I am in the process purchasing a 6.8 upper for weekend shooting and possible home defense i have an (870) filling that role at the moment. How often do gas rings fail as far a fouling i like cleaning my guns after a trip to the range, is the increased price for a piston upper really worth it? Question two what kind of accuracy are you guys achieving at 100yds with a 16" barrel.
joa coastie
I recently purchased the LMT Piston upper and the accuracy is on par with the DI. Here is my review on it. You can debate the DI vs Piston thing all day, but in the end it is going to be your choice. They both work well and will definitely work well for your purposes. If you have the extra cash and don't want to mess with the extra cleaning, get the Piston. If you don't want to spedn the extra cash and/or you don't mind the cleaning, get a DI. In the end, you have to make the final decision.
There are 2 main types of ARs around.
Type 1 is the original Direct Impingement gas operated Rifle, as originally designed by Mr. Stoner way back in the day. When you pull the trigger, a round is fired, sending a bullet down the chamber, as well as expelling gases. Once the bullet passes the hole in the barrel where the gas block is located, pressurized gasses travel into the gas block, down the gas tube and back towards the receiver. Once it goes into the receiver it hits the Bolt carrier group and the gas key, and due to pressure, the BCG travells back and the sprind in the buffer tube pushes it foward where is pick up another round and prepares to fire again
Type 2 is a gas piston rifle. Very similar to that of an AK-47. Several AR manufacturers utilyze the piston system, encluding the AR-1 from ARP, Addax Tactical, POF USA and I believe Barrett. In a Piston system, When you pull the trigger, a round is fired, sending a bullet down the chamber, as well as expelling gases. Once the bullet passes the hole in the barrel where the gas block is located, pressurized gasses travel into the gas block, and due to pressure, push a piston back towards the upper receiver. The piston hits the Bolt carrier group and the gas key, and due to pressure, the BCG travells back and the spring in the buffer tube pushes it foward where it picks up another round and prepares to fire again.
Advantages of each.
Direct Impingment:
Cheaper! Most piston uppers go for at least 1500 while a DI upper can be had for 500.
Accurate. Most argue that DI is more accurate than piston systems, although that is a debate. Most pistons seem to shoot around 1-5 MOA(mites of Angle) depending on quality, whereas DI uppers can go below .5 MOA.
Interchangability. DI parts from almost every DI upper can be interchangable. Bushmaster parts work on DPMS uppers, etc etc etc
Piston:
Cleaner! Since gases arent returned into the upper via the gas tube, you dont get a lot of carbon buildup in the action area. You wont have to clean a piston upper near as much, and therefor, should actually last a little longer than a DI gun
Heat. Since pistons dont get the gas blow back, the inner parts stay cooler, which would also make the parts of the gun last longer.
As a review, msot aruge that you dont need a piston gun unless you shoot at least 2K rounds a month. If you only shoot a couple hundred a month, and take good care of the rifle, a DI upper should last longer than you!
Edit: this is a reply that I posted in a thread a few weeks ago, might not cover your questions exactly, but might shed a little insight
Type 1 is the original Direct Impingement gas operated Rifle, as originally designed by Mr. Stoner way back in the day. When you pull the trigger, a round is fired, sending a bullet down the chamber, as well as expelling gases. Once the bullet passes the hole in the barrel where the gas block is located, pressurized gasses travel into the gas block, down the gas tube and back towards the receiver. Once it goes into the receiver it hits the Bolt carrier group and the gas key, and due to pressure, the BCG travells back and the sprind in the buffer tube pushes it foward where is pick up another round and prepares to fire again
Type 2 is a gas piston rifle. Very similar to that of an AK-47. Several AR manufacturers utilyze the piston system, encluding the AR-1 from ARP, Addax Tactical, POF USA and I believe Barrett. In a Piston system, When you pull the trigger, a round is fired, sending a bullet down the chamber, as well as expelling gases. Once the bullet passes the hole in the barrel where the gas block is located, pressurized gasses travel into the gas block, and due to pressure, push a piston back towards the upper receiver. The piston hits the Bolt carrier group and the gas key, and due to pressure, the BCG travells back and the spring in the buffer tube pushes it foward where it picks up another round and prepares to fire again.
Advantages of each.
Direct Impingment:
Cheaper! Most piston uppers go for at least 1500 while a DI upper can be had for 500.
Accurate. Most argue that DI is more accurate than piston systems, although that is a debate. Most pistons seem to shoot around 1-5 MOA(mites of Angle) depending on quality, whereas DI uppers can go below .5 MOA.
Interchangability. DI parts from almost every DI upper can be interchangable. Bushmaster parts work on DPMS uppers, etc etc etc
Piston:
Cleaner! Since gases arent returned into the upper via the gas tube, you dont get a lot of carbon buildup in the action area. You wont have to clean a piston upper near as much, and therefor, should actually last a little longer than a DI gun
Heat. Since pistons dont get the gas blow back, the inner parts stay cooler, which would also make the parts of the gun last longer.
As a review, msot aruge that you dont need a piston gun unless you shoot at least 2K rounds a month. If you only shoot a couple hundred a month, and take good care of the rifle, a DI upper should last longer than you!
Edit: this is a reply that I posted in a thread a few weeks ago, might not cover your questions exactly, but might shed a little insight
For the vast majority of shooters, there will be no noticeable differences between the two. Buy the good brands of either system and you are set. DI's don't gunk up and stop running after a magazine like some "experts" claim.
I was watching Future Weapons the other day, and the new British 50 cal sniper rifle is DI. So apparently DI is still viable afterall.
Really it comes down to buying the best you can and taking care of it. I bet many LWRC owners on this site are still cleaning their piston rifles even with the piston upper. I know I would still clean a rifle, piston or DI. Then I've read posts where well known shooters just keep their DI guns lubed and don't worry about fanatical cleaning until thousands of rounds have been fired.
I was watching Future Weapons the other day, and the new British 50 cal sniper rifle is DI. So apparently DI is still viable afterall.
Really it comes down to buying the best you can and taking care of it. I bet many LWRC owners on this site are still cleaning their piston rifles even with the piston upper. I know I would still clean a rifle, piston or DI. Then I've read posts where well known shooters just keep their DI guns lubed and don't worry about fanatical cleaning until thousands of rounds have been fired.
Hah!! See... RCrandall has all the nice toys.. LWRC's, Colt Commandos. He never misses a piston v DI debate either!! :lol: :lol:rcrandall said:
Notice he mentions the cleaning time between the two? Good point.
You are well armed with either system if they are from a reliable manufacturer like Colt, LWRC and others.
CMMG posted in ARFCOM they plan to offer a piston upgrade at time of rifle/upper purchase for a net increase around $100. They are keeping the price down by avoiding duplication of parts some encounter when they convert a DI to Piston. If their system proves reliable, this could be the best bargain in AR piston uppers.
Apparently SW has. Looks like their new M&P15 piston upper is an Adams Arms unit.coldair said:
Tim_W looked into Adams maybe he'll be here sometime today. I researched them and they seem to be one of the good systems. They have a post that 10-8 or someone like that is working on an Adams Arms based 6.8 upper on ARFCOM.
I'd lean towards ADDAX's PWS since they already have 6.8's running, not to mentione they're nice enough to sponsor us.
You really like the DI system better but make more money with the piston. Right? :lol: :lol: :lol: :lol: :lol:Addax Tactical said:
It's fun needling each other. If this was ARFCOM, this thread would have been locked after three posts for getting out of hand and violating TOS.coldair said:i think he likes pistons systems better
The AR I have is so far DI. I tried to talk several companies into sending me a PWS piston system to install myself (as I love to tinker), but so far have not been able to shake anyone from procedure .
From what I understand and so far have experienced, DI versus piston is a moot point on most fronts. The only really viable arguements, in my view, is cleaning time (a point where pistons shine) and keeping heat out of the reciever (where you have lots of small parts that heat cycles will degrade, but switching to a piston moves the heat cycle issue to a different part of the rifle). In the end I think it's up to personal preference as each has its advantages and liabilities. On that note, it's probably best for you to sit down and look over the advantages and drawbacks to each system and decide what is better for your application.
.From what I understand and so far have experienced, DI versus piston is a moot point on most fronts. The only really viable arguements, in my view, is cleaning time (a point where pistons shine) and keeping heat out of the reciever (where you have lots of small parts that heat cycles will degrade, but switching to a piston moves the heat cycle issue to a different part of the rifle). In the end I think it's up to personal preference as each has its advantages and liabilities. On that note, it's probably best for you to sit down and look over the advantages and drawbacks to each system and decide what is better for your application.
I run a piston currently and it has done everything I've asked of it. Plus when I get home I don't have to spend the rest of the evening cleaning. In fact I usually only clean after every 3 trips or so and it only takes me about 15 minutes. This fact alone was worth the minimal extra charge for the piston.
I have two 6.8 uppers with Adams Arms Pistons. Both work flawlessly.
Both my uppers shoot 1" to 1.5" groups all day long. Thats not surprising,
what is surprising is that they are both MODEL1SALES 1-9.5" twist barrels.
I love the pistons. all I have to do is take a rag & wipe a little residue off the boltface,
ant pull the piston out the front, take a qtip & wipe the piston bore, and clean the barrel
like normal & I'm done. Took less than 10 min to clean each of my 6.8's last night, and I
take my time.
I cant say enough about how pleased I am with them. I even put an ARES on my M4 clone, but that will probably become a Adams Piston once I get over my " Its gotta look stock" fettish.
Yeah Yeah I know, I'd have something better if someone would sell me an 1-11" twist
barrel. I have two on order from GTS ( 1-10" ) & two on order from RRA ( 1-10" ).
I'll try to get a couple Extreme barrels once things settle down & they arent pressed to
meet the demand for their uppers. I'd place an order for two barrels today, but I figure I'd be
cheating two of you guys out of an upper, I can wait. Even if AR#5 is waiting on a barrel & rail
to be complete.
Ty Hoeffer
Charlottesville, VA
Both my uppers shoot 1" to 1.5" groups all day long. Thats not surprising,
what is surprising is that they are both MODEL1SALES 1-9.5" twist barrels.
I love the pistons. all I have to do is take a rag & wipe a little residue off the boltface,
ant pull the piston out the front, take a qtip & wipe the piston bore, and clean the barrel
like normal & I'm done. Took less than 10 min to clean each of my 6.8's last night, and I
take my time.
I cant say enough about how pleased I am with them. I even put an ARES on my M4 clone, but that will probably become a Adams Piston once I get over my " Its gotta look stock" fettish.
Yeah Yeah I know, I'd have something better if someone would sell me an 1-11" twist
barrel. I have two on order from GTS ( 1-10" ) & two on order from RRA ( 1-10" ).
I'll try to get a couple Extreme barrels once things settle down & they arent pressed to
meet the demand for their uppers. I'd place an order for two barrels today, but I figure I'd be
cheating two of you guys out of an upper, I can wait. Even if AR#5 is waiting on a barrel & rail
to be complete.
Ty Hoeffer
Charlottesville, VA
Both systems are good. I prefer the PWS but the Adams is a nice system. Unless Adams has a 6.8 dedicated system or made changes you may have to open up the gas port to get proper function. Adams is a relatively new company that kind of just popped up. Everyone has to have a start though so that is not necessarily a concern. As far as i know Adams only product is the piston system. Adams has come out with a nice one piece BC. Their system is user installed. I have heard many good things perf wise from people with Adams systems. The PWS is installed by a dealer. The PWS is a gentler system. The PWS has a adj gas block for suppressed/unsupressed shooting. PWS has been around a long time has multiple products and shows great inovation with new products.
PWS allows and will do pinning the gas block where Adams will void your warranty if you have it pinned. They say it will not move if properly installed. If its pinned there is no question about it.
As you can see in many ways it comes down to personal pref. For me personally I would go with the PWS but that is me. I am not saying the Adams is a bad choice.
PWS allows and will do pinning the gas block where Adams will void your warranty if you have it pinned. They say it will not move if properly installed. If its pinned there is no question about it.
As you can see in many ways it comes down to personal pref. For me personally I would go with the PWS but that is me. I am not saying the Adams is a bad choice.
how about both... I may keep my WOA upper DI since TimW fire lapped it with tubbs and cleaning is really not a big deal. I may have the Xtreme upper morphed into a piston upper by the guys at ADDAXX...
I also caught wind of the new delayed impingement gas stystem that PARA USA is offereing
I may keep my WOA upper DI since TimW fire lapped it with tubbs and cleaning is really not a big deal. I may have the Xtreme upper morphed into a piston upper by the guys at ADDAXX... I also caught wind of the new delayed impingement gas stystem that PARA USA is offereing
When I was working for Uncle Sam I had three long guns I became familiar with - a M16A2, a FN-FAL, and an AK. I didn't like 2 things about the M16A2 -- the caliber (too small) and the DI system. Now I have a rifle a bought - 6.8mm LWRCI piston -- and am happy
Honestly for 99% of those purchasing piston ARs the only real benefit being used is less cleaning. I very much doubt all but a very very few are running the round counts to matter and most do not use short enough SBRs to matter. For some a $1000 and even more surcharge for easier cleaning seems like a big premium for less cleaning. Not saying the guns are not everything people say just that most of the benefits are lost on the majority of purchasers. Some do need it but its very very small. Big dif between need and desire. Just something to think about while you are paying off that 3x credit card balance for the privilege. Some of the retros do make it much more appealing as a few hundred to not have to clean and some other benefits is more in line for what the everyday joe is going to use them for. Also these piston systems are still having the kinks worked out and developing even to this day and will be for the foreseeable future IMO. If you think these guns are heads and toes above the reliability of DI guns even using some of the more popular gas piston systems with hard use it seems they have quite a few of the same issues DI system guns have and have read about failure rate just as high. Not saying this is the norm or all units but it is credible. The systems are still evolving and there is no doubt in my mind that pistons are the future. There is also no doubt that as you beef up the system going to piston other parts of the ARs weaknesses come to the surface or new ones are created. As can be seen with the SCAR this will end with a totally new platform once all are addressed. But there is no doubt the piston is a very solid setup for sure, when properly built.
Thought I would throw out a different perspective to think about. BTW I do like piston uppers and will end up owning one but I also and under no delusion that it is over kill for most of what I am doing but they are so very nice it is hard to not get one if you can afford it. :mrgreen:
Thought I would throw out a different perspective to think about. BTW I do like piston uppers and will end up owning one but I also and under no delusion that it is over kill for most of what I am doing but they are so very nice it is hard to not get one if you can afford it. :mrgreen:
I just remembered another reason the piston appeals to me (though I have no intention of submersing my gun, nor shooting it if it happens, it's wet here and I can't argue with hydrodynamics).mavericks said:
ETA: Hydrolic properties in action:
Good post Tim... I can always count on you to slap some sense into me. I have owned 2 piston operated types FAL/SKS and they were not without thier own problems..in fact my FAL was pretty finnicky in its behavior which caused me to sell it for the 6.8 ar15...
I will have a piston upper eventually but I am going to lurk in the shadows in the meantime trying everything I can to make my DI run like a top... thats tubbs ff what a huge step in that direction, maybe next I can try a jp adj gas block and a larger gas tube... thanks again TIM , my DI barely needs cleaning if any....
I will have a piston upper eventually but I am going to lurk in the shadows in the meantime trying everything I can to make my DI run like a top... thats tubbs ff what a huge step in that direction, maybe next I can try a jp adj gas block and a larger gas tube... thanks again TIM , my DI barely needs cleaning if any....
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