Gas vs Piston

[titaniumdoctor]

I'm in the market for a precision AR platform, and been a long time fan of JP rifles....specifically the CTR and LRP. I looked at the POF P308 FDE at SHOT last year and was impressed with that gun as well. knowing that the JP is a gas gun and the POF is a piston platform, should I go with the JP for long range shooting? I'm new to the AR scene and I am looking at ordering a gun at SHOT this year. Any input would be appreciated.....

 

[FRO516BMX]

Re: Gas vs Piston

While not a direct answer to your question, since I am not as tech savvy as most here, this should at least give you the majority of the info your looking for.

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1863890

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2502645&page=1

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2809430

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1723095

Also the Snipers Hide search engine will help as well. Unfortunately I cant get the link to work, I'm sure someone will post it up for you. Hope this helps.

 

[kraigWY]

Re: Gas vs Piston

The Piston AR is the perfect solution to a non-exsistant problem.

 

[Killbox Alpha]

Re: Gas vs Piston

I know this is alot lower on the food chain than the POF or a JP rifle but my Ruger SR556 runs cool, even after rapid fire situations in the heat of the summer. Now if we could only get Ruger to put a 1 and 8 twist on them instead of the 1 and 9's

 

[USACS]

Re: Gas vs Piston

This topic has been covered ad-nauseum in multiple formats. It's been documented that DI guns are capable of better accuracy, but the piston guns are still very accurate.
If you are considering a JP, I would offer these thoughts- JP rifles are basically benchrest/target/varmint rifles or 3-gun/steel challenge/action arms rifles. They have a the JP-15 line, but it's excessively over-priced IMO.
Given that your price range would likely be in the $2500 range if you're considering a POF, I would also look at the LWRC REPR for piston rifles, and the DI rifles like the LaRue OBR, GA Precision GAP-10, LMT MWS and Noveske N4.

 

[ChielScape]

Re: Gas vs Piston

If you get an AR, get a DI. The platform is not designed for pistons, introducing things like carrier tilt.
There are 1 or two specialized designs that overcome this with internal rails for the bolt to ride on, like the ADCOR BEAR, so if you want a piston gun seek out these specific rifles.

 

[Chucky]

Re: Gas vs Piston

Also something to consider is if you do decide to go the suppressor route a lot of times piston guns have much larger shifts than the DI guns. I just ran around 1K rounds through my OBR both suppressed and unsuppressed on Saturday and I lubed it once halfway through and the gun ran. There are pics of it in the suppressor forum.

 

[turbo54]

Re: Gas vs Piston

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: kraigWY</div><div class="ubbcode-body">The Piston AR is the perfect solution to a non-exsistant problem. </div></div>

You nailed it!

I bought into the piston craze and bought a Ruger SR556. It's a good rifle, but it balances poorly and is HEAVY. You really notice it when you're at a tactical match where one of the stage scenarios is your strong side arm is "injured" and of no use to you... I literally DNF'd that stage because I couldn't support my rifle long enough with my weak side.

Sure, the bolt carrier stays cleaner, but who cares?

 

[152]

Re: Gas vs Piston

I know so little on this subject and have wondered my self.

I have been told by class3 shooters,or full auto guys,that unless you are dumping several thousand rds in a very short period of time the gas piston is a waste.

The info here on accuracey is good.Concerning this topic.

 

[jakhamr81]

Re: Gas vs Piston

Don't forget the recoil. The piston. Guns I have shot seem to have a sharp punch of a recoil that can jar your whole face. I found follow up shots to be more difficult.

 

[gvanhyning]

Re: Gas vs Piston

I have the Bushmaster M4A3 with gas piston and I think it's great. The big plus is no carbon in the upper receiver. The piston on mine is reversible with different sized gas ports.

 

[DernHumpus]

Re: Gas vs Piston

I have no problems with my DI guns. Will not consider changing to a different platform nor buying uppers that use a piston system.

 

[KillShot]

Re: Gas vs Piston

I love my piston P308 but I wouldn't hesitate to get a GAP, LMT, BCM, or other quality DI system. In fact, that's what I plan to do in the next 6 months.

 

[Conrad101st]

Re: Gas vs Piston

Killshot,

Why so? I think your rig is good to go. Nice setup. Why duplicate the same basic platform?

Conrad

 

[jhart2424]

Re: Gas vs Piston

Never had problems with DI. Its simple, to the point and no extra parts. I dont buy pre built AR's, so for me I would build one up for your "specs" and not what a manufacture thinks you want. With that said, the LWRC and GAP AR's are GTG!!

 

[MD2Colo]

Re: Gas vs Piston

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DernHumpus</div><div class="ubbcode-body">I have no problems with my DI guns. Will not consider changing to a different platform nor buying uppers that use a piston system. </div></div>

right there with ya.

Don't have much experience with piston ARs, but I'm not sure I'd be comfortable running a gun that moves the heat from the receiver to my left hand... it's already hot enough up there as it is, in my humble opinion. DI is my personal preference.

 

[rcw3]

Re: Gas vs Piston

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Titaniumdoctor</div><div class="ubbcode-body">I'm in the market for a precision AR platform . . . Any input would be appreciated..... </div></div>

For precision and accuracy, a piston system is never an advantage over the traditional DI gas system. A piston system has moving parts that are connected (directly or indirectly) to the barrel assembly that impart impulses, vibration and forces to the barrel as the shot is in the bore, all of which can sabotage accuracy.

 

[K_4c]

Re: Gas vs Piston

That's funny... My REPR was a solid MOA set up. I love the fact that they don't shit where they eat. Regardless, a quality DI will run and run well.

 

[deadly0311]

Re: Gas vs Piston

The only piston gun that I would ever consider owing in an assault rifle platform is the G36, its not like traditional pistons where the recoil punch is sharp and the parts are proprietary. Direct Impingement guns run just fine, the piston like Kraig said, the piston is a solution searching for a problem.

 

[tim3gun]

Re: Gas vs Piston

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">For precision and accuracy, a piston system is never an advantage over the traditional DI gas system. A piston system has moving parts that are connected (directly or indirectly) to the barrel assembly that impart impulses, vibration and forces to the barrel as the shot is in the bore, all of which can sabotage accuracy. </div></div>
Is that why the M14/M1A is inaccurate ? I'm calling shinanigans on DI guns being more accurate. I think it depends on whos barrels and ammo is being used along with field conditions and the shooter himself.

 

[Strangedays]

Re: Gas vs Piston

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Tim3gun</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">For precision and accuracy, a piston system is never an advantage over the traditional DI gas system. A piston system has moving parts that are connected (directly or indirectly) to the barrel assembly that impart impulses, vibration and forces to the barrel as the shot is in the bore, all of which can sabotage accuracy. </div></div>
Is that why the M14/M1A is inaccurate ? I'm calling shinanigans on DI guns being more accurate. I think it depends on whos barrels and ammo is being used along with field conditions and the shooter himself.
</div></div>
Like Tim said, but it would cost much more to make a nice M14 or M1A than a AR platform. Shooter is most of the time the biggest accuracy sabotage out in the field. I have seen POFs shoot under 1/2 MOA from the factory with no special things done. I have had no such accuracy from DI guns from the factory. I build all my ARs (Put the legos together) and get 1/2 moa on all of them.

 

[adam1122]

Re: Gas vs Piston

This may be one of the most overdone subjects on the hide. DI vs piston accuracy is a pretty much non-existent arguement so long as you compare two quality rifles. The operate slightly differently. I own both and I will say the piston's biggest benifit is it take about 10 minutes to clean so if you shoot alot its worth a look.

MY LWRC can also be shot with the gas turned off....so anyone who wants to debate the accuracy of an LWRC gas piston system I'd love to see a standard M4 piston gun outshoot straight one of these piston guns out of the box.

It's more training than equipment that leads to accuracy.

 

[KillShot]

Re: Gas vs Piston

Well stated, SteelShot11. I am in total agreement with you. Although I've not done it myself, the POF rifles also have the option of turning the gas off entirely.

 

[steve_of_AR]

Re: Gas vs Piston

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Is that why the M14/M1A is inaccurate ? </div></div>

Talk to anyone on the AMU teams who used to run M14's in national matches. They had to be constantly rebuilt to keep them accurate. The M16's were just easier.

 

[jakhamr81]

Re: Gas vs Piston

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KillShot</div><div class="ubbcode-body">Well stated, SteelShot11. I am in total agreement with you. Although I've not done it myself, the POF rifles also have the option of turning the gas off entirely. </div></div>

As do many DI guns with adjustable gas blocks. Shutting off the gas is not a feature exclusive to piston guns.

 

[rpk762]

Re: Gas vs Piston

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SteveAR</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Is that why the M14/M1A is inaccurate ? </div></div>

Talk to anyone on the AMU teams who used to run M14's in national matches. They had to be constantly rebuilt to keep them accurate. The M16's were just easier.</div></div>

That is why the USMC dumped all of the new M1A rifles they purchased for the SAMR.

 

[Snipers]

Re: Gas vs Piston

In theory, DI is more accurate and piston more reliable. However, the quality of the individual weapon is most important. I believe the piston allows for a cleaner, cooler, lubed action resulting in improved reliability in adverse conditions (such as extreme heat). This would be magnified during full auto. DI has less moving parts and associated vibration that can impact barrel harmonics.

I have owed both DI and piston guns. Personally, I would lean to DI for match/competition and piston for combat, but either can effectively fulfill both rolls.

 

[GoldnGun]

Re: Gas vs Piston

I converted my AR15 SBR to gas piston with an Adams conversion kit. I love it. Excellent with or without a supressor. I run a YHM Phantom with Extreme Shock subsonic ammo with incredible results. Cycles the action perfectly and is as quiet as a supressed .22!! Accurate also...)

 

[Sebben]

Re: Gas vs Piston

Lowlight compared the POF P308 to a GAP-10 and he said his POF was a half MOA gun and the GAP was 3/8th MOA gun. It's to the point where it doesn't really matter in terms of accuracy. Piston and DI are just different tools for different jobs. piston really only separates it's self from DI when it comes to sustained full auto fire. With DI you get melted gas tubes and you reach cook off faster.

 

[rcw3]

Re: Gas vs Piston

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Tim3gun</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">For precision and accuracy, a piston system is never an advantage over the traditional DI gas system. A piston system has moving parts that are connected (directly or indirectly) to the barrel assembly that impart impulses, vibration and forces to the barrel as the shot is in the bore, all of which can sabotage accuracy. </div></div>
Is that why the M14/M1A is inaccurate ? I'm calling shinanigans on DI guns being more accurate. I think it depends on whos barrels and ammo is being used along with field conditions and the shooter himself.
</div></div>

You won't see virtually anyone finishing in the top spots of the major high power matches shooting an M14/M1A these days. I shot them for years in high power competition and the AR's I build now can destroy the M14/M1A's (even the highly customized and accurized ones I had) in terms of consistent and tight accuracy - not even a close call there. The piston system was not an accuracy based semi auto system from the get go and was never designed as such, and is not being employed for that reason now on rifles. The M14/M1A is fun to shoot and you can do reasonably well with it but it's a little like a vintage muscle car, fun to drive but not exactly competitive for real racing.

 

[kaptain86]

Re: Gas vs Piston

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: kraigWY</div><div class="ubbcode-body">The Piston AR is the perfect solution to a non-exsistant problem. </div></div>

Hahaha, do you think a lot more companies will try and go to only piston style even though its not needed?

 

[snipe10]

Re: Gas vs Piston

well said