Does Shrot Stroke Add More Gas Airsoft

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Just a question I've had:
Whenever you see the latest and greatest in military or tacticool rifles, they are invariably driven by a curt-stroke piston. The people that design these guns are no dummies, and they seem to accept decided near-unanimously that short stroke is the best choice for an assault rifle action. And I don't know why that is.

Long-stroke pistons, I can meet the point. Yous get a uncomplicated, jumpsuit action, moving with a lot of momentum behind it. Having all that weight reciprocate is a trouble for keeping the gun steady, only that action won't want to terminate.

DI systems, the Stoner system, any you lot want to call it, seems to make the almost sense from an applied science perspective. You "cut out the middleman" by just having the propellant gas drive the commodities direct: no piston, less weight, less moving parts. Having the gun spit its fouling all over the BCG is apparently a business, simply the current generation of ARs seem to run too as anything else. Either information technology's an overblown problem, or the AR has simply been refined and so much that information technology'due south pretty much been handled. And I've heard that the French MAS-49s were pretty hardy also.

So I don't know where that leaves you with short stroke. I honestly don't know the advantages and disadvantages it has, or why it's considered "the best choice" by the people actually out to win contracts, while DI and long-stroke are exclusively relegated to ARs and AK knockoffs. Anyone know why?
Just my two... Beers. Brusk stroke Vs. Long stroke - bolt carrier on the commencement is lighter, so you become less recoil, therefore you get fast recovery and in full motorcar you go better, tighter grouping on target. E'er try to burn down AK47 in total-auto? Trust me, it's difficult to keep on target even on relatively curt distances - the gun just bounces too much. You cannot experience that if shooting simply in semi-auto mode. Equally to the lighter commodities carrier volition be non so reliable compared to the heavy long stroke carrier - this is simply non true. You lot have more than than plenty weight for the gun to cycle reliably nether any status, and that'southward a battle proven fact, not just a theory.
Short stroke Vs. direct gas impingement - you simply become manner less carbon fouling into the bolt itself and to the bolt locking surfaces. Yea, in a perfect earth, with the right ammo this problem does not be, only with less than optimal ammunition (read dirty) ane can feel the advantage of short stroke system - it just keeps your bolt cleaner therefore the gun shoots for a longer period without misfires.
- Contributing Member
MidRoad Contributing Member
Different strokes for dissimilar folks
DI doesn't spit fouling on the BCG any more than brusque stroke. In point of fact the HK91 fouls the bolt merely as badly - information technology has NO gas action at all. Why? Because of timing - when the bolt unlocks on any self loading action the cartridge is freed upward to move to the rear, creating a much larger opening for gas to escape. The brass gets dirty on all cocky loading deportment, which is the proof. Gas escaping past the contumely is what dirties the bolt, non a gas tube located above information technology, partially shrouded by the key in the early portions, and fed past a pocket-size .061 port in the butt. The sleeping room is huge in comparing and dumps the residue into the activity - non the gas tube.
Pics posted of AK's online show them getting crusty and fouled after a few hundred rounds, too. The myth of DI being a dirty action by it's direction of gas is a 1960'south myth perpetuated by those who didn't understand firearms design. Information technology was a transition period for the American public still infatuated with manual action arms which released the cartridge example after the butt was completely exhausted, ejecting clean contumely. Self loading deportment are timed to extract while at that place is yet gas pressure in the barrel and they all get muddied, even the 10/22.

The Stoner blueprint as well has a gas cylinder inside the BCG sealed with piston rings on the bolt. In one respect it's curt activeness - the gas pressure level builds forcing the commodities against the breech while simultaneously moving the commodities carrier to the rear. Once the commodities lugs are unlocked further gas pressure of the cartridge against the bolt face adds to the rearward momentum of the BCG. The M16 can extract without the extractor - when timed properly. Gas pressure level in the barrel blows the cartridge case out. It's when the timing is off that we go extraction issues similar ripping the extractor off the rim. That's caused by besides early timing while the case is nevertheless expanded in the chamber. This is where correct selection of the gas port is important - you can do as you like, but picking the wrong one changes the timing and creates issues like FTE, high bolt speeds, bolt override, bolt bounce, etc.

Timing is more important than anything in a self loading activity and considering it's dynamic it's hard to see and measure. It's much like choosing a camshaft for an engine and I deal daily with cocky professed experts who can't begin to explain how it'south measured or what changes will do to valve timing and the results. It's much the aforementioned with velocity from short barreled AR's, some keep repeating that there is huge velocity loss when a butt is cut down to ten". The loss is a lot less than it seems and why the military machine still uses the CAR-fifteen after 45 years. They merely phone call it something else now.

Some volition differ only DI is brusk piston, and all self loaders spit residue on the commodities. Those of us who ain(ed) HK 91'south know that and don't repeat fake news.

edit: for those who insist a piston has to motility delight research aircraft radial engines that bolted the cranshaft to the frame and mounted the propeller to the cylinders. The "engine block" rotated and the piston was static. There is no engineering science Law that states which moves and which doesn't.
About the rotary aircraft engine:
The crankshaft IS stationary, merely the pistons do rotate with the jugs (obviously) and move every bit they travel around the crankshaft. I know...it'south difficult to describe something in a few words and you know what you hateful...just wanted others to be able to run across it then they can empathise.
- Contributing Member
CraigC Sixgun Nut
Didn't we just do this?
Isn't this thread about short stroke armed services rifles, not virtually aircraft engines?
Either way, they both go ....bang.
Before nosotros can have any meaningful discussion virtually the dissimilar action types, nosotros have to understand the basics, beginning with the fact that the AR direct gas (Colt's words) arrangement uses a piston. (It would too help to understand that the AR does not use a direct impingement system, but pointing out that fact seems offends those who have trivial to no understanding of technical details and I won't go into it in this thread.)Reciprocating mass does non decrease or increase recoil free energy. It only changes how the recoil feels to the shooter. Part of the recoil energy is stored in the reciprocating mass and isn't dissipated until that mas has finished moving. Whether or not a system has greater or lesser mass has lilliputian to do with the fact it's a long stroke or brusque stroke system. Information technology simply has to do with how the system is designedIf this were true, why does an AR foul more when a silencer is added? With an adjustable gas cake tuned to minimize gas menstruation to just what's needed to operate the burglarize, fouling in the action is much heavier. The only way that could happen is if the flow of gas through the chamber end of the butt is increased later extraction. Increased fouling of the action happens with ALL types of self loading actions The 10/22 uses a unproblematic blow back pattern. Extraction begins nearly immediately and earlier bore pressures driblet to safety levels. That's i reason uncomplicated blow dorsum designs are not used with high pressure calibersPressure in the expansion chamber is lower than that of the bore. The lower pressure in the expansion chamber cannot push button the bolt forrard against the higher pressure in the boreA rotary engine spins the entire engine, including the pistons. The pistons stay with their corresponding cylinders and the pistons do the reciprocating, not the cylinders
Have you shot an AK 47 (AKM, AK 74) in full-auto? Take you compared a similar short stroke system, firing in total auto? Because I accept done it. The unproblematic act of moving a much heavier bolt carrier is plenty for you to "feel" the recoil much more and see where you are (missing) on the target. And, by the way, energy means nothing here (and I do mean zilch) - what we are looking for is force.
Sure, until you try both for an extensive period of time with the exact same ammo. And then you wonder - should i believe my eyes (when the DI starts to choke), or the Internet? But shoot an M4 and FN SCAR for 2000 rounds, adjacent with some muddied ammo and compare them both.
Guys, I know that this is an "AR in a higher place all" forum and I'thousand not proverb that DI systems are inferior. All I'chiliad proverb is this: with "dirty" ammo the short stroke arrangement has an edge above DI, and faster target conquering then a long stroke arrangement. This is something I have witnessed and experienced. I don't care about "spherical cow in a vacuum" type of state of affairs - I did compare them in live, total-motorcar, fire.

P.S. Sips his cup of tea, puffs on his piping, filled with blood-red virginia, and waits stoically for the AR fan-crowd to roam this thread...
Heh, yes. Reminds me of the time I sent up an OR report that was FAR below xc%. I (and everyone else) expected screaming telephone calls to happen (and they did, eventually).
First time I shot an HK (afterward thousands of rounds through M16s and M4s), and I stripped the HK to clean it, I idea "What the...? Where is all the crud???

I hope your tea and pipe are enjoyable, on this fine Sabbatum afternoon.
The only arm I've fired total machine is the AR. Simply that does not change the laws of physics. Greater reciprocating mass does non change how much recoil is generated. One 10 pound rifle pushing a 150 grain bullet with 62 grains of powder to 2800 fps generates just as much recoil as some other, whether that rifle is a bolt action, AR or AK. All the same, the recoil will feel different considering of reciprocating mass, recoil vectors, butt pads types, etc.
Greater reciprocating mass will bounce a burglarize around more than lesser reciprocating mass. For example, a rifle that weighs 10 lbs and has a reciprocating mass of two pounds. 20% of the rifle is reciprocating mass. Compare that to a 10 pound rifle with a four pound reciprocating mass, or 40%. Part of the recoil is stored in the reciprocating mass. The greater the mass, the greater the recoil information technology stores. The greater the percentage of of the reciprocating mass the greater the percent of the recoil it stores then releases.

The greater reciprocating mass of the AK does NOT increase recoil. It only stores and releases more than recoil. This combined with recoil forces not inline with the bore and buttstock and inferior ergonomics conspire to brand the AK less controllable nether recoil
As you can see, it has nothing to exercise with sipping tea or being function of the AR fan-crowd and everything to do with physics
Skilful point. Contumely coming out an HK91 is FILTHY. And then when it comes time to clean the bolt, information technology'south like "how can the contumely and bedchamber be so disgusting and the bolt be so clean?". Encarmine Germans.

bnolsen and cdb1 like this.
So, at the cease, nosotros have more force delivered to the shooter's shoulder? Because more force is pushing on that burglarize at the end of bolt carrier's travel, correct? The force generated by the same bullet, but in different systems is the same, simply the perceived recoil is different. This is what I'm talking almost. This is what matters after all - recoil, every bit perceived past the shooter, not what the bolt bears. The residue is semantics. Non physics, semantics - because the terminate of the recoil cycle matters to physics as much every bit the starting time of information technology. And I DID savour my tea, give thanks you...
Yeah. Felt recoil, which you call perceived recoil, differs with each firearm. Simply it does not change how much recoil is generated. It just changes how the shooter feels or perceives the recoil.
There is no extra force pushing back on the shooter's shoulder. There is just force that's delayed until the mass hits the end of information technology'south travel. If that mass is heavy and there is a sudden cease, that transfer will quick and sharp, like striking a brick wall with a motorcar. Simply if the transfer is slowed, similar using the brakes before hit the wall, the transfer is softer. The force is the same.

Don't forget, for every reaction, there is an contrary and equal reaction. When the reciprocating mass is pushed back, the rifle is pushed forwards. When the reciprocating mass is pushed forwards, the burglarize is pushed back. A ten pound rifle with a two pounds of reciprocating mass (the unsprung weight) has a non-reciprocating mass of eight pounds. But, a 10 pound rifle with a four pounds of reciprocating mass (the unsprung weight) has a non-reciprocating mass of vi pounds. The burglarize with four pounds of reciprocating mass is going have more than reaction from the action of the reciprocating mass than the burglarize with the two pound reciprocating mass impacting control during recoil.

There is a difference between felt recoil and free recoil. Let's say two dissimilar rifles, both generating sixteen ft/lbs of free recoil. 1 has a soft, recoil pad half dozen inches long and two inches wide. The other has a steel barrel 6 inches long and 1/8 inch wide. The narrow butt won't transfer more recoil strength to your shoulder, just painfully concentrate it in a smaller area. Costless recoil is the aforementioned. Felt recoil, or perceived recoil- radically dissimilar

adcoch1 and cdb1 similar this.
Yes. Felt recoil, which y'all call perceived recoil, differs with each firearm. But it does not change how much recoil is generated. It just changes how the shooter feels or perceives the recoil.
There is no extra force pushing dorsum on the shooter's shoulder. There is only force that's delayed until the mass hits the end of it'due south travel. If that mass is heavy and there is a sudden stop, that transfer will quick and sharp, similar hitting a brick wall with a car. But if the transfer is slowed, like using the brakes before hit the wall, the transfer is softer. The force is the same.

Don't forget, for every reaction, there is an opposite and equal reaction. When the reciprocating mass is pushed back, the rifle is pushed forward. When the reciprocating mass is pushed forward, the rifle is pushed back. A ten pound rifle with a 2 pounds of reciprocating mass (the unsprung weight) has a non-reciprocating mass of 8 pounds. Only, a ten pound burglarize with a four pounds of reciprocating mass (the unsprung weight) has a non-reciprocating mass of six pounds. The rifle with four pounds of reciprocating mass is going have more reaction from the activity of the reciprocating mass than the burglarize with the two pound reciprocating mass impacting command during recoil.

Let's say ii different rifles, both generating sixteen ft/lbs of free recoil. Ane has a soft, recoil pad 6 inches long and two inches broad. The other has a steel butt 6 inches long and 1/eight inch wide. The narrow butt won't transfer more recoil force to your shoulder, just painfully concentrate information technology in a smaller area. Free recoil is the same. Felt recoil, or perceived recoil- radically unlike
Extraction timing, which determines the amount of blow-by as a case extracts, has nothing to exercise with gas system type. That'southward secondary follow-on aspect of the overall dynamics of the gun (equally is render spring force, carrier travel distance, and overall BCG mass). You can take long-stroke systems that have a long plenty dwell time, and yous'll get no blow past; the before designs final century worked this manner as a protection measure confronting case & overpressure failures. Blowback designs, like the filthy 10-22, are specially prone to fouling from accident by, since they extract much earlier than locking breeches.That's because the AK organization vents piston gas direct into --wait for information technology-- the expanse above the bolt carrier. The piston travels ~1/2", the gas chamber the uncorks and excess gas volume (which is a lot in an AK) flows around the piston inside the gas tube area and into the area beneath the dust cover. That's why excessive backpressure from cans or rechambering jobs in an AK tin can crusade the dust encompass to accident off. This is usually, but non universally, an issue with long-stroke systems, since the piston is generally housed in a continuous conduit to fully shroud it (and the piston is continuous with the carrier). Other designs, the RPD comes first to listen, accept either a gap between the tight-fitting gas chamber/gas cup and the entrance to the bolt carrier channel portion of the receiver, or very generous venting to the sides or front and below the bolt/chamber area (the BREN was kind of like this)I'm non sure why, but in that location's this whole myth out there about the AR gas system, where pressure at the finish of the gas system can be higher than at the gas port. The only way the bolt is getting driven against the breech is if the strength behind it is greater than the force in front of it. That means that gas pressure inside the bolt must be higher than in the chamber, but there's the lilliputian problem of the gas tube connecting the 2. The gas port & tube human activity as an orifice, dropping pressure as gas flows through them, which further ensures that chamber pressure level will always be college. While the flow tin can momentarily reverse as the bullet exits the muzzle and the chamber pressure speedily drops, this is both very late in the unlocking cycle and incredibly cursory (far faster than the inertia of metallic parts can react). The potential forces involved are likewise tiny since the sleeping accommodation/carrier both lose pressure simultaneously later on the bullet leaves, reducing the differential between the two that could potentially push the commodities forward. If at that place were a bank check valve in the gas key that prevented backflow into the bore, and then this 'after pressure' result against the bolt tail all throughout the unlocking cycle would be believable. All the same, it would make the 'self extracting' myth alleged of the DI organization impossible; the bore pressure must drib faster (almost instantly, which it does) than the commodities carrier afterwards fully unlocking (at which indicate it is vented at the gas key and internally IIRC) fifty-fifty though its pressure and gas volume are much smaller. Not happening.
The mundane reality of the organization is; gas knocks the carrier rearward correct as the bullet passes the gas port, the carrier begins rotating the bolt only before or later on the bullet leaves the butt (depending on timing), and if timed toward the early side (roughest on the bolt lugs and extractor) a modest puff of gas escapes around the case. No unlike than any other system as far equally those principal/secondary extraction dynamics. I would agree that the AR DI system more closely approximates brusk stroke performance, because it ane) delivers a brief strong impulse to the carrier early in the cycle, with a mechanical dwell before unlocking the bolt after the driving force is gone, and 2) does non add mass to the BCG assembly every bit function of delivering this impulse. In a way, information technology'south shorter than curt stroke, because no additional mass is added during the driving phase when a short stroke piston is active, meaning a given force will accelerate the BCG faster than if there was a piston/tappet (so y'all could become away with a smaller gas pressure contribution than with a short or specially long stroke organization)
You're right, it is exactly like an engine'south timing. Simply engines aren't timed based on gas dynamics betwixt two connected volumes of gas at different pressures, simply by solid mechanical interference of cams and lifters. The closest analog in automotive to what is being claimed in the AR gas system is intake/frazzle dorsum pressure due to acoustic effects in the tubes --and those furnishings are nowhere virtually significant enough to impact engine timing (equally opposed to pure optimization, which they obviously are). That, or designing an engine to depend on a caste of valve float to fourth dimension properly.Oddly, my FNAR cases come out clean, and after thou rounds, only the tappet piston expanse has powder fouling. The oil cleaned at the breech area is tinted grey, vs. black similar near the piston area. Fired rounds fume for several seconds later ejection then some soot escapes during extraction, merely it has zilch to exercise with a higher internal pressure. I'thou non certain what an HK roller gun has to practise with gas operated locking systems, but I do know a swain who goes by Holescreek who made a short stroke piston-operated CETME on modified roller-delay parts so he didn't take to make a fluted 243 chamber, and IIRC his brass came out clean, also.
TCB
The funny affair is, an autoloading firearm is constrained by more than pure momentum. To get reliable ejection from an AR or any other blueprint you need a certain minimum carrier speed, and total travel against a hammer/striker & render spring, that is itself strong enough to so reliably feed from the magazine & close the action. This puts up a "Limbo bar" on how wearisome y'all tin knock the commodities back. For a given minimum speed, a lighter carrier has less inertia, and will result in less felt recoil. The upper limit is of course how much yous can overdrive the carrier velocity before jacking up cases trying to extract them while pressurized, or breaking the gun when that carrier slams to the rear.
We also have the boosted contributor to recoil that I haven't seen brought upward which is backlog operating force. Gas systems all human activity as muzzle boosters. That is to say, they all straight some portion of the sleeping accommodation pressure back toward the shooter. In a 1919, it is applied correct at the muzzle via the booster associates to drive the barrel dorsum and operate the gun assertively for reliable function. In an AR15, it is applied to the inside of the bolt carrier to knock it dorsum away from the chamber. Information technology's of import to realize that ultimately, almost every bit of gas that is tapped from the diameter goes into increasing felt recoil for the shooter. Some guns, like the Galil or virtually short-stroke designs, minimize that volume of gas or apace vent it to the sides/forward before it can contribute all of its expansion free energy to recoil; they take low felt recoil in performance. Some guns, like the AK47 or M1 Garand, tap excessive quantities of gas from the sleeping accommodation to bulldoze the carrier harder than necessary (or for a longer elapsing) to ensure a healthy reloading bicycle, and all that backlog eventually slams into the receiver when the carrier reverses direction. At present, things like a longer carrier travel or slower operating speed tin can reduce the perceived recoil impulse, but the kinetic energy delivered to the shooter will always exist higher than for a more efficient organisation. The AR is definitely the most efficient, reflected in the light weight and tunability of its BCG components, short stroke slightly behind it, long stroke guns afterward that, then short recoil followed past long recoil (the weight from the moving barrels ensures they accept the highest operating mass:energy ratio). The uncomplicated realities of geometry dictate that the differences between them go more than stark as piston length increases (Krinkov/AR pistol vs. PSL/SCAR)
To exist fair, that trunnion is really, really, actually deep on the HKs. Plenty of volume for that gas to expand into and irksome down, then it doesn't blast into every nook & cranny of the gun. Judging past smudges (scientific, I know) not much gas volume fifty-fifty escapes the HK chamber at meridian pressure level anyway, the venting but happens well into extraction when the bolt is already or nearly unlocked (which should be obvious considering the lack of ruptured/torn/bulged cases in a properly made gun). FWIW, the STGW57 is the same style, with the within of that cavernous trunnion being the simply muddied part of the whole gun kit.
TCB
When you pull your charging handle dorsum, the burglarize flies forrad off your shoulder? A better way to describe what's happening is that the piston gas is pressing on both the gun and the piston, and equally so. Just again, all isn't equal in practice, since fifty-fifty though i gun's reciprocating mass may be double that of some other's, I'd bet it's operating speed isn't half as slow. I'd besides bet information technology information technology isn't equal in overall weight either, since and then much moving mass will undoubtedly put much greater strain on the receiver both coming and going, and crave reinforcement.
Design extremes tin be useful for demonstrating these kinds of interactions; information technology would be interesting to see how different recoil in an MP7 would be with the gas on vs. off. The round has such a tiny recoil energy compared to the mass of its operating components, it'd be funny if the cycle was more than noticeable than the 'kick' from the actual bullet.

And so you have the interesting conundrum that e'er comes from these discussions, of balanced actions, which involve components shifting reverse the carrier to counteract the jostling of operation. The most interesting of these (practically all Russian) designs was this one, which opposes carrier inertia with the other heaviest component in the gun; the barrel:

I'd retrieve with this organization, the only recoil delivered to the shooter would be from the bullet/pulverization gasses, and with a small-scale diameter bullet & cage restriction/silencer, not even that. This type of activeness has long-stroke or DI as a huge advantage vs. short stroke, since the masses of the 2 inertially-balanced halves stays the same throughout the cycle. It'd be cool to replace that long, heavy piston & carrier nose with ii opposing gas keys that come to the aforementioned stationary gas tube.

TCB
Yep. We sure did.
And I don't think nosotros came any closer to settling the dispute about whether the AR-15 "piston inside the BCG" actually constituted a short stroke piston or was merely a variation of Ljungman'due south direct impingement system.

The simply way to "settle" the dispute would exist to actually instrument upward an AR-fifteen then determine how much of the impulse for moving the commodities carrier (which cams the commodities to release) is generated by the gas bock resisting the flow of gas as it redirects information technology from the gas tube and into the "cylinder" of the BCG and how much of the impulse is generated by the ill-fitting piston rings slowing the menstruum of gas and thus pressurizing the BCG.
"felt recoil" is a function of mass and velocity, not inertia.
A simple orifice does non reduce pressure. It slows the menstruation. If the system were sealed, the gas would catamenia through the gas port until the pressure was equalized on both sides of the port. What happens when supersonic gas flows through a restriction is it slows to the speed of audio.The carrier does not brainstorm moving until the bullet has cleared the muzzle. The action of a gas powered rifle operates on the residual pressure level left in the organization after the bullet uncorks the muzzle. The pressure in the diameter does not drop instantly, it takes time, simply like letting the air out a balloon
HA! Seriously no, because there is an opposing forcefulness resisting the movement of the burglarize and then the charging handle can pull the carrier to the rear. Newtonian physics at workThat's what I said. As the reciprocating mass (unsprung mass) is pushed rearward, the greater non-reciprocating (sprung) mass is pushed frontward. But because the reciprocating mass is smaller, it gets pushed back more than the non-reciprocating mass gets pushed frontwards. That'due south what happens when a bullet is fired. Because it has less mass, it is accelerated forrard at a greater rate than the firearm is accelerated to the rear
Really, past the time the gas gets to the expansion chamber in the bolt carrier, the pressure level in the bedchamber is pretty shut to the pressure level in the carrier.
Brusque stroke pistons accept less mass off-center of the principal thrust line compared to long stroke pistons. Compare where the CG of an AK bolt carriers is to where the CG of an HK 417 or AR-18. This changes the dynamics of how the burglarize moves.

Long stroke pistons tin give increased piston thrust by delaying the venting of the cylinder, which why they are common in belt fed weapons which prefer a long continuous button to work the belt feed.

With automatic weapons, information technology is a question of momentum. You accept to impart enough momentum to the reciprocating mass in club for it to complete the wheel of operations. Since momentum is mass times velocity, for any stock-still momentum, the minimum for reliable operation, you can have a pocket-sized mass and a high velocity, a large mass and a low velocity, or something in between. The everyman possible velocity practical is the all-time option, every bit the lower the velocity the lower the impact forces and general stress on the parts.

From weight stand point, the short stoke piston blueprint is the worst option, as you have the weight of the piston/operating rod and cylinder not contributing to the recoiling mass, but are still accounted for in the overall weapon weight. Stoner's blueprint is the most efficient employ of weight as both the piston and the cylinder are office of the reciprocating mass.

There are drawbacks, as in that location is a considerable pressure level drop between the two ends of the gas tube, which make this organisation more than sensitive to port pressure. (Not insurmountable, merely it is more sensitive.) There is besides the fact that there is a large temperature drib along the gas tube length, meaning that any solid precipitates in the gun gas can clog the tube and also more than solid precipitates are deposited in the cylinder, whereas in a cylinder mounted closer to the gas port (as in nigh long and brusk stroke piston designs) will tend to exhaust this earlier they cool enough to precipitate out (depending on the piston particulars, of grade). Information technology also more than sensitive to leakage in the piston (the AR needs at to the lowest degree one piston ring, for a very tight piston seal every bit opposed the simpler labyrinth seal found on most pistons).

There are a lot of ways to skin this detail true cat, and which fashion you choose depends on the shape y'all want the hide to be when your done.