to do it right the first time.

Good luck with your work. There are a lot of us watching with interest.

[Cameron]

This little SBR is running the PWS system in it and it runs like a champ.

With a can, full auto, all ammo types, it has been 100% reliable without an problems at all. Nice and easy to clean and the bolt stays MUCH cooler. PWS has a very well thought out and simple system, I am thinking of getting another 10" upper and I will get the PWS system in this one also... as soon as I can find the upper at a decent price.



Here is my wife shooting it...



and me... bad mag failed to lock the bolt back, does it in all ARs...

[SeriousStudent]

Very nice SBR, Cameron.

[Seth Harness]

Thanks for the update, Seth. I have that other thread of yours bookmarked. Yours and Robb's input are the reason I have held off buying a piston AR until the tilt issue is "resolved."

I'm looking forward to buying either a 10.5 or 12 inch suppressed SBR. But it will likely be the only one I buy, due to the paperwork and costs involved. I want to do it right the first time.

Good luck with your work. There are a lot of us watching with interest.

Thanks man, I sincerely appreciate your interest.
-------------------------

BTW- Cameron, that gun is hot man. I gotta move to a different state...

[Addax]

I will be, Chris (owner ADDAX Tactical) and I have been talking quite a bit about him carrying these when the T&E is finished and all aspects of the buffer are final. Both, sold with his ADDAX Tactical GPU's and selling them outright as well.





You bet man, the buffer is getting sent out for another, different trial coating. When it returns I'll shoot/test and post the news. Keep an eye on the anti tilt buffer thread, I'll update there.

If your interested in checking out ADDAX Tactical/Chris' uppers, heres a link. There are some good pics of the PWS kit on his site as well.

The buffer we have for T&E is Excellent, Thank you Seth!

I have tested it with one of my 6.8 Gas Piston Uppers I built and I am going to be testing another one soon on a SBR Gas Piston Upper I am building specifically for extended T&E.



Thank you Seth!