AR-15 Piston Conversion

Discussion in 'General Firearm Discussion' started by thelendog, Apr 27, 2009.

  1. thelendog

    thelendog Member

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    Will somebody enlighten me as to why this is an improvement? Have any of you done it and changed back? Pros & Cons?

    Thanks!
  2. Trlsmn

    Trlsmn Moderator Staff Member

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    Ar15's blow dirty hot gases all over the bolt and receiver, a gas piston keeps the crap out. There are youtube videos of people doing multiple full auto mag dumps and removing the bolt and holding it in there hand. The gas piston is the best improvement to the AR15 in years, it's a shame that our military hasn't got on the bandwagon.

    A gas piston AR is definitely in my future.
  3. Unka-Boo

    Unka-Boo Active Member

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    I'm not completely sold on it, save for one exception.....shoot a suppressed AR left handed, and you'll see my point. :thumbup:
  4. RallySoob

    RallySoob Active Member

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    Some gas piston systems are great, some aren't. I would stick to DI unless you can afford an LWRC, LMT or POF pre-built gas piston upper. my .02
  5. jordanvraptor

    jordanvraptor Well-Known Member

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    My personal experience with M4's thinks this is not necessary for the vast majority of M4's let alone civilian semi-automatic rifles. Heat buildup can cause failures to extract especially when combined with lack of lubrication and sand. Large doses of CLP is the Army solution and works for the most part. A piston system is better but also adds complication and cost.

    As a civilian, I think if you want to avoid cleaning the bolt carrier group as often then by all means pay for the upgrade. If you can afford multi magazine full auto dumps, you get a big :thumbup: from me. It all depends on your style of shooting. I think I can count on one hand when my AR-15 has ever failed to fire, extract or feed. When it did it was most likely the ammo or magazine. I prefer the 20 inch old school A1 versions. :)
  6. eldbillbo

    eldbillbo Bronze Supporter Bronze Supporter

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    If you get a chance check out Kurts sight a lot of guys don't know this but he is the one that started it all his sight is down right now but when its up there is a lot of information . its too bad he did all the work in developing it and proving it could be done on a ar15 platform and now so many have ripped off the idea

    http://www.kurtskustomfirearms.citymax.com/page/page/8935.htm

    note i said on a ar15 platform the gas piston is not totally new, Eugene stoner originally developed one simular and armalite made a rifle base on that design i believe it was the ar18 then Daewoo made one simular but closer to a ak design but using many ar15 design parts then oly made one again closer to ak design just to name a few ,even though simular they were very different until the KKF design came out starting the craze cause it still looked like a ar15 type rifle

    as trisum noted and i have noted on other boards in the past this should have been designed 20 years ago by Colt or other GI contractors for our Troops

    but the DI system is cheaper and it does work if kept properly cleaned and lubercated the piston system can run longer and cooler without cleaning as unlike the DI systems which poops where it eats it poops under the handgaurds

    personally if i were to buy one it would be from KKF as you are actully paying the guy who spent the time and took the risk to develop it and not paying someone who only spent enough time to make it differrent enough so they could rip it off.

    i followed kkf as he developed this as he did not keep it a secret (he should have) but he is really just one of the guys not some big wig he like to talk about his projects as well as give helpful advice and long before a lot of other big name shops started poping up he was the go to guy.
  7. bnr32gtr

    bnr32gtr Member

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    The Military is using the piston set up, just not widely yet. Any idea how many M4's and M16's are out there to convert or replace? It all comes down to $$. I think before anyone needs to be talking piston conversion for our troops, they need to get our Men and Women a larger caliber for added insurance.

    H*ll, why not give them all space guns and phasers! Obama seems to be pulling money out of his A** for AIG but he can't divert any of the bail out to keep out troops safe and make them more effective in combat?!?!

    Whoops, got on a rant! Sorry! :D

    Anyhow, in the January or so issue of Combat Tactics there was a good article pitting the HK416, FN SCAR, Bushy XM8, Colt M4 against each other in many tests. Now, in my opinion, these outcomes can be controlled somewhat and there are so many HK416 kool aid drinkers you knew it was to be an ad for that gun. Good article none-the-less, but take it for what it's worth: advertising.

    Conversions, replacement, etc. was discussed at length and that was the best part of the article.

    Guess what I'm trying to say is, if you're in the sand box, you might want a piston driven gun. For us here running around in the woods, or at your local gun club, it's just for bragging rights. That is all.
  8. jordanvraptor

    jordanvraptor Well-Known Member

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    The gas piston conversion of an AR-15 is not a new idea. I remember seeing reviews of a company back in the 1980's. They would modify your AR-15 to piston operation. I can't remember the company's name but I found this in about five minutes of searching. It was patented in 1981...
    [​IMG]
    [​IMG]
  9. RallySoob

    RallySoob Active Member

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    fyi, military does use gas piston AR's, just not standard GI. HK416
  10. ToyotaMafia

    ToyotaMafia New Member

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    I made the switch to a gas piston after I got my first supressor. With the extra gas pressure, I was getting so much more carbon buildup in my reciever, that I saw no other choice but to convert. I did my research, looked at kits from Bushmaster, Adams Arms, PWS, and TNW. I ended up going with the TNW kit (www.tnwfirearms.com) for several reasons. 1. They a local company from Vernonia. 2. They are about half the cost of the other kits. $250 compared to $400+. And 3. because they are a long stroke piston. The difference being that the short stroke pistons rely on momentem to "hammer" the bolt carrier back. They build up speed and then impact the modified gas key. Ever used impact tools? You hit something hard enough over and over again, things will eventually break. Specifically, the screws holding your gas key onto the bold carrier. The long stroke however has the piston starting in contact with the modified gas key, and then pushing it back, rather than getting the impact action. I have had one problem with the kit, however. Unsuppressed the gun fires like a champ. 100% reliable and clean, with almost no need for any cleaning whatsoever. Suppressed though, I am actually getting so much pressre that the piston is getting pushed all the way out of the sleeve that it moves in. This only happens like 1-2 shots per mag. I have talked with the guys from TNW about the problem, and they have not heard of any other similar problems according to them. The likely problem is that I'm using a longer barrel (18"), and most people using their kit at this point are in LE, and are using 10.5" - 14.5", and thus release pressure faster than my gun and suppressor. I'm planning on SBRing my ar within the year, so it will be interesting to see the results.

    Overall, I'd say go for it and do the conversion. Piston systems are far more reliable and cleaner than standard gas operated systems, across all platforms. Well worth it in my opinion. :thumbup:
  11. RallySoob

    RallySoob Active Member

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    they can be better. but in some cases such as your own you will only be introducing more mechanical items too fail. If you were to 'need' your gun tonight and your life depended on it would you rather deal with carbon buildup or a gas piston failure?

    I've read over and over again that you should Stick to DI unless you can buy one of the seriously tested and proven systems like LWRC, LMT, or POF.
  12. ToyotaMafia

    ToyotaMafia New Member

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    That is why it sits ready to go unsuppressed, ready to go. Where it has fired 500+ rounds without a single problem.
  13. thelendog

    thelendog Member

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    Don't get in an argument over little ol' me! :paranoid:

    Thanks for all the input! :thumbup:
  14. RallySoob

    RallySoob Active Member

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    :poke:

    n/m