Here we go again...

[mrraley]

As everybody knows, there is and always be the debate or argument over DI (direct impingement) vs. piston rifles.

Well the topic has been brought up again by Gabe Suarez. I have tried to put up my comments or arguments and they just have a tendency to go to the way side since I'm not one of his kool-aid drinkers, trying to brown nose him, or ride his johnson...

So by the grace of GOD and with your permission, I am going to post his article and my arguments here to reach the better public to read.

I understand this is just a point of view, rant, soap box, opinion, or what have you, and you know what they say about opinions’ too… they are like assholes, everybody has one, and some of them really stink.

Warrier Talk News

Thanks for taking the time to at least look in and give it a glance…

[Madhouse]

just like Ford v. Chevy v. Dodge

<munch>

[mrraley]

But on to the point!

Nothing is perfect, and in seeking to make it perfect, we do in fact make it better. Those who are invested in doing this one way will resist any deviation from that path...even though subsequent paths will be faster, and well...better.

The AR/M4, like it or not, has a reputation for being unreliable. Whether one particular AR has gone 150,000 rounds (like Chuck Taylor's Glock) is not relevant to the discussion. The reputation remains as much as that of the AK not being accurate.

Just as attempts to make the AK more accurate are warranted, so are attempts to make the AR more reliable. One of those attempts has been the use of a Piston in lieu of the Direct Impingement.

*The AR style rifle is and can be considered a piston operation:

Piston definition from Merriam Webster Student Dictionary: Function: noun, : a sliding piece moved by or moving against the pressure of a fluid (as steam or hot gases) that usually consists of a short solid cylinder moving within a larger hollow cylinder.Piston definition

Go to any forum where there are a higher number of DI makers advertising and the Piston AR is reviled as if it were the product of Lucifer himself. And of course, the only DI guns worthy of consideration are those sold by the advertising companies....who also happen to be on some arbitrary list. Yet go to a forum where Piston guns advertise more and DI is seen as some backward rifle akin to a crossbow. With the guns sold by the companies in question being the only choice.

*The piston rifle itself was designed as a solution for a problem that never existed.

Now is being looked at as the next best thing since sliced bread.

Business is business and nobody can blame them. But I must say...after studying the matter thoroughly, the piston AR is an improvement over the Direct Impingement concept. Argue if you will but that is the conclusion I arrived at on the matter. I suspect this will create at least twelve pages of excoriation at one of those wannabe AR-15 forums.  Well, I hope at least the get the URL correct.

*A one person conclusion with no scientific data as back up or proof.

In subsequent discussion we will discuss which guns are the best value and why (HK416 vs. LWRC vs. SIG516....for examples), as well as answer the detractions of the piston concept.

DI Gun Advantages -

1). It will cost the buyer less money. I do not use the "C" word (cheap). That can be good or bad depending on what you get. A WASR 10 will also cost less money, but it is hardly anyone's first choice. A rotary dial phone will still work, but it hardly the best choice today.  DI gun can be very good...but it is still a DI gun.

*No information listed here, personal speculation.

2). Lighter recoil than Piston Guns (are we realy comparing the recoil of a 5.56!!??)

*Recoil is recoil, take it for what it is, you don’t want to feel recoil… don’t shoot.

3). One thing you commonly hear is that it has commonly available parts. Well we need to qualify that. If you have the parts in your possession that is fine. if not, you will have to order them. Not being in a military role, that is what you will need to do anyway. So if you simply buy what you need beforehand, and have it available, it is really as much a non-issue as AK-magazine availability.

*Again, no pertinent information listed here, personal speculation.

(NOTE: Notice that there are only 3 “DI Gun Advantages” listed and yet none are actual advantages. Another way for the author to stack the article in his favor.

Piston Gun Advantages -

1). Avoids the fouling and carbon build up common in DI guns. Fouling is the main cause of the AR's unreliable rep. Fix that and you have a new animal altogether.

*Personal speculation. With proper care and maintenance, a DI rifle will run great.  Something not covered or explained.

Q: How does it “Avoid fouling and carbon build up”?

A: It doesn’t. It just puts them in another location to clean.

2). Did you know that an M4 in service is intended to be rebuilt every few thousand rounds? The parts wear out. That is directly from a US Army M16 Armorer. A Piston gun, OTOH, does not heat the internals of the gun as much as DI guns. That means that the various small internal pieces and springs will not get subjected to the heat in a DI platform. That translates into far longer service life and enhanced reliability.

*An educated person that can read a military TM (technical manual) would understand that. It is called Preventive Maintenance Checks and Services (PMCS). Parts have a tolerance of + or -. As long as it is within that range, it is functional. If it is out of that range, replace it.  So it doesn’t translate into anything. Again with proper care and maintenance you can have a long life too.

3). In our in house testing, I have found the piston guns to cycle faster than the DI guns. Not a conclusive, split-time examining test, just a feel. On the DI guns you can feel the action working between shots. On a piston gun, it is press trigger, shot out. Perhaps we need to dwell in this area a bit more.

*”In house” fancy for saying we took it outside and shot it No “conclusive” “just a feel” another way of saying he has a highly calibrated shoulder. Of course you can feel the action work on either rifle, just depends on how fast you pull the trigger.

* No way to prove that the cycle of operation was faster on either rifle until you strip them down side by side and verify that the SAME amount of gas is doing the same work on both rifles. Meaning to check the gas port size in both barrels to ensure the same amount of gas is the same at the start.

4). Ease of maintenance is only overshadowed by ease of replacement. Carrying a spare anything with you is as easy as it is with a DI gun, but only easier to replace.

*How would this be “ease of maintenance”? Let alone “ease of replacement”? Because there are more moving parts in the piston rifle than the DI rifle.

5). Finally, the piston gun keeps the blowback out of your face and nose and lungs. We hear all manner of dram from "second hand smoke" yet we hear nothing about the lung-full of gas the DI shooter gets everytime he touches off a shot.  I wonder if the Piston Guns are..."healthier".

*Healthier? We’re talking about combat shooting, shoot move and communicate. If you move god forbid you take a breath in and get that nasty stuff in your nose or mouth. Simple solution… DON’T SHOOT.

One cannot have a discussion of the Piston M4 without the HK416 dropping in. I am not certain if it was first, but it certainly was the most marketed, and of course...it is a top choice among US Special Ops. Using an HK416 to kill Bin Ladin was a telling rebuttal to "piston dtractors". These guys...the Special Ops guys tasked with the mission could have anything they want as money is no object. Yet the gun they used, and use, is not a Direct Impingement Rifle.

Ernst Mauch, at HK, was tasked with an improvement program for the M4 as far back as 2001 and one of the primary issues faced was the DI gas system. Rather than build a "faster horse", Mauch went with the proven successful piston system as is seen in the G36. In less than two years, including time wasted fighting a lawsuit by Colt. I find it amazing how often American companies, resting on their laurels, fail to innovate, and get legally upset when a disruptive company does what they should have done all along.

*Notice that he mentions “improvement program” as far back as 2001. That is because they have not been able to solve the one problem that piston rifles have over DI rifles. And that is carrier tilt, resulting in bolt breakings at their weakest point.

The advantages of the 416 over standard DI M4 are well documented in the various tests conducted. Those advantages are of course said to be inconsequential by HK's competitors. What would anyone expect them to say....that yes, the HK is better? Unlikely.

*What advantages? What tests? And yes they are inconsequential by competitors as it was conducted by HK and stacked in their favor. So again, what scientific proof is there for back up?

The issue with the HK is simply that Heckler & Koch was damaged in 1994 when the AWB took place and, rightly so, they saw the US Civilian market as too unstable to mess with. This has changed of course, and many companies came back after 2004, but not HK. Their standing in the civilian market is poor. But one has to mention the 416 in any discussion like this as it is the gun that other try to emulate.

*It’s not that their standing in the civilian market is poor; it’s that the general civilian market can’t afford their line of rifles and goes with the least expensive thing they can get their hands on. Since he wouldn’t use the “C” word, I won’t either.

[edgecrusher]

thanks Pat, this is a everlasting arguement…. except one one side gets to argue usually, and that's the piston side. I have both, albeit in two totally different rifles. (20" Larue OBR, DI, set up as a "sass" with optics, prs, ect. and a 14.5" pws mk214 piston gun with irons and a light, more for a light battle type rifle.) I personally feel that for a civilian or hobbyist, the DI will never, yes never, fail you unless you don't care for your rifle for years! Even military usage will not encounter problems because they clean their rifles.

I think the only real advantage piston guns may excel at is full auto use, where it will use it's strong points to keep the weapon cooler and cleaner in situations where thousands of rounds will be fired in a single session.

just my opinions, coming first hand from what I have experienced. thanks for posting that, it should be interesting to hear everyones point of view

[mrraley]

I was told one time, that for a percision rifle the DI would be better and with select fire rifles the piston is better.

I do not have any experience with the select fire rifles in a piston system so I can not judge them on that.

But with you bringing that up, edgecrusher, it puts more credit into it for me than hearing it from just one person that I wasnt sure with in the first place.

Another point that I wanted to add is that a piston system also has more moving parts now too.

[Magwa]

thanks Pat, this is a everlasting arguement…. except one one side gets to argue usually, and that's the piston side. I have both, albeit in two totally different rifles. (20" Larue OBR, DI, set up as a "sass" with optics, prs, ect. and a 14.5" pws mk214 piston gun with irons and a light, more for a light battle type rifle.) I personally feel that for a civilian or hobbyist, the DI will never, yes never, fail you unless you don't care for your rifle for years! Even military usage will not encounter problems because they clean their rifles.

I think the only real advantage piston guns may excel at is full auto use, where it will use it's strong points to keep the weapon cooler and cleaner in situations where thousands of rounds will be fired in a single session.

just my opinions, coming first hand from what I have experienced. thanks for posting that, it should be interesting to hear everyones point of view

  I agree with you 100% most civilian guns will not be shot over 5 thousand rounds and with almost no care a DI gun will function just fine and i also agree that these 3 to 4 thousand dollar guns are NOT going to be bought in any large amount by civilians we simply do not have the bucks..

[338FedAR10]

3). One thing you commonly hear is that it has commonly available parts. Well we need to qualify that. If you have the parts in your possession that is fine. if not, you will have to order them. Not being in a military role, that is what you will need to do anyway. So if you simply buy what you need beforehand, and have it available, it is really as much a non-issue as AK-magazine availability.

*Again, no pertinent information listed here, personal speculation.

In another article i read on this debate this point was raised. With a little added to it. With DI you get the standardization of parts, while with the piston you have many different manufactures with many different designs, parts, and features. So if five years from now your manufacture was to tank, or switch designs, the only maker of parts was them. Where as if i buy a Bravo Company BCG and tomorrow they disappeared, i could still find 10 other makers that would work.

[tg4360]

One thing the guy doesn't seem to think about is that, perhaps a SEAL team would prefer a piston gun due to the possibility of better functioning after having been submerged. 

I'm just thinking of the top of my head that a gas block and short piston and op rod would be much easier to clear of water than a gas tube.

You might even not have to do anything but let it drain for a moment to get it into action vs. I can see that surface tension and capillary action could keep a slug of water in the gas tube and make it difficult to clear.

[unforgiven]

Good one brother Pat <thumbsup>,The other thing that I have read is piston rifle can be adjusted for suppressors.Is that adj. that important? Don't guys run suppressors on D.I. rifles?I would like a Huldra piston upper just to run steel through it as I will only run brass through my .....can I say it Pat.. RRA <lmao>.LWRC is damn nice rifle but I can't afford it. :(

[planeflyer21]

Something I haven't seen mentioned, Stoner felt that there were some short comings with his AR DI system and the way the military was using it/feeding it.

So he developed the AR-180.  Stamped steel and piston system.  Where are the millions of those now?  Oh yeah...they didn't build them by the millions.  Although that may be more due to mismanagement on the part of the few companies that went to produce it.

Like I said before, with .308s at least, ask the piston-boys about bent oprods.  To have a rifle (or any firearm) that comes with a list of loadings range that you need to stay in is a bit silly.  It is one reason I haven't bought a Smith 25 in .45 Colt...I want to push a 300gr pill FAST.

I only recently learned that the AR system isn't the only DI system out there.  The FN MAS series of rifles is also DI but where the gas hits the bolt carrier is outside of the receiver, thereby venting the gases out into the air rather than into the receiver area.

Anyone ever try to do a real good cleaning on a surplus SKS piston system?

Jon

[98Z5V]

I really need to read this whole thing, and especially what mrraley posted in entirety, before I comment with both feet, buuuuuut...

The DI gun is proven.  The DI gun is a "piston gun,"  Lot's of people don't get that.  The bolt in a DI gun has gas rings, and it's cycled by gas pressure - that thing is a damn "piston" by definition.

I think that by moving that "piston" forward, you introduce more parts, more parts that can get damaged, and more weight forward - where you don't need it, at the muzzle.  Sure, you get the heat forward, but where is your support hand?  Forward. 

Non-thought out comments, off the cuff. 

I'll take DI any day of the week. 

[planeflyer21]

Honestly, I don't really give a crap.

It is like arguing which is better, lever-action or pump-action, or is a cammed bolt-action better than a straight-pull bolt.

If it hits where I'm aiming by golly that is good enough for me.

Jon

[mrraley]

If you go to the blog and actually look at some of the replies that are posted on there the sheeple are following closely on every word he says.

[edgecrusher]

If you go to the blog and actually look at some of the replies that are posted on there the sheeple are following closely on every word he says.

Of course, he's a pro!  :hail:    :strokin: