AR Sponsor
Posted: 11/11/2010 8:57:17 AM EDT
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Pistons in ARs usually show signs of carrier tilt especially from conversion kits...
...unless you go with HK, which to my knowledge is the only manufacturer that has really created an AR piston system that functions flawlessly. HK is the only piston system I would buy personally, and I plan to get one. :D Generally though even w/o carrier tilt etc. pistons have a slower RoF and more complicated/expensive to fix, but are much more reliable and function better in harsh environments I wouldn't buy an LWRC piston AR or anything like that... if I went piston, HK only IMO. The G36 is one of the best rifles around and they moved that system (with rotating lugs) over to their HK416/MR556 etc. |
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Quoted: Pistons in ARs usually show signs of carrier tilt especially from conversion kits... ...unless you go with HK, which to my knowledge is the only manufacturer that has really created an AR piston system that functions flawlessly. HK is the only piston system I would buy personally, and I plan to get one. :D Generally though even w/o carrier tilt etc. pistons have a slower RoF and more complicated/expensive to fix, but are much more reliable and function better in harsh environments I wouldn't buy an LWRC piston AR or anything like that... if I went piston, HK only IMO. The G36 is one of the best rifles around and they moved that system (with rotating lugs) over to their HK416/MR556 etc. So much fail... The HK was found to be lacking, severely. |
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Pistons in ARs usually show signs of carrier tilt especially from conversion kits... ...unless you go with HK, which to my knowledge is the only manufacturer that has really created an AR piston system that functions flawlessly. HK is the only piston system I would buy personally, and I plan to get one. :D Generally though even w/o carrier tilt etc. pistons have a slower RoF and more complicated/expensive to fix, but are much more reliable and function better in harsh environments I wouldn't buy an LWRC piston AR or anything like that... if I went piston, HK only IMO. The G36 is one of the best rifles around and they moved that system (with rotating lugs) over to their HK416/MR556 etc. So much fail... The HK was found to be lacking, severely. The XM8 scored the best, with only 127 stoppages in 60,000 total rounds, the FN SCAR Light had 226 stoppages, while the HK416 had 233 stoppages. The M4 carbine scored "significantly worse" than the rest of the field with 882 stoppages. It's "lacking" yet still fielded by almost every SOF? So lacking that the Marines are thinking about swapping all of their SAW LMGs for HK416s? So lacking that it has OTB & a CHF barrel compared to the traditional Colt? So lacking that it has one of the most successful gas piston systems in it (from the G36)? |
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Pistons in ARs usually show signs of carrier tilt especially from conversion kits... ...unless you go with HK, which to my knowledge is the only manufacturer that has really created an AR piston system that functions flawlessly. HK is the only piston system I would buy personally, and I plan to get one. :D Generally though even w/o carrier tilt etc. pistons have a slower RoF and more complicated/expensive to fix, but are much more reliable and function better in harsh environments I wouldn't buy an LWRC piston AR or anything like that... if I went piston, HK only IMO. The G36 is one of the best rifles around and they moved that system (with rotating lugs) over to their HK416/MR556 etc. So much fail... The HK was found to be lacking, severely. I couldn't even think of a way to respond to that one...good job, JA. |
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Piston on AR Platform
-unreliable, -way over-gassed, beating up your internal parts -over-gassed because there's no DI action to assist in bolt unlocking, therefor the bolt must be forced out of battery by piston operation alone -heavy -inherently less accurate, due to the inability to float them -there's zero standardization of parts -over-priced AR are designed to use DI |
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Pistons are "gas operated".
The essential difference between "piston" systems and the standard AR15 configuration is where the gas does its work. http://www.ar15.com/forums/topic.html?b=2&f=130&t=165511 Read and understand this thread. In a "piston" system, the gas expands against a piston head that's located out on the barrel somewhere, with the mechanical action transferred via a metal rod. Gas is exhaused out of ports near the gas port, in most rifles, that means at the front of the handguards. In the standard AR, the gas expands against a piston head that's located inside the bolt carrier and is in fact the back end of the bolt. No mechanical transfer is required in this system. Gas is exhaused out of ports on the side of the bolt carrier and out the ejection port. There is nothing wrong with the principles of gas piston operation. However, the AR15 was specifically designed without certain engineering features that are used in piston operated arms to control various forces that are inherent in piston systems. Attempting to retrofit a piston onto a firearm design that lacks those features can introduce problems. Substantial redesign of the AR15 type would be required to integrate those features and you'd essentially have a new firearm. The vast majority of the reasons that people cite for desiring or buying piston ARs are just mythology/fiction and have no basis in reality. |
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Best to find a design that originated as a piston unit if thats what you desire. AR designed as gas-imp, stresses on parts from piston op not considered in original design...Has anyone here (outside of military combat) actually experienced a failure due to gas system fouling/heat on a PROPERLY maintained AR? .........crickets........
Now price both options.. ETA: Somebody link up the video from Colt where the M4 runs full-auto until the handguards and gas tube melt off. Ya, I guess the gas system did fail after 900 rounds of auto-fire..... |
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Piston on AR Platform -unreliable, -way over-gassed, beating up your internal parts -over-gassed because there's no DI action to assist in bolt unlocking, therefor the bolt must be forced out of battery by piston operation alone In DI operation the gas pushes on the back of the bolt, in a piston, that pressure is not there causing the polt to be pulled against the barrel ext as it unlocks, causing excess bolt wear. -heavy -inherently less accurate, due to the inability to float them -there's zero standardization of parts -over-priced AR are designed to use DI red print is my addition. |
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Quoted: It's "lacking" yet still fielded by almost every SOF? So lacking that the Marines are thinking about swapping all of their SAW LMGs for HK416s? So lacking that it has OTB & a CHF barrel compared to the traditional Colt? So lacking that it has one of the most successful gas piston systems in it (from the G36)? Which SOF unit is using the 416? Very, very few if any. AFIAK, none. The Marines I know, don't want that abomination to replace their 249s. Big deal on the barrel. It may have the piston from the G36, but what about the rails and everything else that actually makes a piston design succesful? There was a country in northern Europe, I forget the exact one, that adopted it. My understanding is that they've pretty much pulled every single one of them from service due to the unusually high number of issues they've been having with them. |
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Norwegians adopted the HK416 and they are having problems with it. https://www.defencetalk.com/forums/army-security-forces/norwegian-soldiers-having-problems-hk416-8873/
http://www.thefirearmblog.com/blog/2009/03/06/norwegian-soldiers-having-problems-with-hk416-2/ Quoted:
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It's "lacking" yet still fielded by almost every SOF? So lacking that the Marines are thinking about swapping all of their SAW LMGs for HK416s? So lacking that it has OTB & a CHF barrel compared to the traditional Colt? So lacking that it has one of the most successful gas piston systems in it (from the G36)? Which SOF unit is using the 416? Very, very few if any. AFIAK, none. The Marines I know, don't want that abomination to replace their 249s. Big deal on the barrel. It may have the piston from the G36, but what about the rails and everything else that actually makes a piston design succesful? There was a country in northern Europe, I forget the exact one, that adopted it. My understanding is that they've pretty much pulled every single one of them from service due to the unusually high number of issues they've been having with them. |
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Pistons in ARs usually show signs of carrier tilt especially from conversion kits... ...unless you go with HK, which to my knowledge is the only manufacturer that has really created an AR piston system that functions flawlessly. HK is the only piston system I would buy personally, and I plan to get one. :D Generally though even w/o carrier tilt etc. pistons have a slower RoF and more complicated/expensive to fix, but are much more reliable and function better in harsh environments I wouldn't buy an LWRC piston AR or anything like that... if I went piston, HK only IMO. The G36 is one of the best rifles around and they moved that system (with rotating lugs) over to their HK416/MR556 etc. Except that LWRC was the first company to pioneer the piston in an AR platform. And their guns have NO problems with carrier tilt. They were also one of the first to use nitriding and CHF barrels, now you're starting to see alot more companies using CHF barrels. Also, unlike HK, they did it within the confines of the AR platform's current dimensions. Instead of raising the top rail and needing special iron sights. To the other poster who said they cant be free floated. They are flat out wrong on that. Again, LWRC rifles are free floated. except for the m6, due to useing standard handguards, but thats a null point, as standard ar's arent floated either. |
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LWRC was the first company to pioneer the piston in an AR platform They were most assuredly NOT the first. Colt experimented with piston ARs in the 60s, and there was a commercially available conversion piston system called the "Rhino" that was sold in the 70s and 80s. |
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Hey, how about a moratorium on 'piston AR' theads? Mods, next guy that opens one, call in an airstrike on his E-address? In the meantime, how about everyone who wants a piston rifle so damn bad go and buy a SIG or a Mini 14 or a ShoSho gun? Jeeze, enough already. If talking about it solved the problem, there wouldn't be a problem, whatever the problem is.
Double palm plant indeed. Moon |
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It's "lacking" yet still fielded by almost every SOF? So lacking that the Marines are thinking about swapping all of their SAW LMGs for HK416s? So lacking that it has OTB & a CHF barrel compared to the traditional Colt? So lacking that it has one of the most successful gas piston systems in it (from the G36)? Which SOF unit is using the 416? Very, very few if any. AFIAK, none. The Marines I know, don't want that abomination to replace their 249s. Big deal on the barrel. It may have the piston from the G36, but what about the rails and everything else that actually makes a piston design succesful? There was a country in northern Europe, I forget the exact one, that adopted it. My understanding is that they've pretty much pulled every single one of them from service due to the unusually high number of issues they've been having with them. This flows with what I've been hearing. The 416 was a flash in the pan, that ended up being a dud. |
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Quoted: Quoted: Piston on AR Platform -unreliable, -way over-gassed, beating up your internal parts -over-gassed because there's no DI action to assist in bolt unlocking, therefor the bolt must be forced out of battery by piston operation alone In DI operation the gas pushes on the back of the bolt, in a piston, that pressure is not there causing the polt to be pulled against the barrel ext as it unlocks, causing excess bolt wear. -heavy -inherently less accurate, due to the inability to float them -there's zero standardization of parts -over-priced -Adding more (moving) parts to make a gun more reliable is ass-backwards logic. AR are designed to use DI red print is my addition. Red is mine |
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Quoted: Quoted: LMT MRP Piston uppers rock!  Im sure it does, LMT makes awesome stuff. When LMT was asked why they made piston ARs, they replied because of consumer demand. I'm, of course paraphrasing, they didn't do cause it was super amazing. Yeah, I read that too...  |
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LMT MRP Piston uppers rock! Im sure it does, LMT makes awesome stuff. When LMT was asked why they made piston ARs, they replied because of consumer demand. I'm, of course paraphrasing, they didn't do cause it was super amazing. I'm pretty uneducated on the piston platform but I do know my LMT runs and runs like a timex watch, that being said try not to flame me to bad but A. I believe the LMT MRP Piston gun has less parts and B. The AK has been in all environments and those also run like a raped ape and aren't they piston? I'm no expert and don't claim to be I know the AK is no where a accurate and so on and so forth but it's my impression that'll run no matter where or the operating conditions. Before you all jump on let me just say I'm not a proponent of the Kalishnakov family of rifles but to a laymen like myself it sure does look like he got something right. |
| I have zero interest in a piston AR. I have AKs, but that is a different animal. I have owned a couple ARs that had been absolutely neglected and had very high round counts. One of them was probably nearing the 10k round mark. As far as I know, the gas tubes had never been changed or cleaned, but they still ran. Anyone out there ever clogged a gas tube? I would guess that the pressure of the .223 round would do all of the cleaning of the gas tube by itself. I love my DIs.... I see no real 'need' for a piston AR. |
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http://www.attinderdhillon.com/wp-content/uploads/2010/03/DoubleFacePalm.jpg They both work. In my shooting of pistons(was going to buy 1) they feel different & are front heavy. For the $ I don't think they are worth it. Ditto, also, I have'nt seen piston guns give the same level of accuracy that a DGI gun gives, (and I've had the pleasure of shooting a bunch of different piston systems––thanks guys at the club!) It's not a huge difference, but there it is. If Stoner wanted the M16 to have a piston system, he would have designed the bolt carrier to have rails of some kind. Yet there are none. |
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Wow. I am new to AR's. I didn't realize I was going to strike a nerve with my question. I guess I should do some research before my next question.  It is definetly a heated issue and I think the number one reason why is because the AR15 in direct impingment has been improved upon many times over and the fact it is as combat proven and has seen as much action everyone that other "veteran" service rifles have been and yet it has earned a reputation of "not being reliable enough". We are sick of hearing that. If it was so unreliable, how did we manage to win every single battle in Vietnam with the early not-as-good models? Why has it been consistently chosen as the standard service rifle for the US military and cleaning out the competition for the last 60 years? Many people want to point to politics but anyone with a brain can tell that is BS. Did politics force over 90% of our troops to state that they are confident in their service rifle? Did politics make the Canadians adopt the Colt Diemaco? Did politics force the nation of Israel, a nation that truly and literally fights for survival everyday and is conveniently located in a part of the world that people complain that the AR cannot perform reliably, to drop their Uzis, Galils, and AK and switch them for AR15s? I think a large part of this is a misunderstanding. From what I've seen, the people who understand the direct impingment favor it. They see it for the genius that it is; simple, lightweight, self cleaning, cheap and no moving parts. That was the point of the AR15. From what I've seen from the so called "piston crowd" is a lot of them don't know that a DI system utilizes a piston, let alone how these operating systems operate. The "piston crowd" claims the "piston" is more reliable, which is convenient considering that "piston" ARs are not fielded by any military, they don't have the experience that the AR has, nor are they battle proven. It is a claim that can neither be proven nor disputed. However, it is a fact that the "piston" AR has been around for nearly as long as a DI AR, and no one wanted them then. Why the change? My guess is that perhaps the "Armalite Age" is about over and people want to move onto the next best thing, whether the next big thing is best or not. The HK416 got a huge buzz, why? Because it was new and made by H&K, therefore it must be better, right? Not. Thinking like "oh an AK is reliable and it has a piston so I'll put a piston in an AR" is like thinking that you can speed up a tank by putting a corvette engine in there, it just doesn't make any sense. IMO, for any beginner I would absolutly suggest the direct impingment for the same reasons I previously mentioned. It is simple, self cleaning, light weight, utilizes no moving parts, cheap and the fact is you will likely never need to replace the parts in the gas system. I am not "piston" hater, in fact I think the PWS system is very very cool. However, the additional costs and the limited handguard options with no real nor proven advantages just makes little sense. |
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B. The AK has been in all environments and those also run like a raped ape and aren't they piston? I'm no expert and don't claim to be I know the AK is no where a accurate and so on and so forth but it's my impression that'll run no matter where or the operating conditions. Before you all jump on let me just say I'm not a proponent of the Kalishnakov family of rifles but to a laymen like myself it sure does look like he got something right. (someone correct me if I'm wrong) well, I think comparing AK's to AR's is like comparing apples to oranges. One is made like a tank, the other is made like a rolex. The reason the AK is so reliable is that it (the original at least) has low tolerances and plenty of play. Also I dont know if you've seen a piston on an AK but they are not like the ones on AR's. Much bigger, and that I'm sure adds to the reliability. So, although yes AK's are piston, there are multiple reasons to their reliability. And as for cleaning doesnt Pat Rogers have one that hasnt been cleaned with over 30k rounds in it? just lube? |
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Pistons in ARs usually show signs of carrier tilt especially from conversion kits... ...unless you go with HK, which to my knowledge is the only manufacturer that has really created an AR piston system that functions flawlessly. HK is the only piston system I would buy personally, and I plan to get one. :D Generally though even w/o carrier tilt etc. pistons have a slower RoF and more complicated/expensive to fix, but are much more reliable and function better in harsh environments I wouldn't buy an LWRC piston AR or anything like that... if I went piston, HK only IMO. The G36 is one of the best rifles around and they moved that system (with rotating lugs) over to their HK416/MR556 etc. LWRC has addressed the issue of carrier tilt, look at the design of their bolt carrier. Looks different doesn't it? You information is beyond bad. |
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Wow. I am new to AR's. I didn't realize I was going to strike a nerve with my question. I guess I should do some research before my next question. Figgie, The only reason it strikes a nerve with everyone is becasue both sides believe stongly about the 2 designs. And there have been numerous threads about this very topic, with both sides beating eachother to death (verbally) This is also why the piston fans have their own section now. It's right below the "AR Discussion" forum. My personal opinion is that I like the piston system, but always consider myself a DI guy. |
| I have 3 osprey 416 conversions..I love them they run nice and clean and run cooler and are just as accurate as my DI carbines.With that I think the only advantage is they will run longer with no lube.If you lube a DI AR well it will ru nand run.It will run filthy and wet but not filthy and dry.I think the pistons will run filthy and dry longer.DI is still the standard and I love and will keep running both.Its nice to have cleaner and cooler runing but I would rely on either with great confidence. |
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Pistons in ARs usually show signs of carrier tilt especially from conversion kits... ...unless you go with HK, which to my knowledge is the only manufacturer that has really created an AR piston system that functions flawlessly. HK is the only piston system I would buy personally, and I plan to get one. :D Generally though even w/o carrier tilt etc. pistons have a slower RoF and more complicated/expensive to fix, but are much more reliable and function better in harsh environments Beyond all the other misinformation, "pistons have a slower RoF?" No they don't. The HK416 runs at 950-1100RPM depending on barrel length and suppressor use which contributes to many of the issues we hear about the weapon. |
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not sure about the "running cooler" bit with so-called piston designs. The heat has to go somewhere. We need mythbusters the action will be cooler as there is no hot gas dumping into it, but the chamber and bolt - the place where heat matters, will not be effected. Quoted:
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LMT MRP Piston uppers rock! Im sure it does, LMT makes awesome stuff. When LMT was asked why they made piston ARs, they replied because of consumer demand. I'm, of course paraphrasing, they didn't do cause it was super amazing. I'm pretty uneducated on the piston platform but I do know my LMT runs and runs like a timex watch, that being said try not to flame me to bad but A. I believe the LMT MRP Piston gun has less parts and B. The AK has been in all environments and those also run like a raped ape and aren't they piston? I'm no expert and don't claim to be I know the AK is no where a accurate and so on and so forth but it's my impression that'll run no matter where or the operating conditions. Before you all jump on let me just say I'm not a proponent of the Kalishnakov family of rifles but to a laymen like myself it sure does look like he got something right. AKs are not the unbreakable monsters people crack them up to be. They work better in certain environments(sometimes). Also their accuracy is much better than people who dont shoot them know(with good ammo, 2moa is not unrealistic). They are generally slightly less accurate than a standard m4, with some being more accurate. Also, the ak is a longstroke design. Gas pushes everything at once (much like an ar, but the gas hits the piston above the barrel instead of the bolt). In piston ars, almost all, if not all are short stroke designs. This means that the gas pushes a piston. The piston moves a little pushing the bolt. Piston stops and goes back foreward whilst the BCG keeps flying back. |
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Pistons in ARs usually show signs of carrier tilt especially from conversion kits... ...unless you go with HK, which to my knowledge is the only manufacturer that has really created an AR piston system that functions flawlessly. HK is the only piston system I would buy personally, and I plan to get one. :D Generally though even w/o carrier tilt etc. pistons have a slower RoF and more complicated/expensive to fix, but are much more reliable and function better in harsh environments Beyond all the other misinformation, "pistons have a slower RoF?" No they don't. The HK416 runs at 950-1100RPM depending on barrel length and suppressor use which contributes to many of the issues we hear about the weapon. In my limited experience, piston guns run faster. I have run HK, Ruger, Adams, and PWS systems on full-auto and have found that each of these will dump a 30rd mag one or two seconds faster than a 14.5" DI carbine gas system on full-auto. I think the general idea is that the extra weight and mass of the piston rod and related system parts takes longer to get moving and, therefore, slows cyclic rate. But I think it's all related to the distances that the gas has to travel. In a DI gun, the gas travels down the barrel, through the gas port and then all the way back down the gas tube to the carrier. In the average piston gun, the gas travels down the barrel, through the gas port and then onto the piston. We're really talking fractions of a second here for each cycle but do this 30 times and you can see the difference. Regarding bolt and carrier heat, I have found that the bolt and carrier (and upper as well) do stay a little cooler in the piston guns v. the DI guns. But the average shooter will not notice the difference by running a mag or two through either system. About the only way I can see piston guns having a benefit in this regard would be in continuous sustained full-auto fire. I haven't tested this theory but I'd guess the piston gun will win if you subjected both systems to something like a minute of continuous use. If someone wants to donate ammo, I'll be glad to test this theory and see what happens. 
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Pistons in ARs usually show signs of carrier tilt especially from conversion kits... ...unless you go with HK, which to my knowledge is the only manufacturer that has really created an AR piston system that functions flawlessly. HK is the only piston system I would buy personally, and I plan to get one. :D Generally though even w/o carrier tilt etc. pistons have a slower RoF and more complicated/expensive to fix, but are much more reliable and function better in harsh environments Beyond all the other misinformation, "pistons have a slower RoF?" No they don't. The HK416 runs at 950-1100RPM depending on barrel length and suppressor use which contributes to many of the issues we hear about the weapon. In my limited experience, piston guns run faster. I have run HK, Ruger, Adams, and PWS systems on full-auto and have found that each of these will dump a 30rd mag one or two seconds faster than a 14.5" DI carbine gas system on full-auto. I think the general idea is that the extra weight and mass of the piston rod and related system parts takes longer to get moving and, therefore, slows cyclic rate. But I think it's all related to the distances that the gas has to travel. In a DI gun, the gas travels down the barrel, through the gas port and then all the way back down the gas tube to the carrier. In the average piston gun, the gas travels down the barrel, through the gas port and then onto the piston. We're really talking fractions of a second here for each cycle but do this 30 times and you can see the difference. Regarding bolt and carrier heat, I have found that the bolt and carrier (and upper as well) do stay a little cooler in the piston guns v. the DI guns. But the average shooter will not notice the difference by running a mag or two through either system. About the only way I can see piston guns having a benefit in this regard would be in continuous sustained full-auto fire. I haven't tested this theory but I'd guess the piston gun will win if you subjected both systems to something like a minute of continuous use. If someone wants to donate ammo, I'll be glad to test this theory and see what happens.
So how is it the information between the two differ? The rate of fire on a DI gun is comparable if not better than the LWRC piston guns. These are specs that both Companies provided in their brochures. I want to know where you are getting your information on the high rate of fire for the HK416, LWRC, and all the other Piston guns that warrants a higher rate of fire. I did the research and it showing that DI guns have a higher cyclic rate. HK416 950-1100 rpm rate?????? Where is that info? LWRC www.lwrci.com/support/forms/OPERATORS_MANUAL.pdf Cyclic rate of fire 700 +/- 100 FPS (dependant on gas setting and ammunition) HK416 http://www.hk94.com/hk416-rifle.html Cyclic Rate of Fire - 700-900 rounds per minute. HK416 10in http://www.hkpro.com/index.php?option=com_content&view=article&id=80:hk416&catid=8:the-automatic-rifles&Itemid=5 cyclic rate of fire 700-900 RPM Colt M4A1 www.colt.com/mil/downloads/Colt_Presentation.ppt Cyclic rate of fire700-950 rpm Colt Commando Cyclic rate of fire 700-1000 rpm M16A2 Cyclic rate of fire 700-950 rpm Ruger (no information found) |
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I think the general idea is that the extra weight and mass of the piston rod and related system parts takes longer to get moving and, therefore, slows cyclic rate. But I think it's all related to the distances that the gas has to travel. In a DI gun, the gas travels down the barrel, through the gas port and then all the way back down the gas tube to the carrier. In the average piston gun, the gas travels down the barrel, through the gas port and then onto the piston. We're really talking fractions of a second here for each cycle but do this 30 times and you can see the difference. The first idea is correct, the second is not. Gas pressure in a DI system increases almost instantaneously as the gas has high pressure and little mass. By contrast, a piston has mass and therefore inertia to overcome which takes a little more time. Piston guns that are running at high cyclic rates is simply because the systems are running with too much energy and in many cases with much too short of a piston length (yes, it matters with pistons too). |
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Pistons in ARs usually show signs of carrier tilt especially from conversion kits... ...unless you go with HK, which to my knowledge is the only manufacturer that has really created an AR piston system that functions flawlessly. HK is the only piston system I would buy personally, and I plan to get one. :D Generally though even w/o carrier tilt etc. pistons have a slower RoF and more complicated/expensive to fix, but are much more reliable and function better in harsh environments Beyond all the other misinformation, "pistons have a slower RoF?" No they don't. The HK416 runs at 950-1100RPM depending on barrel length and suppressor use which contributes to many of the issues we hear about the weapon. In my limited experience, piston guns run faster. I have run HK, Ruger, Adams, and PWS systems on full-auto and have found that each of these will dump a 30rd mag one or two seconds faster than a 14.5" DI carbine gas system on full-auto. I think the general idea is that the extra weight and mass of the piston rod and related system parts takes longer to get moving and, therefore, slows cyclic rate. But I think it's all related to the distances that the gas has to travel. In a DI gun, the gas travels down the barrel, through the gas port and then all the way back down the gas tube to the carrier. In the average piston gun, the gas travels down the barrel, through the gas port and then onto the piston. We're really talking fractions of a second here for each cycle but do this 30 times and you can see the difference. Regarding bolt and carrier heat, I have found that the bolt and carrier (and upper as well) do stay a little cooler in the piston guns v. the DI guns. But the average shooter will not notice the difference by running a mag or two through either system. About the only way I can see piston guns having a benefit in this regard would be in continuous sustained full-auto fire. I haven't tested this theory but I'd guess the piston gun will win if you subjected both systems to something like a minute of continuous use. If someone wants to donate ammo, I'll be glad to test this theory and see what happens.
So how is it the information between the two differ? The rate of fire on a DI gun is comparable if not better than the LWRC piston guns. These are specs that both Companies provided in their brochures. I want to know where you are getting your information on the high rate of fire for the HK416, LWRC, and all the other Piston guns that warrants a higher rate of fire. I did the research and it showing that DI guns have a higher cyclic rate. HK416 950-1100 rpm rate?????? Where is that info? LWRC www.lwrci.com/support/forms/OPERATORS_MANUAL.pdf Cyclic rate of fire 700 +/- 100 FPS (dependant on gas setting and ammunition) HK416 http://www.hk94.com/hk416-rifle.html Cyclic Rate of Fire - 700-900 rounds per minute. HK416 10in http://www.hkpro.com/index.php?option=com_content&view=article&id=80:hk416&catid=8:the-automatic-rifles&Itemid=5 cyclic rate of fire 700-900 RPM Colt M4A1 www.colt.com/mil/downloads/Colt_Presentation.ppt Cyclic rate of fire700-950 rpm Colt Commando Cyclic rate of fire 700-1000 rpm M16A2 Cyclic rate of fire 700-950 rpm Ruger (no information found) Quoted:
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Pistons in ARs usually show signs of carrier tilt especially from conversion kits... ...unless you go with HK, which to my knowledge is the only manufacturer that has really created an AR piston system that functions flawlessly. HK is the only piston system I would buy personally, and I plan to get one. :D Generally though even w/o carrier tilt etc. pistons have a slower RoF and more complicated/expensive to fix, but are much more reliable and function better in harsh environments Beyond all the other misinformation, "pistons have a slower RoF?" No they don't. The HK416 runs at 950-1100RPM depending on barrel length and suppressor use which contributes to many of the issues we hear about the weapon. Sorry, I just wanted to quote all of this because it's definitely embarrassing to call someone out and be totally off-base. The rest of my post could be wrong; I've never heard anything bad about the 416 but I do know DI runs faster than piston. It's simple physics. To clarify, I own one AR and it's a DI Colt. I didn't say anything saying pistons were superior, but I did say that I thought the HK was the best of the piston guns, |
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Quoted:
Sorry, I just wanted to quote all of this because it's definitely embarrassing to call someone out and be totally off-base. The rest of my post could be wrong; I've never heard anything bad about the 416 but I do know DI runs faster than piston. It's simple physics. To clarify, I own one AR and it's a DI Colt. I didn't say anything saying pistons were superior, but I did say that I thought the HK was the best of the piston guns, Okay. Wow, so embarrassed. How about you check the post above yours, genius? |
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Hi to all,I cannot understand why when someone say piston Ar most of u just get angry and the hate starts,cannot understand why really.Everything made by men has it`s advantages and disadvantages.So deal with it as adults.
If anyone knows how to contact Mythbuster made they can compare the DI Colt against the H&K 416.Maybe this war will end.
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cool beans, I stand corrected. |
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