Alecto longer barrels

[Taylor]

According to Webley the Alecto has a maximum muzzle energy of 5.8 ft/lbs meaning as little as an extra 10 fps with a 7.5 grain pellet is enough to put the pistol into the same category as a prohibited handgun.

Adding an extra 3.5 inches of barrel will increase muzzle velocity because the compressed air has more time to act upon the pellet (the physics are different for a spring-piston).

10 fps isn’t much to play with. Some owners will always be responsible with modifications, others won’t give a stuff and may even want a more powaful pistol.

With a Home Affairs select committee deciding the future of airgun legislation - including representation from the GCN who no doubt monitor this forum - now is the time for that little bit extra collective responsibility I think.

[Mr. Gain]

According to Webley the Alecto has a maximum muzzle energy of 5.8 ft/lbs

Whilst I agree absolutely with your line of argument as regards responsible behaviour, I'd be cautious about accepting Webley's claims for the Alecto as Gospel. I mention this because the most I can wring out of my .22 Alecto is 5.5 FPE. The margin is still narrow, I admit...

[Monkeyboy]

Has anyone actually tested these longer barrels yet to see if it does make any difference?

My .22 alecto with 3 pumps gives 4.9 - 5.2 ft/lb with 16 grain jsb's (25 tested with f1 chrony) I don't see that a slightly longer barrel would put it over 6ft/lb.

I know a few people who have added longer or shorter barrels to their guns and it's made little or no difference to their velocity, but every guns different I guess.

[BigEars]

According to Webley the Alecto has a maximum muzzle energy of 5.8 ft/lbs meaning as little as an extra 10 fps with a 7.5 grain pellet is enough to put the pistol into the same category as a prohibited handgun.

Adding an extra 3.5 inches of barrel will increase muzzle velocity because the compressed air has more time to act upon the pellet (the physics are different for a spring-piston).

10 fps isn’t much to play with. Some owners will always be responsible with modifications, others won’t give a stuff and may even want a more powaful pistol.

With a Home Affairs select committee deciding the future of airgun legislation - including representation from the GCN who no doubt monitor this forum - now is the time for that little bit extra collective responsibility I think.

Wouldn't that be negated a bit by the fact that the pressure of the air will be lower in a longer barrel as the pellet reaches the muzzle end?

[Taylor]

Wouldn't that be negated a bit by the fact that the pressure of the air will be lower in a longer barrel as the pellet reaches the muzzle end?

Eventually, yes. There is a point where increasing barrel length swings the opposite way and causes a decrease in velocity.

It’s also a myth a longer barrel automatically means better accuracy. It doesn’t.

Further explanations here
http://airgun-academy.pyramydair.com...barrel-length/
http://www.pyramydair.com/blog/2005/...important.html
http://www.pyramydair.com/blog/2007/...locity-in.html

[Mr. Gain]

My .22 alecto with 3 pumps gives 4.9 - 5.2 ft/lb

I don't know if mine's typical, but it actually generates less power with 3 pumps than with 2. Three pumps gets me about 5.1 FPE, as compared to 5.5 FPE with two.

[PaulR]

I don't know if mine's typical, but it actually generates less power with 3 pumps than with 2. Three pumps gets me about 5.1 FPE, as compared to 5.5 FPE with two.

Sounds like a fault to me - there is a release valve that will not allow overpressure, you can hear it hiss on the third pump - seems like yours releases too much.

You could try slowly and surely compressing the third stroke - the temptation is to slam it back because the resistance is greater with each stroke and maybe this causes the valve to react.

[Mr. Gain]

Sounds like a fault to me - there is a release valve that will not allow overpressure, you can hear it hiss on the third pump - seems like yours releases too much.

You could try slowly and surely compressing the third stroke - the temptation is to slam it back because the resistance is greater with each stroke and maybe this causes the valve to react.

Agreed. The release valve definitely activates on the third pump, but it does so regardless of how quickly you close the top cover.

I'm not bothered by this. Most of my shooting is done with just the one pump anyway, and 5.5 FPE from just two is plenty extra for those times when I want to shoot a little further or knock down targets with a bit more inertia.

[Monkeyboy]

Well I have tried to contact this guy making the barrels and had no reply for a few days so looks like it's a poor show anyway.

[Bob.]

I don't know if mine's typical, but it actually generates less power with 3 pumps than with 2. Three pumps gets me about 5.1 FPE, as compared to 5.5 FPE with two.

Mine gives 5fpe with 2 pumps, and 5.2fpe with 3 pumps. That's why I never use 3 pumps....hardly worth it for all the extra effort!

Bob.

[BigEars]

Eventually, yes. There is a point where increasing barrel length swings the opposite way and causes a decrease in velocity.

It’s also a myth a longer barrel automatically means better accuracy. It doesn’t.

Further explanations here
http://airgun-academy.pyramydair.com...barrel-length/
http://www.pyramydair.com/blog/2005/...important.html
http://www.pyramydair.com/blog/2007/...locity-in.html

Gets ya a bit nearer the target, though.