Ok so I am looking at upgrading from DGI to piston set up on my M4....

[M1911a1lvr]

I am looking to change my M4orgery to a piston setup. Who makes a decent conversion kit that won't break the bank?. I am looking at the kit Bushmaster has for sale. Does any one have any other suggestions or experience with the bushmaster kit?. looking to upgrade not buy a new rifle, That's not in the budget.

[M1911a1lvr]

I am looking to change my M4orgery to a piston setup. Who makes a decent conversion kit that won't break the bank?. I am looking at the kit Bushmaster has for sale. Does any one have any other suggestions or experience with the bushmaster kit?. looking to upgrade not buy a new rifle, That's not in the budget.

   So 38 views on this subject but no suggestions?....why not....

[JesseL]

I don't think many people have experience with them. I know I don't.

I have heard some horror stories involving things like bolt carrier tilt though.

What specific issues are you looking to resolver with a piston conversion?

[Coronach]

OK.

I'm not a gunsmith, I don't play one on TV, and it's been awhile since I have stayed at a Holiday Inn Express. That said...

Is retrofitting a piston an "upgrade?" In what sense?

I'm no Eugene Stoner/AR15 fanboy, but direct gas works. What reliability issue does adding a piston address, in your mind, and are you aware that it also causes a problem with carrier tilt and abnormal wear on the receiver extension? This is not an upside without a downside. The AR-pattern rifle was designed around direct gas, and shoehorning a piston into the mix without substantially altering other parts of the system (read: making it into a rifle that is basically not an AR anymore) isn't really a win.

IMHNGO (In My Humble Non Gunsmith Opinion), you're better off fixing whatever reliability issue your AR is currently having without adding a piston, or just starting from scratch and buying something else (FN SCAR, Sig 556, etc) that was meant to have a piston.

Mike

[Harm]

Here's what John Noveske (yeah you've heard of him right?) has to say on the matter.

http://www.defensereview.com/noveske-rifleworks-n4-light-recce-carbine-john-noveske-interview-part-one/

[DefenseReview received the following post-interview via email from John Noveske: "Also, we should mention the poor choice of platform for the piston conversion on a round receiver bore as found on the M16/M4 system. All other piston type systems out there utilize a railed receiver design, like the M14, AK-47, M249, FAL and so on. The round receiver bore design used on the M4 is only acceptable for the standard op system. The carrier and bolt expand on axis with the bore under the normal gas impingement cycle, but on a piston gun, you run into off center impulse issues with carrier tilt and incorrectly designed carrier contact points. Some designs attempt to address the carrier tilt problem with over sized carrier tails and rollers. I do not believe the receiver extension should be used in this manor. I know many people are very happy with their piston weapons. This is not meant as a knock on the piston conversion systems out there, but as a philosophical dialogue focused the new physiological relationships applied to the M16/M4 platform through the introduction of an operating system which has traditionally been applied to receivers with rails for the bolt and/or carrier. I would rather see an entirely new weapon system designed for the piston from the ground up. I believe there several outfits currently working on this."]

Emphasis added is mine. 

Sorry man I think Coronach's got a point.  If you really need a piston (I did I bought a 556 to end the debate  ) get something built from the ground up around it.  Lot of options.  Galil, FNC, Daewoo, Sig556, Aug, SCAR, ACR, AK, FAL, F2000. 

And I'll say right now you can pick up a Microtech Aug from CDNN for under a grand, and I know guys buying Sig556's for under a grand with the 300 rebate going on right now. 

[M1911a1lvr]

Here's what John Noveske (yeah you've heard of him right?) has to say on the matter.

http://www.defensereview.com/noveske-rifleworks-n4-light-recce-carbine-john-noveske-interview-part-one/

Emphasis added is mine. 

Sorry man I think Coronach's got a point.  If you really need a piston (I did I bought a 556 to end the debate  ) get something built from the ground up around it.  Lot of options.  Galil, FNC, Daewoo, Sig556, Aug, SCAR, ACR, AK, FAL, F2000. 

And I'll say right now you can pick up a Microtech Aug from CDNN for under a grand, and I know guys buying Sig556's for under a grand with the 300 rebate going on right now. 

    Well thanks for the info, I was trying to see what anyone else had for info and or suggestions. Not having any problems with my M4orgery. It is perfectly reliable. Has been for over 10 years now. I was just exploring the idea and fishing for opinions. Thanks everyone for your answers. Now on to the next topic.....move along folks nothing to see here...move along....

[Coronach]

Not having any problems with my M4orgery. It is perfectly reliable. Has been for over 10 years now.

If it ain't broke...

Seriously, I think there are a multitude of small issues inherent in shoehorning (almost literally!) a piston into a direct-gas weapon. The most obvious is carrier-tilt, and it is probably the most serious. Another issue is that you have to figure a way to run an op-rod through the very small area in the upper receiver where the gas tube would normally go. In the case of a retrofit, you LITERALLY have to run it through the gas tube hole. This results in a piston/op-rod setup that is not dimensioned "properly" for the job it has to do, but is rather dimensioned to fit where it needs to go. I have no idea whether or not this causes problems, but I have to imagine that if someone was designing a piston weapon from jump, they would not have come up with anything remotely resembling the setup of a retrofit kit. I'd chalk that up as a potential failure point, though again, I have no stats to back that opinion up.

Again, I don't think you're missing anything by not having a piston, especially since your m4gery is running like a top. The one application that MAY have you wanting to retrofit a piston is use with a suppressor, as I understand that DGI guns tend to push a lot of gas back at the shooter's face. Haven't tried it myself, though.

Mike

[Harm]

Sorry man, hope you don't feel like you just got jumped but a retro fit just seems like a bad idea. 

[HiVelSword]

Sorry man, hope you don't feel like you just got jumped but a retro fit just seems like a bad idea. 

I'm with you. I'm perfectly fine with DGI and if I want a piston rifle I'll get one that had it from the get-go.

[M1911a1lvr]

I'm with you. I'm perfectly fine with DGI and if I want a piston rifle I'll get one that had it from the get-go.

  No i don't feel like i got jumped on it. I was looking for opinions and suggestions that's all. Thanks everyone who did comment on it. I'll be leaving it the way it is.

[Bud]

I don't think any of us here have enouigh money to fire enough ammo through an M4gery for the direct gas system to reacty badly.

Most of the problems with the M16/M4 on active duty comes in sustained firefights where hugh amounts of ammo are fired without cleaning the weapon.

A piston operated system would have the advantage in that situation. I don't think the military has really thought out the retrofit arguement but then the powers that run things in the DoD have never been real good at thinking things through.

Unless you're going to go out and blow over a 1,000 rounds in a single day, I really wouldn't worry about it.
I agree with you in principle though. I will probably try to pick up an M-1 carbine from CMP just for that reason. The AK is another excellent choice but I shudder to think what my friends would say when they heard the Ak "clackityclackity clack" as you rip through a mag.

That used to be a really scary sound.

I had an M-1 carbine in VN and routinely fired hundreds of rounds through it and never once remember cleaning it other than removing the piston and letting it soak in JP4 for a while. It always fired and never missed a beat.

[tire iron]

After reading this article written by Mike Pannone (former Force Reconnnaissance Marine and former US Army Special Forces - now trainer) that the whole issue is not that the AR system needs to be run wet (I have always heard/advised/practiced the "wet" idea) - but rather the AR needs a Spring/Buffer upgrade.

He (Mike) took a bone stock NEW M4 upper - COMPLETELY removed all grease/lube/oil, etc (BONE DRY) and after a spring and buffer upgrade went on to fire over 2,400 rounds without a stoppage.......that is 80 magazines!!

He doesn't advise anyone to run their AR bone dry - he did it to prove a point that the problem is Springs and the correct buffer - not more lube.  It also proves the point that the DI method of operation is way more reliable than those on the internet would lead one to believe.

Here is a link to the article:
http://www.defensereview.com/the-big-m4-myth-fouling-caused-by-the-direct-impingement-gas-system-makes-the-m4-unreliable/

cheers

tire iron

[bmitchell]

Thanks TI - that is a great article.

Ben

[M1911a1lvr]

After reading this article written by Mike Pannone (former Force Reconnnaissance Marine and former US Army Special Forces - now trainer) that the whole issue is not that the AR system needs to be run wet (I have always heard/advised/practiced the "wet" idea) - but rather the AR needs a Spring/Buffer upgrade.

He (Mike) took a bone stock NEW M4 upper - COMPLETELY removed all grease/lube/oil, etc (BONE DRY) and after a spring and buffer upgrade went on to fire over 2,400 rounds without a stoppage.......that is 80 magazines!!

He doesn't advise anyone to run their AR bone dry - he did it to prove a point that the problem is Springs and the correct buffer - not more lube.  It also proves the point that the DI method of operation is way more reliable than those on the internet would lead one to believe.

Here is a link to the article:
http://www.defensereview.com/the-big-m4-myth-fouling-caused-by-the-direct-impingement-gas-system-makes-the-m4-unreliable/

cheers

tire iron

    Thanks TI that was a really good article. I read it and now i can really have a good reference to bring up when someone talks about the fallicies of DGI.

[tire iron]

I was glad to find it too.  My personal AR's must fire 1,000 rounds of Wolf ammo without any stoppages or maintenance before they are "keepers" - but I always lubed them up good prior to the "test".  I knew from experience that most quality built AR will pass this test.

My military experience with the AR system around the world gave me excellent results.

That is not to say I have never had a stoppage with an AR - but I have had stoppages with AK's/FN's/HK's/etc.  If a firearm is shot alot - it will experience a stoppage - that is why we train/practice our stoppage drills.

But - like you I was glad to find this because it does an excellent job of dispelling the AR internet rumors regarding the DI system and gives some proof that the piston conversions for AR's aren't needed nor necessary.

cheers

tire iron

[moose42]

I agree with you in principle though. I will probably try to pick up an M-1 carbine from CMP just for that reason. The AK is another excellent choice but I shudder to think what my friends would say when they heard the Ak "clackityclackity clack" as you rip through a mag.

That used to be a really scary sound.

So apparently this is true.

G/Sgt. Highway: This is the AK-47, the preferred weapon of the enemy. It makes a distinct sound when fired, so remember it.

-Heartbreak Ridge

[Harm]

TI - very interesting idea, that its the buffer and spring that need replacing.  Interesting.  I also found Noveske's words regarding piston upgrades to the AR intriguing about it hampering reliability.

Is anyone currently making these improved buffer and springs? 

[tire iron]

These are the mods that he suggests one do to one's AR to get it to where it needs to be:

1.  Put a Crane O-ring on the existing extractor spring

(just go to Home Depot and get this:)


2.  Use a lower receiver with a Sprinco standard Blue spring
http://www.sprinco.com/tactical.html

Item # 25007 - Tactical Springs LLC M4 / CAR-15 STD Power Moly-Plated Chrome Silicon CARBINE Buffer Spring in Hard Tube (Color Coded BLUE)

3.  H-3 buffer: A standard rifle buffer is 5.2oz. For a Carbine a standard H buffer is 3.8oz, H2 is 4.7oz and H3 is 5.6oz.)
The H-3 is commonly referred to as the "9mm buffer" by many.
http://cmmginc.secure-mall.com/shop/?cart=2328540&cat=28&keywords=&match_criteria=&rec=10&searchCat=&gonext=Next+Page

It should probably be stated that these mods are meant for rifles that are high quality to begin with - this probably won't do much for AR's that use substandard parts/assembly methods.

Hope this helps,

cheers

tire iron

[Harm]

TI - thanks for the summary. 

I actually don't own an AR yet.  Just something file away for future reference.  Hoping to add one to the stable in the near future.  And I won't buy poor quality. 

[Bud]

So apparently this is true.
-Heartbreak Ridge

It is true. I'll write another "there I was" story about the "clackityclack" sound of an AK and post it in the military thread.and post it so I don't hijack the thread.