For those of you that have been following my development thread on the 2240 - 2550, with the Extended Valve, and have been wondering where it was leading.... here is the answer.... Now that I have a much larger valve, and the ability to develop enough power, I can get on with the project I had in mind originally.... a non-PAL pistol (ie under 500 fps) in .25 cal, followed by .300 cal and .357 cal until I run out of available power (which may very well be at .25 cal, only time will tell).... I wanted to incorporate the MRod self-indexing .25 cal magazine, which thanks to Lloyd at AirGunLab, is also available in .30 cal.... and because I'm right handed I wanted a left-hand bolt action so that I can maintain my grip while cocking the gun and feeding another pellet.... I also wanted to use a Center-Point 32mm Reflex Sight, but they fit on a Weaver rail, so having a Weaver mount on the breech was part of the project as well....

I spent about half a day designing and making the Weaver mount, which bolts on top of the forward section of the breech, and then two full days machining the breech and bolt.... Here is the result....



The two holes right at the edges of the Weaver rail are to access the 4-40 screws that locate the front of the breech, and the hole behind them is to access one of the two barrel setscrews, so I never have to remove the Weaver rail from the breech.... The breech is made for a 1/2" OD barrel, and will accept a .25 ACP barrel, plus the .300 cal and .357 cal barrels that Sean Pero and I came up with and Sean is selling.... All the barrels will carry an internal O-ring, sealing on the caliber-sized straight nose of the bolt, which seats the pellet past the transfer port and then retracts into the "J" slot so that the transfer port is completely unobstructed.... I used this setup on my Disco Double, and I really like it, so I decided to incorporate it into this pistol build....

The main tube is from a Crosman 2250, using the Extended Valve and lightweight hammer, driven by a Disco hammer spring adjusted by a Challenger RVA.... The valve was opened up to a 1/4" throat, and the 5/16" OD Teflon transfer port is 7/32" ID, with barrel porting to match.... The main tube and the breech are drilled 5/16" to accept the transfer port, and I added a 6-32 tapped hole between the two 4-40 holes in the main tube for a larger central mounting screw to make the breech 100% rigid.... The MRod magazine will need a small clearance notch in the left side ridge on the bottom to clear the head of the screw which protrudes slightly.... Here is what the gun looks like, assembled but without a barrel....



I'm pretty excited to see how far this project can proceed before running out of power just using a 12 gr. CO2 cartridge, and staying within the 500 fps Canadian non-PAL limits....

Bob