Hi,
I am hoping those familiar with PWS can provide some insightful information. How many generations are there? Are there photos available of the differences between generations? Are there any issues with any of the generations?

I have searched online and the information is limited. I have found some videos of PWS not cycling properly which I found surprising considering the passion some people express about PWS.

Thank you.

The Gen 0 used a rigid non-free float quad-rail forearm, a fixed gas block, and a pinned piston head.

The Gen 1 uses a free floating Keymod forearm, a 4 setting adjustable gas block, a removable piston head and the bolt carrier is now nickel teflon coated.

THe only cycling issues I've heard are Gen 0's running suppressed, the Gen 1's adjustable gas system should address that.

Gen 0 Mk 114 on top, Gen 1 Mk116 on bottom.

That helps me understand this much better. I have been calling PWS for answers but no answers their phones nor returns messages.

Thank you very much for the feedback, pictures and details.

After thinking about it those changes between generations is substantial.

Wow! I've never had a situation when I send an email or call that I haven't gotten either Stacy Nagy or Owen in Customer Service answer. Hey, it could happen, I've just never experienced it. PWS has a reputation of stellar Customer Service.

Anyway, there's an even earlier version. A completely different design concept, which actually included a 'short throw' Gas Piston and a long Operating Rod and Key permanently affixed (properly Staked) to the BCG. The piston moves about a  1/4" within the Gas Block and impinges on the tip of the Operating Rod moving the BCG out of Battery and cycling the Action.

It was available as a 'conversion' by PWS authorized shops. I had my '2005 Bushmaster 'converted' in '2008 by ADDAX Tactical. ADDAX workmanship was excellent. While they had it, I went ahead and had them permanently attach a PWS FSC 556 Muzzle Device, Daniel Defense Omega Quad Rail and Troy BUIS. I still have the rifle and it shoots perfectly and shows no signs of Bolt Carrier-Tilt. That design will eventually exhibit 'Bolt Carrier-Tilt'. However, the rifle will probably have 25k (maybe more? IDK) rounds through it when it does. And, it's operational life may only go to 25k to 30k plus rounds and I'll have to get another Lower Receiver Extension, a.k.a., Buffer Tube.

What I'm trying to say here is, based on the way I shoot, I'll probably never see the replacement of the 'Buffer Tube' at 25k plus rounds. Besides, the barrel life may be completely exhausted depending on your individual accuracy requirements.

The new 'Long-Throw Gas Piston System' has done away with any Carrier-Tilt issues and based upon a fellow who goes by the handle 'DMack' at Ranger Proof, has done a long-term Test & Evaluation with a documented 38k rounds through the Mk114 mod 0 version as of December '2014 and the rifle still holds 'tight combat accuracy'. He's an LEO Trainer and uses his guns hard.

Best regards,

Old_Navy

I called the number on their website and tried every available extension multiple times including "Accounting", no one answers. Tried on different days too at 3pm during the week. Left a message too, no one has called back...

kippjones...I just received an email from 'Owen' at PWS Customer Service on Friday, so I know they are there. The phone number I use is 208-780-6122. Either Stacy Nagy or Owen always answer. I can't explain your issue.

Best regards,

Old_Navy

The Gen 0's had problems with the gas block. The material spec and some dimensions were incorrect  and as such, suffered failures.

Not sure how many of these made it into consumer hands, but it was corrected.

Shadow_Dancer...can you please elaborate on the Gas Block issues causing failures? As I understood the gas issue, it had to do with Suppressor use and having to use different weight Buffers depending upon the Suppressor. Since the use of Suppressors has become more prevalent in the civilian sector and designs differ from Suppressor to Suppressor, an adjustable gas block was in order. Also, the gas issues I heard of had to do primarily with SBR guns.

Again, I refer to the DMack Ranger Proof Long-Term Test & Evaluation on The Sniper's Hide. DMack used his Mk114 Mod 0 with Suppressors and had no issues, but was quick to point out, Suppressor use with an SBR (which he also owned, see below) was a different case.

02-12-2012, 08:04 AM DMack states, "The MK 112, MK 114 and the MK 116 do not need an adjustable gas block. The MK 110 runs well with SOME suppressors, but it is offered as a MK 110B that does have a different gas block. The MK 107 runs fine so far, with the Brevis Delta P suppressor attached. I would call Stacey and ask about specific suppressors and rifle combos. Not all suppressors are created equal."

Best regards,

Old_Navy

Thanks, I will try again Monday.

Mr. Shadow_Dancer...I have done numerous Searches on the WWW and I can't seem to find any reference to "...material spec..." or "...dimensions were incorrect..." and "...suffered failures...". Can you please point me to those documented occurrences? I'm interested in reading about those issues.

Best regards,

Old_Navy

Hi Navy,
Sorry, haven't circled back on the board in a minute.  You'll probably find very sparse material on the subject. I'll contact you via PM.

Sorry, A little off topic here.

Why did they go away from this early set up? It seems to me that the tube that the op-rod rides in helps prevent carrier tilt. I have one of these and really like it.

Sorry, I haven't kept up with these over the last few years. How does the newer versions improve the PWS piston concept?

Mr. mouthpiece...The short answer is, the old design will exhibit "The Dreaded Carrier-Tilt" and wear out the Lower-Extension (a.k.a., Buffer Tube) and possibly wear away part of the Upper-Receiver, damaging it. Depending how you shoot, it could happen somewhere within 25k rounds. Or, there about.

The new 'long-stroke' design also has a full-length gas tube like the previous design. Essentially acting as a 'Cylinder'. The Operating Rod is larger in diameter, therefore more robust. PWS basically flipped the 'piston' 180-degrees and attached it to the end of the Op Rod. Very AK'esque. This makes a solid and linear transfer of energy from the siphoned off gas in the Gas Block to the piston, modified Gas Key and Bolt-Carrier Group. The PWS Mk 1 series Bolt-Carrier itself has more bearing surface on the rear which helps, also. Together with the new "Enhanced Buffer Tube (EBT)" and it's lower-lip extension, virtually nullifies "The Dreaded Carrier-Tilt".

BTW, I still have my ADDAX/PWS/Bushmaster conversion and the rifle operates flawlessly and exhibits no signs of "The Dreaded Carrier-Tilt". Of course, I have nowhere near 25k rounds through the gun.

I hope this crude and inarticulate attempt to describe the 'New' system helps.

Best regards,

Old_Navy

What is the barrel twist rate on the MK 114 Mod 0?

I believe PWS uses 1:8 twist in all their 223 guns.

Wlyde chambered - 1:8 twist.