Is a Boss valve "wasted" on a 2240 with a 12" barrel?

[Bark-eater]

I have a 2240 I built up about 15 years ago. Its got a 12" 1322 barrel and I think the only thing I did internally is to shim the hammer spring with an air soft BB.   Its been very effective inside 30 yds.

Unfortunately its leaking so its time to take it apart. I have a Crosman power adjuster in my parts bin and was thinking of ordering an upgraded "Boss" valve and transfer port from one of the venders.   

My question is whether this is worth while with a 12" barrel?  My hope is that I would gain "energy" through efficiency and be able to use the power adjuster to throttle down to where I'm not wasting gas.

Or am I going to hit diminishing returns over the stock valve and porting with the 12" barrel?

And if it is a fine idea, are any of the various plug and play modified valves and transfer ports  better suited to this project ?

Thanks, Woody

[CraigH]

There is going to be a lot of gas wasted and attendant increase in noise.  To gain efficiency use either a SSS (Short Stiff Spring), or an SSG (Stopping Spring Guide) device.

The ideas is to open and close the valve quickly - i.e., close the valve before the pellet leaves the barrel.   Large equalized (valve, TP, and barrel) porting may accelerate the pellet quicker, but the valve must be closed to increase efficiency.

Here is a topic from a few years ago.   The carbine first used a spring of 0.042" diameter wire and 1.5" length.   It was converted by the use of an SSG which it the subject of the topic.

https://www.crosman-air-pistol-owners-forum.com/board/index.php/topic,18770.msg235753.html#msg235753

Considerable tuning opportunities are possible with an SSG - spring rate, spring length, spring preload, free-flight gap.

[Mike660]

Alchemy Airworks had a RP High Performance valve that works like the Boss valve but better in the shorter barrels. You can text/email him with any questions. He also has them up on EBAY

http://www.alchemyairwerks.com/store/p11/Alchemy_AirWerks_Rally_Ported_Higher_Performance_Valve_for_22xx_Crosman_CO2_Air_Guns.html