GBB Pistol barrel length testing
 

I did some experimenting with barrel lengths and BB weights since I had them lying around. This is NOT a scientific test and there are MANY uncontrolled variables so please take this with a grain of salt and only in a broad sense. If anything, it makes for some amusing lunchtime reading for you.

I have two WE pistols which came with longer barrels (190mm, 215mm) to allow them for import. One is clearly brass and the other is a smooth chrome finish but I suspect it's just a rough steel inner. I do not know the inner diameter nor anything else other than the length. This is an uncontrolled variable.

The test platform is the WE G27 STOCK pistol. I forgot what the stock inner barrel is but it's quite short... probably around 75mm?

I've posted the targets shot at 20ft range in a crouched stabilized position. This is an uncontrolled variable. The numbers correspond to the BB weight (brand Elite Force), barrel length, and median FPS. The targets are not sized to any standard so only compare them against each other. The longer barrels are NOT stabilized inside the silencer tube. This is an uncontrolled variable.

THE SETUP:

http://images.tapatalk-cdn.com/15/08...1e24515d7a.jpg

STOCK BARREL:

http://images.tapatalk-cdn.com/15/08...e2ec31a6f5.jpghttp://images.tapatalk-cdn.com/15/08...a1164ef7e4.jpg

MEDIUM BARREL:

http://images.tapatalk-cdn.com/15/08...5ddb7cb2ef.jpghttp://images.tapatalk-cdn.com/15/08...e76511f39a.jpg

LONG BARREL:

http://images.tapatalk-cdn.com/15/08...fc809b311f.jpghttp://images.tapatalk-cdn.com/15/08...1c72dea1e1.jpg


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After my testing, I decided to let my Marui G26 with a short 6.02 barrel have a go for my own comparison purposes...

http://images.tapatalk-cdn.com/15/08...538952b5f5.jpghttp://images.tapatalk-cdn.com/15/08...7f98e7406c.jpg

Draw whatever conclusions you will from this. I spent the time to do this for myself so I thought I'd share. Again, this is a very unscientific test.

Barrel length makes no difference to accuracy. Only quality matters.
Bb weight and hopup are the two biggest factors in accuracy, followed by muzzle energy and barrel quality.

Thanks, I'm learning... and also that a decent hop up rubber is the most effective investment one can make.

Having said that, can you speculate on why the grouping from the short stock barrel to the mid barrel grouping is so different? Again, this is at 20-25ft only. I mean it could be that the stock shortly barrel is just terribly finished?

Without knowing any better, I'm just going to quote the "What a longer barrel WILL do for an AEG is give you a tighter grouping at longer ranges" from the "Why do I need to upgrade (or not) - with explanations!" sticky. Granted, it notes AEG but in this instance/range I guess it could apply to GBB?

The difference is more likely due to the changed weight of the pistol affecting your handling of it.
Honestly at 25ft, groupings really don't mean anything at all, and if you're not using a gun vise, ESPECIALLY on a pistol, then the groupings are highly subject to your own personal skill.

AEG's, GBB's, GBBR's, HPA, spring, etc, they all have the exact same shot potential.
What matters to the BB is the pressure of the substance being used to center it in the barrel, and the consistency of that.
A .30g BB being shot at 1.6j from any of the above type of gun has the exact same potential for shot performance.
The BB doesn't care WHAT medium is being used to propel it; air, propane, CO2, nitrogen, compressed farts, they all do the same thing.

Barrel length doesn't matter because a) the hopup is applied at the very start of the BB's travel, and b) the rate at which the BB becomes centered in the barrel is proportional to the initial gas pressure generated.
What that means, is a gas pistol with a 5" barrel shooting 1j is going to perform the same as say an MP5K with a 5" barrel shooting 1j on a ported cylinder.

Okay so now range and accuracy have nothing to do with barrel length, since once the BB is centered in the barrel, it is centered, and no extra amount of barrel will ever make it any MORE centered than it already is. Depending on your initial pressure it could be centered in the first half inch, or the first 4 inches.

Barrel bore has nothing to do with range or accuracy either. Since the BB never actually touches the barrel wall, it just rides a cushion of compressed air down the barrel. So the size of the bore doesn't matter as long as the BB is still riding the air cushion.

When we talk about accuracy at range.....
Your gun is dead accurate to 160ft, like we're talking groupings the size of a quarter, but it has trouble hitting a volkswagon beetle at 240ft. Now think about this really thoroughly; do you think the accuracy loss between 160 and 240ft has to do with your barrel? Or do you think it has something to do with the BB and the hopup?
Factually, your barrel only makes your gun accurate within the first 50ft or so. Beyond that, hopup and BB weight take over.
Because the BB quite literally flies itself to target (the magnus effect turns it into a little wing), it's weight and the stability of it's backspin are what make up the bulk of your accuracy at long range. The rest of it is how rigid your barrel group is, fps consistency, air bubbles in the BB, various outside factors. But the majority of the performance is dictated by BB weight and backspin.

Simply put:
-If your BBs fly straight, then flay out wildly in random directions, you need to use heavier ammo
-If your BBs fly straight, drop gently, but the flight path varies slightly left to right, you need better BBs or more likely a better hop rubber. Sometimes this can be caused by the slack in all your parts (like the inner barrel being loose in the outer barrel, etc)
-If you get better range with a .25 than you do with a .28, you need a better hop rubber that puts more backspin on the BB
-as a rule of thumb, to select BB weight, keep increasing the weight of the BB until you start losing range. So if you run .30s, then gain range on .32s, then lose range on .36s, then you should use .32s, or upgrade your hopup to use .36s

That's the thing... the groupings vary enough to almost rule out the individual skill bit. I didn't stabilize the silencer any more than I did without it so the vast increase in accuracy is an interesting find in my uncontrolled experiment. I do hear the lack of controls makes some results suspect. I'm leaning towards the stock barrel is rubbish... though the "free" extended barrels can't be that much better so the only variable left is length. Again, in a very broad sweep of considerations.



So would the WE G26 barrel be so short that adding any length of barrel allows for the air to stabilize the BB further... or something like that? The alternative theory is that the extra 80-100mm is the difference between a tighter and loose grouping. That is, if I step back 200mm would I see the same spread using a longer barrel? I need to try. Of course, the spectacular groupings using the TM G27 and short 6.02 is astonishing for me when compared.



I remember in my travels the debates (or fact?) where a moderate quality tightbore will allow for greater accuracy at short distances, sacrificing long range. Just a general comment.




This, I already subscribe to and understand :smile:



Thanks for the summary. This is how I came to my other thread about velocity... I am all for shooting 0.28 if it increases potential accuracy. The TM rubber should be ok to start with 0.28 but only testing will tell. However, at some point the other inefficiencies some into play and you need better valves, seals, longer barrel (?) to ensure the BB is propelled at a reasonable (?) speed.

Take a read through the "how airsoft guns really work - the physics" thread in the noob section, lots of good in depth explanations in there

a higher quality barrel will increase groupings at all ranges, assuming your stock barrel was of poor quality to start.
There no "it does X, but sacrifices X", it simply improves accuracy across the board.

Range is absolutely entirely 100% determined by BB weight, hopup, and muzzle energy. weight and hopup having the greatest effect.
For example; a gun shooting 1.4j and one shooting 2j, both shooting .30s with the same hop rubber, the 2j gun will get maybe an extra 10-15ft of range.
But if the 2j gun is shooting .36s, it could gain 30-50ft

I'll say it again:
Range has absolutely nothing to do with your barrel, and everything to do with your BB weight, hopup, and muzzle energy.


Where this misconception takes root is when idiots upgrade their barrel and hop rubber at the same time. So they go from a 300mm stock barrel with a crappy stock CA hop rubber, to an Rhopped 509mm prometheus 6.03, and then they attribute all their gains in accuracy and range to the barrel, particularly the length of the barrel, instead of the hop rubber which is what's actually improving their range and accuracy.

Thanks, I'll read that thread. I have no misconceptions about range. The first few articles I read already ingrained that. I'll be doing some more unscientific testing for my benefit at 50ft. I drew an early conclusion of "assuming your stock barrel was of poor quality to start" as it's the only plausible explanation for my limited knowledge.

I missed a word in my reply. What I meant to say was... "I remember in my travels the debates (or fact?) where a moderate quality tightbore will allow for greater accuracy at short distances, sacrificing long range accuracy.

You should try installing the barrel and hop-up rubber from your Marui G26 in your WE G27 and see if there is still a difference in accuracy. My guess is that you are using the stock WE hop-up rubber, which is absolute crap. Also, hop-up rubbers don't like oil, especially the stock WE rubbers, you might want to clean it thoroughly with dish soap and try again.

On the KJW G27 (and G23) the outer barrel has a lot of play in the slide, which seriously affects accuracy. If the WE has the same kind of play, it might explain part of the poorer accuracy versus the Marui G26.

Thanks mate it's not so much a comparo of the TM vs WE, but you definitely have a point and I agree from stock, the WE is leagues behind the TM for the rubber. I'm not going to swap the rubber it's beyond my unscientific test scope. What intrigued me was the barrel to barrel test of just the WE itself. I'm very happy with the way the TM G26 is running, only wish it can run a little faster (BB that is) towards the target. Though getting that result is an extreme case of diminishing returns from upgraded valves, etc.

In the meantime, I'm "running" the WE G27 with the longest barrel and silencer. It's just a "fun gun" which I wasn't even supposed to get, it was an accident hence a second class citizen to the TM G27.

What I will do is thoroughly clean the WE rubber and see how that affects things in a broad sense. Thanks for the tip.

aftermarket hop rubbers are generally much better
but pistols looooooove heavy ammo as well

So bear with me for a moment. The TM rubber is pretty good out of the box. I would go a heavier weight (past 0.25) in this case, why?

Let's say I do go 0.28, the FPS would be lower and the hop up may struggle. So I upgrade the hop up but now I need more gas to propel the sucker. So I need to upgrade the mag valve, knocker, perhaps hammer, etc. What I'm suggesting above would be a very incremental return on effort, is that right? Assuming engagement distance of no more than 60ft.

the stock rubber can lift .32s no problem.

Sounds to me like you want the best of both worlds.
Either that or you don't really know what you want your gun to do.

If you're so desperate on getting a higher FPS, why don't you just invest in a CO2 mag or something?

If you want your distance to shoot past it's limits, use your rifle or something similar to your pistol (like an SMG) that's designed to carry heavier bb's.

This is not true. The other variable is you. The only real way to absolutely attain identical results is to use a gun grip like TC suggested. Otherwise, regardless of how "solid" you think your technique is, evidence shows that at some point that variable has changed. And the factual evidence of this is your results...

A high output blowoff valve is not as beneficial as you think it would be. They are only as good as the temperature the mag is operating in. Thus, if your magazine drops in temperature (which it will), that blowoff valve becomes basically moot. The kicker is that because of it's perpetuancy to let more propellant out of the mag, it will speed up the cooling of your magazine. What will happen is that you will get the FPS output that you desire for the first three of four shots then it will eventually normalize and drop your FPS values to norms (or a bit higher).

A pistol is a viable primary but i think it's a poor choice. Unless the game your participating requires you to use it ( like say IPSC type settings ), then there really is no need to bust it out.

You'll come to realize this fact the more you stick with airsoft and more the experience you gain....

I need a BB sampler pack...

I do understand the limitations of the choice I've made indeed. It's a similar argument I had moving from a BMW 545i to now a 3cyl Twin Turbo Mini Cooper. I will play within the maximum potential of the platform and love the challenge. It's torque not HP that wins CQB. No wait... :)

Anyhow that valve tidbit is extremely helpful to put things in context. I will push my KWA G17 to a sane limit and run 50 round mags. Since I don't do outdoors, it's a viable option. For outdoors play I have a few to choose from...

http://images.tapatalk-cdn.com/15/08...b2be184ae9.jpg

The bottom line here is I have one very important task to do and that's find out the effective range and adjust from there. Without this information, everything else is just theory. I forgot which topic this is, can't see in Tapatalk when replying but if it's the FPS one, I'm only hoping it's not far under standard acceptable range (for the G27). If it's the one about barrels, everyone's information has given food for thought though I still do not believe it's just coincidental. Again, I have to redo the unscientific test at a greater range to see the full potential.

Great input everyone, thanks so much! Now if ASC will grant my AV sometime...

E-luder did you delete your message or perhaps editing? I'm certainly open to suggestions or criticism on testing effective range. I understand it can vary based on environmental factors but there should be a somewhat standard measure indoors where not much changes other than humidity.

Having said that, generally repeatable results is what I'd look for at a set distance. So, if my standard engagement distance in my fireteam is around 60ft, I'd be sure I can be accurate at tha distance. From there, I'd step back until the groupings or perhaps hitting a hanging pot fails too much. Add in an arbitrary margin of say 25% reduction in distance and call it a day -- or until the next test. That's all I've got for now :) I'm not going to go crazy and ensure the mags have warmers between shots, or only measure a mag after 3 shots to take the edge off. I would want to find the maximum accurate engagement distance -- deducting a healthy margin for repeatability. Anything more and I'd be chasing the white rabbit.

The standardized testing you want is not plausible.

You can't test under one condition and use the gun in another expecting the same results (unless it's something like an AEG)

Keep in mind, when you actually use these weapons, you'll be in a state of duress. Thus, the way you think from when you're in your testing environment will be different from when you're actually in a firefight. Sometimes, disciplines fly out the window when people are trying to communicate with you while you're trying to suppress. Things like the importance of a trigger pull/squeeze, precise target acquisition and grip registrations are all lost in the wind.

Hell, even the smallest environmental differences will skew your results from place to place indoors or not. Who knows. One place can be cooler than another or a sudden gust of wind from the ventillation fans (or just windy day) can all skew the BB's flight path.

Testing can only get you so far in terms of you're gun customization. It's all about real time use and how you operate the firearm during this time of duress. That's where you asses where (or if) you need to make modifications.

By what definition are you trying to convey when you say things like accuracy and range?

Every new player I encounter always have a misunderstood definition of the words in airsoft terms. This is not to say you are a "new" player per se but rather gauging where you've learned these definitions and how they apply to airsoft projectiles.

60ft range is attainable. It's not hard to do. However, I will advise you to think about that engagement before you actually get out there and try it and if that G17 is the right gun to use for that situation...

Similar, not exact. There will be a set of circumstances that allow for repeatable results (not the same). For example, firing at 20ft will give you repeatable results since many of the variables such as wind and such play a very small factor. Again, controlling the only thing I can control, and that's how the gun will react.

Luckily I'm trained to handle such situations and do deal with high stress, although I do not purport to be a professional marksman. Still, the goal is to ensure the tool is reliable and understand/tune it to the optimal zone (not maximal).

Erm, commented above. I should have looped it in. :)

These things I cannot control but as noted, given indoors, there will be a reasonable expected outcome at a certain range. I will be looking for that predictable zone. It's all about learning the optimal use and hence limits of the tools you are given.

Agreed. I need to know what it can do, before I can understand if it can do what I'd like it to do... and that's not to be a rifle :confused:

Simply put, I will look for the zone where I know the tool will perform according to a predictable outcome. For example, it is fully capable of hitting a pot sized object at 40ft. It may be able to hit most of the time at 70ft given manufacturing tolerances, but at 40ft it's just about a sure bet assuming the operator isn't intoxicated. For some folks new to firearms, it may be as little as 6ft, again I'm looking for that zone (not limit).



Being only CQB, I can estimate the engagement ranges fairly well. Also given the role in the fireteam I run unencumbered so even the MP5K is too large. Anyhow, less about what should be used, shall we? ;)

Think of it this way. I'm sure more experienced players know the limit of their weapon. That is, they can judge a mark and know whether in most circumstances if it can be hit. That's all I'm looking for -- a plausible 'distance' where I can still predict with accuracy it will hit the mark (outside influences notwithstanding). I'm not interested in knowing how absolutely far it can shoot if all I can hope for is hitting a barn-sized target :D

EDIT: Just to be clear, I'm not looking for anyone to tell me any magical numbers as that certainly would be absurd.

By the way you've worded your responses, it made it sound like you were trying to find a maximum of sorts.

..or what you need to do to hit a 70ft target as per your fireteam's standards.

If you're looking for an "optimal" range, then your optimal range is always point blank. No variables (unless you count malfunction as one) are rendered feasible. Or if you really want to go on looser terms, the closer the the target.

If you're looking whether or not you can hit a steel plate at 70ft or 80ft or any given distance that you'd like to hit, then that is something special to your case and your gun. No one can answer this question for you because no one has the same gun as you. Nor do they draw the way you do.

There's a difference between "hitting" someone and "accurately hitting" someone. Considering your proposed experience, I'm sure I don't need to tell you which one has the "best" point of impact.

The gun doesn't react any different than when you fire at a target from 70 feet away or 2 feet away. It still fires the same way and the projectile still exits the muzzle with the same muzzle energy if shooting one distance or the further other. The factors that can diminish one over the other purely external, which includes the operator.

If you want predictability and are looking for the "optimal zone" of performance, then stay within a range that you factuality know will hit a target. That way you don't have to predict anything. It's just a draw, acquire, pull. And there's already enough evidence in this thread that suggest what that range would be. ANd if you require more evidence, go out to a game shoot everyone you see. Whether near or far. lol. That should give you a clue...

the more younuse that gun, the more you'll learn how to handle it. that's about the most bottom line, boiled down explanation of all the "testing" you're about to do. And no one can argue that. this thread is purely based on an individual operator's experience. there's not much we can say...

You need to go out and play. Use different guns and face different situations. You have a good arsenal, try all your guns in different situations. You will learn quickly enough what can and can't be done.

If you worry too much about accuracy and repeatability, you will probably grow disillusioned with Airsoft really fast. You will find that in a lot of situations, especially in CQB, you just don't have time to aim all that well, the split second saved will make the difference, and over time, you will know where each of your gun shoots when you point it a certain way, even before your eyes can line up with the sights correctly. Over time you'll be able to do precise and fast reflex non-aimed shots at close range and start relying more on your sights at medium to long range. And remember, under stress, it is normal to miss a lot, even at close range. You will find that when playing with experienced player, they will shoot first, so you will pretty much always be shooting under stress. Over time, you'll catch up and maybe even surpass them.

While technically Airsoft guns are very accurate (we reliably hit corkscrews at 8-10m at MATS nights), there's no way any of us could pull that off in a game while being fired at.

So, enjoy the game first, and worry about tuning your guns later. You will also find that a lot of long time players play with stock guns. They are over worrying about gun performance and know what their own limits are. I often play with a completely stock Cyma Thompson. It shoots well up to 150-180 feet. That's really all I need. I learned that you are much better off closing distance and surprising your opponent than taking potshots at 200 feet with no guarantee of hitting and instantly revealing your position. That's one of the many tricks you will learn while playing.

Thank you e-luder and Drakker, I was going to quote your posts and have some further discussion but there is too much armchair chat (for/from) me. Remember, I'm not looking for any definitive proof on what my kit or I can do, just that I reported an interested phenomenon (to me) and was hoping for some validation past coincidence. However, as you both say in different words...

"Get the heck out and play!"

:)

To end, I'll quote some more notable words:

If you're only playing at siege, you don't need to upgrade your pistol to be honest.

Just play aggressive, rush often, and learn how to position yourself, that's how you'll land kills. You'll have almost no gear on you, and you'll have the speed advantage.

Not just Siege but at other fields I'll be using either the G36C folded or the MP5K.

Thanks for popping in the thread!

If you are not going to use the stock on the G36C then stick with the MP5K. Its smaller, more maneuverable and has smaller mags. But even better, use the G36C with its stock. Learn to maneuver in tight spots with the stock, and reap the accuracy benefits of a good cheek weld. I used to think like this too, I even used a folded AK105 for a while when I first started. It just doesn't work well. When I started working on my cheek weld (i.e. putting my head in the exact same spot every time, whatever my position (double parenthesis: yes, its harder than it sounds)) it made a world of difference. I suddenly found that my gun was very accurate and that I was the one that couldn't shoot for crap.

The only issue is the sight is too low for my mask. I either would go to a google/mesh combo or continue with the full face. I opted for the latter so a riser is on it's way. Once that arrives, I do feel the G36C will be my primary for those games with extended stock. I will practice the ready to shooting position to ingrain it to muscle memory as you say ;)

The problem with risers is that it get your sights/optics farther away from the barrel. This complicates things when sighting in your gun, as your visual line of fire is not the same as the gun's actual line of fire. They will meet each other where you sight them in, but at closer range your gun shoots lower, and at longer range it will shoot a lot higher. You can also sight them both to be parallel and compensate, which is the way I prefer it. But still, it is not perfect.

You'll experience it whenever you want to shoot someone through a thin horizontal opening like a palette. If you are close by, your weapon's barrel fits in the opening, but you can't see your target because your optics are above the slit, and if you are farther away, your line of sight is on the target just fine but the BBs will hit below the opening. This leaves you to shoot with your gun at a 90° angle, but then the hop-up prevents you from shooting at medium to long range.

This is another reason why I like my cheapo Thompson, the front sight is directly on the barrel, so I never have this problem.

Just get the mesh mask/goggle combo and save yourself the trouble.

Thanks for the insight. I did understand the difference in view but hadn't thought about the palette shot scenario. I do have a pair of ESS Profile and mesh mask combo but not really feeling for it. I've even cut it to fit better but not quite there yet. I suppose I need a helmet or hat... something to tie the pieces together in a unit. Luckily I do have a relatively healthy budget so I essentially purchased a sampling of many things to see what works for me -- then if the AV ever goes through, I'd sell off the other items or gift to my friends who are starting out as well.

I'm very happy with the responses and appreciate everyone taking the time to jump in!

When I talk about "effective range", what I mean by that is the range at which I am confident I can shoot a person center mass with high repeatability. The gun is effective at the range I'm comfortable being able to hit you with a minimal number of rounds.

My pistol, completely bone stock, using .32g BBs, had an effective range of 160ft.
Me personally shooting freehand with the pistol, maybe 80ft? But braced, I was getting 12" groupings at 160ft.

Don't get overly concerned with muzzle energy. The weight of the BB has more effect on range than it's muzzle energy.

For example; I've seen many a 1-1.13j gun out range a 2j sniper rifle.
Using heavier ammo, and being able to apply more backspin to the BB, will give a much higher range advantage than simply raising the muzzle energy.

For example with factual numbers; I "raced" VSR-10 builds with someone. We had the same cylinder, same hop rubber, he had a 550mm 6.01 barrel, I had a 430mm 6.03 barrel, he shot 470fps on .20s, I shot 380fps on .20s
Both using .30s, with an extra 0.7j of muzzle energy he was gaining a whopping 15 feet over me. However, he was less accurate at 240ft than I was.
Now had I been using .32s or .36s, I actually would have out ranged him, despite him having a 90fps advantage over me on .20s