CO2 2240 Frankengun now a PCP

Jump to latest Follow Reply
T3PRanch

T3PRanch

Member
Apr 22, 2016
2,939
95
Post TX, United States
www.t3pranchags.com
1561951743_11863543685d197dff771a35.38674192_2540 Franken Gun.JPG


Well my 2540 Frankengun project is nearly complete after several years of morphing from one form to another.

Base Gun was a Crosman CO2 2240

Parts added:

Baker Airguns Big Bore Breech.

10" LW .25 Heavy Barrel home machined from a piece left over from a fitting of a 24 inch barrel to an AirForce TalonSS which only needed a 12" barrel.

Custom Nylon Rear Tube Plug for stock 2240 tube.

Hammer Spring from an OLD (30 year) Sheridan PMI Paintball gun

1/2-20 threaded Barrel Adapter from Best Fittings in the UK

Home made Moderator stuffed with AirForce SS Baffles and made from 1" Gloss CF Tubing 

AirForce 11mm Riser Rail

OLD and I do mean OLD (39 years) Bushnell Pistol Scope with 2.5X attached power booster.

UTG High Rings Law Enforcement Grade.

Home made stock from a member of this forum. Do not remember who!

Baker Airgun Max Flow System for Crosman 22XX (Valve and Bulk Fill Adapter) 

1/8" PB Foster Male Nipple for Bulk fill adapter (Bulk fill has a integral check valve)

AirForce 3K PSI 500 cc Bottle

E-Bay Chinese Regulator set for 1200 PSI output

AirForce Braided Airline and REAL Foster Brand Female Connector made for a AirForce Pump

E-Bay Paintball gun Valve for Regulator output

Harbor Freight Zip Ties for Temporary Attachment of Bottle to Stock.

This converted a 10 yard .22 CO2 gun to a 35 Yard .25 PCP Gun and it's accurate too. Pellet on pellet with the side of a tree trunk for a rest.

Effective to 50 yards with little pellet drop using JSB Kings at 25.4 grains.

I might go to a 350 cc CF Bottle later since the regulator is rated for 4500 PSI input. and the bottle would be 4350 psi

It ain't necessarily pretty but I have seen far uglier! ;)

Yes it cost more than some low end factory PCP's but the ride was where the fun was on this one. I had a LOT of parts from other stuff to use that were not made to go together. Fitting together unrelated parts into a new "tool" is a joy to me!


 
Picture is a bit hard to see the tube, but I'm not seeing any valve screw. Did you add any screws to secure the valve? If not then I would not consider that a safe build with PCP.

Not using additional valve screws is the main reason for the guy with the HiPac getting the valve shot into his leg. Of course he attempted to disassemble with the gun pressurized, but not having the additional screws allowed his valve to move and when he removed the trigger guard screw, which was actually partly holding the valve, it allowed the single valve screw to finish shearing off, releasing the valve and sending it thru his leg.
 
Upvote 0
1200 PSI is well within specifications for CO2, however the surface bearing pressure is greater. I will probably add more or a bigger attachment screw even though Baker does not drill the new valve for any additional attachment screws. An additional safety is that the gun is only pressurized during use. The valve to the regulator is closed at all other times.
 
Upvote 0
1200 PSI is well within specifications for CO2, however the surface bearing pressure is greater. I will probably add more or a bigger attachment screw even though Baker does not drill the new valve for any additional attachment screws. An additional safety is that the gun is only pressurized during use. The valve to the regulator is closed at all other times.
Click to expand...


Good idea, not sure why Baker doesn't do that. Personally if the valve screw were to fail I would rather it fail while the gun is standing up in a corner of the house as opposed to when a person is sitting behind the trigger.

Here is a good read from a few years ago (different forum). Just remember too, if the regulator fails you now will have close to 1800psi before the disc blows. If it gets to 1700 and the valve screw fails then the valve will become a projectile and the burst disc will likely not give.

https://www.gatewaytoairguns.org/GTA/index.php?topic=97198.0

I did a similar build a while back but I used the stock 2240 valve and drill/tapped the nose 1/8npt and direct feed the bottle into the valve so the tube is not pressurized. Even so I still drilled and tapped the valve for better security to keep the valve aligned with the TP.

I've even got a spare one of the chrome dropdown ASA'a like on my gun if you want it. It's got on/off plus 2 ports, one for line and another for gauge. If you want it just let me know I'll send it to ya. (I think it makes for a bit nicer attachment then zip ties)

1562016067_6799553915d1a794332f4e2.44287311_20190701_171703.jpg

 
Upvote 0
1564094657_17765673445d3a30c1445880.04860949_P7250213.JPG


Finished Stock with Bed Liner and added an extra 300 bar CF Bottle to the ASA BTB provided to me. The stock is now 2 piece due to the less than pencil sized center section snapping on me.

Chrony readings will be next. Useful range has gone from 10 yards with the original 2240 CO2 version to 60 yards with the 1200 PSI Regulated .25 PCP version.

Accuracy shooting with a vertical pole for a steadying device in a bit of wind looks like around 1" (3 shot group) at 60 yards between wind gust of 12 mph! I am using JSB 25.4 Grain pellets!
 
Upvote 0
You must log in or register to reply here.
Top Bottom
Back
Home
Forums
Resources
Menu