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Gas Systems - Piston or Impinged?


Frankh252

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Impingement for me. Lighter weight, fewer proprietary parts, and less expensive in general. I've got a P716 that uses a short stroke piston system, can't say it runs that much cleaner with all the brass shavings that get ground into the bolt and lugs, still gets a bit of carbon as well. My NiB BCG is just as quick when it comes to cleanup. I don't see any real advantage to the heat issue either, full auto it might come into play but the barrel gets just as hot in both systems I have.

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Why should we have to prefer one system over the other? Yeah why? I'll take either depending on the rifle, but I won't change over just because it is a change, if you want to do a change ,there are probably over 50,000,000 babies with Shittie  diapers that need changed so if you just like change go find a stinky bottomed baby and do a change. 

 

 

Edited by mrmackc
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Impingement for me. Lighter weight, fewer proprietary parts, and less expensive in general. I've got a P716 that uses a short stroke piston system, can't say it runs that much cleaner with all the brass shavings that get ground into the bolt and lugs, still gets a bit of carbon as well. My NiB BCG is just as quick when it comes to cleanup. I don't see any real advantage to the heat issue either, full auto it might come into play but the barrel gets just as hot in both systems I have.

Thanks, Jtallen. My 308 Oracle is impinged & works fine. Thinking about buying a AR15 piston-type but just fishing for input.

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Why should we have to prefer one system over the other? Yeah why? I'll take either depending on the rifle, but I won't change over just because it is a change, if you want to do a change ,there are probably over 50,000,000 babies with Shittie  diapers that need changed so if you just like change go find a stinky bottomed baby and do a change. 

 

 

I'm not aware of anyone saying you have to prefer one over the other, or change one to the other. If you like changing diapers, knock yourself out.

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I'm not aware of anyone saying you have to prefer one over the other, or change one to the other. If you like changing diapers, knock yourself out.

hey sir I am not someone that likes changing just for the sake of change. Wasn't me that started this topic about,well you were the one asking about preferences, don't preferences have something to do about which system we prefer?

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hey sir I am not someone that likes changing just for the sake of change. Wasn't me that started this topic about,well you were the one asking about preferences, don't preferences have something to do about which system we prefer?

I have a few military buddies who think the reliability of the piston system is better, gives a reduction of carbon buildup on the BCG and requires less carbon scraping and cleaning. Con's would be more moving parts to maintain or repair/replace. Now, I'm not thinking of changing the system on my 308, nor do I prefer either over the other, but I would consider getting a piston-type 5.56 if it provides benefits that warrant it.

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The way I look at the whole thing it's one of those "great dibates" along with "glocks or any other pistol" and "ar or ak" it just always ends in a pissing match and no one is right there are pros and cons to each. 

My next gun will be piston, why? Cuz I don't own one, and I'd like to.....

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The way I look at the whole thing it's one of those "great dibates" along with "glocks or any other pistol" and "ar or ak" it just always ends in a pissing match and no one is right there are pros and cons to each. 

My next gun will be piston, why? Cuz I don't own one, and I'd like to.....

Yes, sir. Never won a thing in a pissing match anyway

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Impingement for me. Lighter weight, fewer proprietary parts, and less expensive in general. I've got a P716 that uses a short stroke piston system, can't say it runs that much cleaner with all the brass shavings that get ground into the bolt and lugs, still gets a bit of carbon as well. My NiB BCG is just as quick when it comes to cleanup. I don't see any real advantage to the heat issue either, full auto it might come into play but the barrel gets just as hot in both systems I have.

Thanks for the input, jtallen. One opinion I heard (not that I have any knowledge it) is that impinged is a little better for tactical/combat use while pistons are better suited for match shooting but I have no doubt a great shooter could skin flies with either type. I think both are good systems and would use either one that's available.

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I thought the extra moving parts of a piston system would make them less accurate but then I will never be a good enough shot to judge the difference myself.

Lucky for me, because I'm not that good anyway, I don't need to be gnat-shooting accurate. We just have a bad feral hog problem around here.

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Doesn't that heavy piston system clamped to the barrel defeat the purpose of freefloating?

Isn't the purpose for FF'ing different for various uses? I need picatinny attachments out on the far end of the barrel. Others want no interference with the harmonics of the barrel (where a bolt-action is better than an AR even when impinged). I've seen some sweet pics of piston-guns sporting some mighty fine rail hardware.

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Free float main purpose is to keep any pressure off barrel for the sake of accuracy. Side bonus is being able to run a handguard longer than your gas system. You can hang stuff off of non floated handguards just as well as floated. There was a article a while back where a guy showed some pretty big POI changes with non floated handguards and a bipod. Obviously wouldn't be as bad with a piston since the weight of the gun isn't resting on the end of the barrel, but I'd think it would have more affect then a gas block. Only reason I brought it up is because it seems it wouldn't be as good from a competition standpoint. I was just thinking out loud though. I have no experience, and no desire to own or build a piston AR. the system wasn't designed to work that way and its just different for the sake of being different for as I'm concerned. I have zero of the problems a piston is suppose to fix. 

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Only kind I ever had was impinged & they work great with the proper length tube. And I don't know anything about harmonics. Seems like any kind of attachment point on a barrel, whether pistons, gas-blocks, sights, bipods, etc, could disturb the harmonics of the barrel? What do bad harmonics do anyway, make the barrel hum & vibrate like a tuning fork? lol

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  Harmonics make the barrel have a long wave action. Sometimes in horizontal or vertical action and different points. I believe it is caused by the bullet torque action in the rifleling. JMHO

Back when we started glass bedding bolt actions we did a small barrel pressing point out near the end of the forearm believing it was good to disrupt the barrel harmonics but when experimenting with how much pressure contributed to accuracy it was discovered that free floating worked best when the receiver was very rigid. I glass beded a 03A3 several Mauser action 2506 rifles and the freefloated ones were more accurate. I used sandpaper to freefloat until a playing card would easily slide between the forearm and the barrel. Accuracy was improved on both a cold barrel and a hot barrel.

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If a DI was subjected to heavy military use in dirty and extreme conditions, firing a high volume hodge-podge mix of whatever ammo was available even (gasp) steel-cased, could the carbon buildup become so severe that it would require carbon removal in order to prevent a failure? If so, is that also true for a piston?

I know we're not going to melt gas tubes and bend barrels with a semi-auto but like an energized bunny a SA can just keep on going & going as long as ammo & finger muscle remain.

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The DI system is basically a piston system the "piston" is just in another location. it would take a good bit of carbon to jam either system. In my experience with high volume shooting in the M-16 the carbon buildup would end up breaking up and being blown through the system, it wasn't hard enough to cause any failure. Shooting blanks in training was the worst as far as carbon buildup but still never saw an issue even when no lube was used.

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There was a thread in here where someone was arguing that his LWRC M6A2 was God's gift to the AR platform. Someone else posted an article written by a guy who runs one of those Vegas gun ranges with all the cool rental toys. I'm pretty sure that place is harder on guns than even military service, and his experience was the piston guns can't hang with that type of abuse. I don't feel like digging it up but maybe someone else can post it.

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