Is a longer barrel more accurate?

[tunabreath]

Can o' Worms opening time.

I'm just curious what people think about this. I'm fairly certain that Canadian airsofters in general have always held that all other things being equal, a longer barrel should be more accurate than a shorter one.

That said, any time I look it up, the 'official' answer is always that no, there is no correlation between barrel length and accuracy. There was a test done in the UK some years ago that demonstrated this, but it was discredited on the basis of the AEG used being fired by hand instead of in a gun vise (among other things).

Still, it makes you think. Everything I've read indicated that a stiffer barrel is more accurate, which means that a short and fat barrel should be more accurate than a longer one of the same thickness (like all AEG inner barrels). Additionally, the in-barrel time for a longer barrel is obviously longer, which for unsupported firing would mean further accuracy loss.

Now, I have a TM AUG with a PDI metal hopup chamber (the one with the locking screw, so you know it's stable) and a KM V-hop bucking. I like to think that they make the gun more accurate, but practically speaking, I can't really say that. More to the point, I regularly swap between a PSG-1 length HBAR (6.04 KM TN inner) and a P90 length Para (stock TM cut down) setup, using the same hop-up components. Again, from a practical standpoint, I don't really see an improvement in accuracy.

I haven't taken any numbers down, so by making this thread, I was hoping I could find someone who has. Has anyone here done recorded tests using identical setups save barrel length?

edit @Cortexburn: Not really, but again, I haven't taken any actual measurements. One could assume that there's a slight increase in range from the fps boost that having a longer barrel gives. Also, I have a stock unported cylinder in my mechbox, which while fine for the PSG-1 length, is probably not ideal for the shorter P90 length.

[Cortexburn]

During these barrel swaps ( between the PSG-1 length and the P90 length ) have you seen any increase in effective range?

[Amoki]

If you haven't read Madmaxx's thread on Inner Barrel length matching with Cylinder Type, basically

1) When you barrel is matched to the type of cylinder you have, you'll always get good accuracy because the output volume of air (from the cylinder) will always be allowed to fully develop and stabilise within the inner barrel before it leves.

2) after a certain critical length, no matter how long your inner barrel is you will not increase the accuracy any more (though FPS will increase)

[Mr. G36!]

When I went from a G36C to a full-length G36, I noticed that the BBs fly straighter longer, though that could simply be the result of increased FPS. The accuracy itself isn't much different, but the BBs are more stable at longer ranges, and don't pull to the sides as much as they used to. But again, that could just be due to a higher FPS.

[ThunderCactus]

I maintain that it's the quality of the barrel, not the length, that matters.
My VSR get the same range and accuracy with 480mm that Amos gets with the 554mm barrel
My HFC M9 with its 100mm stock barrel outshoots stock M16's with 509mm barrels
And my UMP with its 205mm barrel got wicked range after I upgraded the cylinder set, I don't think it could have shot any further