Air Gun Home :: View topic

walter · Veteran Member

i was wondering the effects a barrel lenght has on pellet accuracy and velocity if any. i shoot a crosman 1377 now with plans to get a better rifle soon. bsa or beeman. thanks for the help. walt. Smile

rsterne · Moderator

A longer barrel has NO effect on accuracy.... but they will generally increase the velocity.... more-so on guns which are higly modified and putting out more power....

Bob

walter · Veteran Member

thank you. walter

Bozo · Veteran Member

If you're using iron sights, a longer barrel can enhance your accuracy by allowing more distance between the front and rear sights, or, by making the gun more muzzle heavy, it may help steady your hold; it doesn't make the pellet fly any truer.

packrat · Senior Member

If you do some research, you'll find that most of the higher end airguns, known for their laser-like accuracy, use anywhere from 14" to 16" barrels. I don't know if those are considered "short" or not, but it is what the majority of them use. One has to figure that they know what they're doing Mr. Green

IMO the longer barrels take away from the looks of a good many rifles, and they definitely add (unnecessary) weight and change balance point.....just food for thought Smile

walter · Veteran Member

but the hw97k has less than12 inches. super short. Shocked

AirGunEric · Site Admin

I suspect that specification on the HW97 is actually a mis-print that keeps getting repeated, or the "barrel" itself ends far before the end of the brake on the muzzle. Look at a picture of the HW97- at the front of the loading port is where the barrel will start, and if we assume it goes almost completely to the end of the muzzle brake, the overall length of the rifle would have to be 30", not 40"- so something's funky about this measurement/where the 'barrel' actually sits.

Anyone around here have a 97K they can measure?

Dukemeister · Member

rsterne · Moderator

That makes the 300mm claimed on the Weihrauch website pretty accurate!....

Bob

Mar · Veteran Member

It's all in your mind...look at pisols, look at rifles...what does that say?

Unless there's a problem somwhere along the line.

rsterne · Moderator

All I can tell you is that Weihrauch list the same muzzle velocity for all the HW77-97 series.... regardless of barrel length.... and the barrels vary from 11.8" to 18.5".... Shocked

Bob

fritz · Silver Status Member

If you use the same powerplant in a springer, wouldn't the longer barrel actually lower the velocity due to friction?

Also decreasing the theoretical accuracy because the pellet spends more time in the barrel, thus it is influenced more by the movement of the action in the time taken between trigger pull and exiting.

Accuracy is more dependent on the barrel quality and pellets. A good crown and throat will do a hell of a lot more for accuracy than increasing/shortening the barrel.

rsterne · Moderator

I'm sure that there is an optimum barrel length for any given gun, be it springer, CO2, pneumatic or PCP.... I've seen evidence that it would also vary with pellet weight & fit, temperature, etc.etc.... I know for certain it depends on the state of tune of the gun (possible exception a springer).... ie if you make the gun more powerful, you will benefit from a longer barrel.... It also varies with the caliber (again, possible exception for the springer) where the smaller caliber usually means that the optimum length will be greater on the same powerplant....

In terms of accuracy, at least in theory.... the shorter a barrel the better as there is a shorter period of time between when you pull the trigger and the pellet leaves the muzzle.... That means less time for you to wander off target, or for the recoil to move the gun (springer or not).... In addition, shorter barrels are more rigid, and hence flex less during the shot cycle.... If the barrel is so short that most of the air blast isn't driving the pellet but just acting to upset it as it exits the barrel then of course you are creating another problem.... Once again, there is probably an optimum length for any gun....

Most of the reason that long barrels got a reputation for better accuracy was that with iron sights, the sighting radius is longer.... meaning you can point the gun more accurately.... The same thing occurs with a high powered scope at long range when you can simply see the target (and how far you are off center) better.... It's not an accuracy issue, it's a "pointing" issue....

Bob

packrat · Senior Member

THAT right there may be what's keeping ne from being a "crack shot" the pointing problem Mr. Green

Alstone · Moderator & Site Supporter

The Air Arms TX200 Hc (Carbine model) has a 9 1/2" barrel and the standard TX200 a 13" barrel, both use the same internals and the difference in performance is minimal.

Al