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ray1377 · New Member

You fellows got any thoughts on this subject?
I've been doing alot of reading and it seems the worlds best springer, aka the AA TX200 has a barrel length of only 9.5 inches.
Wouldn't it be nice to have a short barreled Storm XT to carry hunting and plinking through the woods?
I read someplace else that most pellets fired through a springer reach their maximum velocity in the first 6 to 9 inches of the barrel.
Any thoughts or ideas?
Thanks
Ray

AirGunEric · Site Admin

Hello:

The "world's best springer" is an opinion- so right off the bat the theory is skewed.

The TX200 is designed to work with the rather short barrel- the compression tube is sized at nearly twice the length of the barrel- i.e. the amount of air it can move is presumably matched to work with its barrel.

Any airgun, no matter what power source, needs to match the air volume it is moving to the barrel length for optimum power production or other shooting characteristics (i.e. smoothness and the like)- the TX200 is one way of doing it, but does not necessarily make it the "best" or "better".

Any barrel (i.e. any length on any type of gun) can produce it's optimum accuracy results with as little as a few inches of barrel if the rifling is correct, but the propellent (air or powder or whatever) should be matched to allow for as little waste as possible for decent shooting characteristics.

If someone is using the TX200 as a model- it's tube sizing should be studied as well to determine the overall situation, but just chopping the end off another rifle's barrel is not necessarily going to work, and may in fact produce exactly the opposite of the intended effect- i.e. a less powerful, difficult to control gun.

Alstone · Moderator & Site Supporter

Has Eric says the TX200s insides are made to match the barrel length 9.5" for the HC (Hunter Carbine) version, the standard tx200 has subtle changes to compensate for the extra barrel length but they both perform very much the same. The shorter barrelled HC is better in heavily wooded areas.

Al

Slavia · Moderator

The barrel on my HW97K is 11.8", and it shoots pretty straight. If you look at different springers, a lot of them are in the 15" - 19" range.

I think the reduced sight radius of open sights on a very short barrel would limit accuracy, in spite of the inherent mechanical capability of the barrel. On the other hand, getting the pellet free of the muzzle before the shooter can flinch off target might be an advantage. Muzzle displacement from barrel harmonic vibration might also be improved.

This sounds like a project for someone with a gun (or barrel) that they're willing to destroy. Whack off sections at specific intervals, collecting group and velocity data for each barrel length until there is just a stub left. It would probably be good to express those intervals not as a linear measurement but barrel volume as a percentage of powerplant swept volume.

I have shortened the barrels on three guns, but no more than a few inches. Velocity stayed roughly the same, and accuracy improved. The two B3's were for aesthetic reasons. The Crosman Titan was an act of desperation, since every other effort to get it to shoot straight failed. I can't say the change was related to barrel length - it could just as well have been the removal of manufacturing irregularities in the last few critical inches of bore.

Then there's my Slavia 631 at 20.8" plus brake. It's long enough to be ungainly, but I'll put up with that. It's accurate enought that I would never consider messing with barrel length.

ray1377 · New Member

But I must confess.
I used the "best springer in the world" caption because thats what AA and most catalog outlets name the TX200.
I didn't mean it was the best. I've only shot one and it was nice, but I didn't get to shoot it enough to really get the feel of it.
The shorter barrel on my Storm was an attempt to get the pellet out of the barrel "before" the piston reached the end of the compression stroke and moved the gun during its rebound. Thereby helping or aiding the accuracy some if thats possible.
I have read alot that some springers reach maximum velocity in the first 6 to 9 inches of barrel. So to me that sounds like the rest of the barrel past that point is needless.
And I agree, the only way to really test this idea is take a springer and start cutting off the barrel, say a half inch at a time and chrony it between cuts to get a FPS reading.
I just was hoping that as much as this seems to be talked about somebody would have already tried that experiment.
THanks
Ray

Bob La Londe · Veteran Member

dcw · Member

i think one of the biggest reason manufacturers install longer barrels on BREAK ACTION air rifles is for ease of cocking.

air pressure inside the barrel when the pellet is travelling towards the muzzle is diminishing, whereas in a PB it is EXPANDING. the farther the pellet has to travel INSIDE the bore, the more speed is scrubbed off by friction.