Adams Arms Piston Kits/Voodoo Innovations barrels?

[Gaspipeshooter]

Anyone have any experience with the Adams Arms piston kits? Considering a piston kit and 11.5" barrel for my pistol build.

[UWone77]

I have a Voodoo/AA kit, but haven't installed it yet.

Why do you want to go with a piston kit? Especially on a 11.5? Frankly, I am less than impressed with the AA Kits. One of the two kits I used, the op rod was stuck at the 500-600 round mark. No amount of lube, kroil, tapping with a mallet would get it loose. The only piston I would consider at this point based on experience is the PWS.

[gatordev]

I built a 11.5" upper with a Mega-branded AA kit and have had a good experience with mine. This particular one was made to fit Mega monolithic uppers, which is why it's branded Mega, but it's still an AA kit. I have just over 1000 rounds on mine and the two issues I initially had was getting the bushing for the rod into the receiver (it was really tight), which made it hard to get it even. This in turn made the rod rub and not operate completely freely. Once I took a few more whacks at the bushing and made it even in the upper, everything lined up and there was no more rubbing. I've had zero carrier tilt issues on mine.

All that said, I built it to see what an Op Rod gun was all about first hand rather than reading about how it was 100% concentrated evil on the internet. I'm glad I built it, but I'm not convinced it's really doing anything better than my DI guns other than shooting with almost no recoil impulse when it's suppressed. I'll keep the one I have, but I don't really plan on building or buying another one.

What UWone describes sounds like the bushing or gas block got out of alignment, though I'm sure he troubleshot that, so maybe it was something else.

[Gaspipeshooter]

I have a Voodoo/AA kit, but haven't installed it yet.

Why do you want to go with a piston kit? Especially on a 11.5? Frankly, I am less than impressed with the AA Kits. One of the two kits I used, the op rod was stuck at the 500-600 round mark. No amount of lube, kroil, tapping with a mallet would get it loose. The only piston I would consider at this point based on experience is the PWS.

My thoughts on a piston kit would be to be able to adjust the gas when suppressed. That was my primary consideration.

[UWone77]

My thoughts on a piston kit would be to be able to adjust the gas when suppressed. That was my primary consideration.

Yeah, that was my original plan too. But my gas plug on one of my AA uppers is stuck on the non-suppressed/"normal" position. Won't budge. I guess I won't be shooting this suppressed!!

[WHSmithIV]

I don't have experience with one 'yet'. However, I just won the one I designed in the Gunstruction design competition. I'll let you know what I think about it after it arrives :)

[Gaspipeshooter]

I don't have experience with one 'yet'. However, I just won the one I designed in the Gunstruction design competition. I'll let you know what I think about it after it arrives :)

Mine is sitting on the bench; 5.56 - 11.5" Voodoo Innovations medium contour barrel and the Adams Arms piston kit. I've got the lower all ready to go, including the Sig Tac pistol brace. Just need a handguard and muzzle device to be operational.

[Swatbwana]

My thoughts on a piston kit would be to be able to adjust the gas when suppressed. That was my primary consideration.

I used an AA kit on a DD 10.5 barrel with the DD 9.5 FSB rail works excellent suppressed .

And runs like a beast on a registered lower as well.


Sent from my iPad using Tapatalk HD

[Gaspipeshooter]

I used an AA kit on a DD 10.5 barrel with the DD 9.5 FSB rail works excellent suppressed .

And runs like a beast on a registered lower as well.


Sent from my iPad using Tapatalk HD

Good to know you have had a good experience with yours. I need to quit waffling and decide on a handguard and muzzle device so I can wrap mine up!

[Hmac]

I'm looking for a good, lightweight melonite-coated barrel. I live right here at Huldra HQ and the principles of the company are guys that I shoot with regularly. The Adams Arms barrels (and I presume Voodoo Innovations) have served them very well from a longevity and reliability standpoint and I'm thinking that's the direction I'm going to go. Sionics is interesting, and cheap, but in the absence of any longevity info I'm going to pass. Apparently, not all melonite-coated barrels are created equal.

[Gaspipeshooter]

Well, other than a muzzle device and a handguard, my piston pistol build is ready to go.



I order my handguard from Midwest Industries yesterday, still trying to decide on a muzzle device. I may throw an A2 birdcage on there for now and see how she runs. Grip and FCG are temporary as I had them laying around. Thinking an ALG ACT FCG and maybe an Umbrella 23 grip...

[WHSmithIV]

Folks the technical nitty gritty of this is pretty simple. The barrel is fine - Yes, the Voodoo barrels are a bit expensive. The barrel though isn't really the question. Any reasonably decent melonite or nitride barrel will basically last as long, be as accurate and functionally equivalent.

It is the piston system that is the question though.

Let's take a walk down memory lane for a moment. The M16 was designed back in the 1960's. There is even a photograph of President Kennedy holding one of the first prototypes. (I'm guessing if such a picture would be taken today it would be Obama holding a golf club and smoking a joint) Sorry folks I just couldn't resist that one in the context of what I'm writing.

The M16 was a fully automatic machine gun. Select fire 3 round burst did not exist then yet. The M16 was full auto or single shot semi auto - that's it.

The M16 was also marketed to good old Joe public USA. The full auto function was removed (it is a trigger group part only anyway) and Joe Public Citizen now had the same new technology rifle that our Army had adopted. That's a good thing too. Because it is ultimately Joe Public Citizen who would have to be called upon to defend our USA from invasion and the M16 / AR15 is very good rifle.

So, fast forward 35 years. What was the worst problem of the 1960's design? The design is pure genius and very simple, but, it does have a problem. The M16 or AR 15 uses the burning fumes from the explosion in the cartridge to fire the bullet to also reload itself. Those burning gasses do have carbon and that and carbon is an element that will build up in a very short time. Our Viet Nam vets were told they would never have to clean the rifle and what they found out was that their very lives depended on keeping it VERY clean daily.

So, fast forward another 40 years. Someone understood the fouling problem from the gas operation, so a piston driven - still gas fired - design was invented. This is VERY helpful with keeping all that nasty carbon after burned gas fouling crap from going back into the upper receiver and to ultimately the bolt and firing pin. However, that still is the same gas that drives the semi automatic function. On the plus side though, you don't have to take apart he entire rifle to clean the carbon fouling from firing gunpowder. With a piston system no gasses go back into the receiver so all the fouling is localized in the gas block. That does make sense, but it does add extra mechanical parts. It also brings up the question as to how easy it is to clean that block that's driving the piston.

There is a secondary effect of using a piston instead of the gas to move the bolt carrier back to cycle the action. Gas expands equally in all directions. A mechanical rod doesn't. The physical movement of the rod puts unequal pressure on a bolt carrier and that does lead to extra wear in an upper receiver.

[Gaspipeshooter]

From a physics/mechanics point of view, the gas key and gas tube contain the gases until the BCG has moved far enough rearward to separate. The pressure exerted on the BCG by either gas or a piston rod is concentrated in basically the same area. I don't have first hand experience with a piston set up, (yet!), but it seems to me there should not be a tremendous amount of difference in BCG tilt.

As for cleaning, I'm thinking from what I have seen so far I'd much rather clean the gas block and piston. I know it is comparing apples & oranges, but having run 10s of 1,000s of rounds through Remington 1100s and 11-87s in my trapshooting days as well as waterfowl hunting, I learned something from that experience that I will apply to the piston set up. I ran, (and still do run) my Remingtons "wet", that is with liberal amounts of Breakfree CLP applied to the gas system parts. The carbon is essentially held in suspension, and for the most part wipes right off. I'll be trying that on the piston system to see how it works.

[Gaspipeshooter]

Finished product at the "functional stage". The pistol grip, FCG, and muzzle device will get changed eventually, but at least I can run some ammo through it now.



The handguard and piston gas block:

[Gaspipeshooter]

I got a chance to stop by the range this afternoon and give the pistol a quick function check. I was very pleased with it. I only ran two 30 round mags through it, but on measured firing and rapid fire it ran very smoothly. Now to decide on a sight...