I've changed my opinion on piston driven rifles.

[JaPes]

I've changed my mind about piston driven rifles in general, and my opinion that AR-15's should all be DI just as Eugene Stoner intended. Why the change? Got back from shooting my Tavor at the range. Cleaning a rifle that doesn't poop where it eats is so much faster and easier.

I'm considering converting my home built AR from DI to piston driven.

 

[Rick_A]

Meh. Gas guns wipe down pretty quick. Just like the piston/cup in a piston gun, the carrier gas chamber and bolt tail don't have to be spotless. A little time soaking in lube works if you're bent on having it white glove clean.

Either way is preference.

Simple is good.

 

[Rastoff]

Hmmm, I'm not convinced that it's an improvement.

Does the hand guard get hot up by the gas block? Do you end up with a lot of carbon build up there as well?

 

[oberon]

Stoner's gun is ok with me.
It was designed the way for a reason.
A couple reasons, actually.

 

[JaPes]

All I'm saying guys is that I used to say all the things you guys just said. I didn't think a gas piston system could be an improvement. I was a DI die-hard. There are a few guys on this board who converted their M&P 15's from DI to piston driven. I gave them the knee jerk, DI is better.

Hmmm, I'm not convinced that it's an improvement.

Does the hand guard get hot up by the gas block? Do you end up with a lot of carbon build up there as well?

In the Tavor, it does get warm but not hot. It's a long stroke gas piston. All I have to wipe off is the piston, not the gas block. It cleans up real quick. The layout is very reminiscent of an AK and appears to be robust.

All I'm saying is that don't discount a gas piston system. During the worst part of winter when I'm stuck indoors, I'll install a short stroke gas piston conversion on my home built Franken AR-15.

DI has it's advantages. Piston has it's advantages too.

 

[Rastoff]

I've never discounted either one. As I see it, they are almost the same. The only real difference is where the gas pushes. One pushes at the gas block and the other pushes on the bolt.

The advantage of the piston is that the carbon is kept away from the bolt.

I can't imagine one is more reliable than the other.

 

[rojodiablo]

I've never discounted either one. As I see it, they are almost the same. The only real difference is where the gas pushes. One pushes at the gas block and the other pushes on the bolt.

The advantage of the piston is that the carbon is kept away from the bolt.

I can't imagine one is more reliable than the other.

The one true benefit is when using the rifle in a very wet environment. We had them dunked, and they had to come up firing. Boy, did we train ourselves how to clear that chamber a little bit to ensure if it were ever needed, we would not be creating a single-shot rifle in the middle of a turdstorm.

Other than that- cleaning is a non-issue. Yeah, with use they get dirty. Spray cleaner/ spray lube will carry them for months and months. A soak in solvent will get the BCG clean when you have time to let it soak and then scrub it out. But really; they WILL run wet (Swampwater) dirty (Swampmud, sand, etc.) and they will run UGLY (Dropped, buried in junk, cracked furniture, etc.)
I like piston rigs well enough, but not enough to spend money to swap them.

 

[MichiganScott]

One more vote against pistons. They are an answer in search of a problem. Stoner got it right.

 

[spad124]

All I'm saying guys is that I used to say all the things you guys just said. I didn't think a gas piston system could be an improvement. I was a DI die-hard. There are a few guys on this board who converted their M&P 15's from DI to piston driven. I gave them the knee jerk, DI is better.



In the Tavor, it does get warm but not hot. It's a long stroke gas piston. All I have to wipe off is the piston, not the gas block. It cleans up real quick. The layout is very reminiscent of an AK and appears to be robust.

All I'm saying is that don't discount a gas piston system. During the worst part of winter when I'm stuck indoors, I'll install a short stroke gas piston conversion on my home built Franken AR-15.

DI has it's advantages. Piston has it's advantages too.

I think some of it has to do with the ammo from the era when the rifle was designed. The AR was designed for ammo that was not corrosively primed. It doesn't matter if the primer fouling sits on the bolt for a while. (The 30 Carbine M1 also is designed to be used with non-corrosive ammo. Special tools are needed to take the piston out. The issued carbine ammo was non-corrosive even in WWII).

On the other hand, the AK, and it's parent, the SKS (which I have in addition to my Sport) were designed to be used with corrosive ammo by keeping the corrosive gasses away from the bolt.

Either system works. I suspect Stoner was trying to simplify and to take advantage of non-corrosive ammo.

 

[Arik]

I don't think DI is better, nor worse. It's just a different form of function. My AR is DI just because it is but I wouldn't have a problem with one that's a piston driven since everything else I own is piston. The only thing I would add is that be careful about the drop in pistons. A lot of them wear heavily on the receiver. If I were to buy a piston AR it would be one that was built from the ground up as a piston AR. Google carrier tilt

 

[Arik]

I think some of it has to do with the ammo from the era when the rifle was designed. The AR was designed for ammo that was not corrosively primed. It doesn't matter if the primer fouling sits on the bolt for a while. (The 30 Carbine M1 also is designed to be used with non-corrosive ammo. Special tools are needed to take the piston out. The issued carbine ammo was non-corrosive even in WWII).

On the other hand, the AK, and it's parent, the SKS (which I have in addition to my Sport) were designed to be used with corrosive ammo by keeping the corrosive gasses away from the bolt.

Either system works. I suspect Stoner was trying to simplify and to take advantage of non-corrosive ammo.

I doubt it has anything to do with corrosive ammo. DI has been used by other countries and long before there was non corrosive ammo.

Corrosiveness is In the primer. So once the firing pin hits the primer you get corrosive salts on the bolt and without cleaning the bolt and the receiver will start to corrode overtime. It's not uncommon to get corroded firing pins in used AKs. Neither is one a parent of the other. It's was 2 different rifles with different design ideas.

 

[A.O.]

Just a quick vote for the piston.. only because the gun stays a lot cleaner. My Scar is heads and tails cleaner than my Colt Competition was..

 

[Lee in Quartzsite]

Pick up any gun magazine and you will see ads from major manufacturers that now have a piston version in their inventory. The arguments against a piston gun are usually made by people who have never even shot one, much less cleaned one. The added weight comments make me chuckle because the weight of my piston assembly weighs a whole whopping 6 Ounces...much less than added lights, lasers, or Bi-pods that clutter today's rifles. I can thoroughly clean my M&P 15PS in less than 15 minutes. My gun is now 3 1/2 years old and never malfunctioned in any way. As long as they both go Bang, who cares?

Same arguments were made years ago when the first automatic transmissions first came out....people said they were junk and would never last.

 

[BlueOvalBandit]

Good news! AR-15s are piston systems without the operating rod! Everyone wins!


Ok, I'm done.

 

[Woodman90]

I'm a long stroke piston fan. PWS makes an excellent product. I like being able to adjust the gas quickly for going between suppressed and unsuppressed. Yes DI rifles can have an adjustable gas block I'm aware of that. They do run cleaner too. I can run 500 rounds suppressed through my piston sbr without cleaning and zero malfunctions. For those that don't shoot suppressed it will get dirty much quicker. It is nice to take a carbine class and watch others cleaning their rifles before the day is over. I don't mind cleaning, but I'd rather spend my time putting rounds downrange.

 

[Maximumbob54]

I just know I didn't care until I bought a piston upper just because it was a crazy sale. Now I hardly ever shoot the DI one. I did just buy a 6.8 upper and plan on dropping in a piston package into that one as well.

 

[Rastoff]

I like being able to adjust the gas quickly for going between suppressed and unsuppressed.

Do you change out your suppressor a lot? I know I don't. Then again, if I'm too cheap to buy a piston conversion, I'm way to cheap to jump through the government's "Mother May I" program to get a suppressor.

 

[rojodiablo]

Do you change out your suppressor a lot? I know I don't. Then again, if I'm too cheap to buy a piston conversion, I'm way to cheap to jump through the government's "Mother May I" program to get a suppressor.

And, given our location (PRK)....... the only way I make my rifle quieter is by shooting it in an outhouse.

 

[jaymoore]

I like piston ARs when a suppressor is used. Especially in select fire. (First experienced the difference when invited to a shoot with a couple of H&K reps returning from a demo at Ft. Benning. We brought "old school" and they brought their newest!) Otherwise, have not felt the need.

BTW, Stoner wasn't against the piston design. Prime example? The "low tech" (i.e. easier to manufacture) AR18/180. That design never really left the starting gate due to lack of sales. Only real weak point in that 1960's design was the stock's hinge and lock, so....

 

[Woodman90]

Do you change out your suppressor a lot? I know I don't. Then again, if I'm too cheap to buy a piston conversion, I'm way to cheap to jump through the government's "Mother May I" program to get a suppressor.

Not a lot, but I have only one 30 cal can and more hosts than I care to mention. Each has a fast attach muzzle device, so really I just move the can from host to host depending on what I'm wanting to shoot and the rifle may have been previously setup for non suppressed so I need to change the gas.