How to co2 bulk fill a Crosman 2240 2300 2250b 2400 pistol carbine

How to co2 bulk fill a Crosman 2240 2300 2250b 2400 ratty

Bulk filling a Crosman 2240/2250 isn’t that hard.

Several options possible. I’ll write about and show the way I converted my pistol and carbine. Links and parts list at the bottom.

Do not use compressed air, the system is built for self-regulating co2 and cannot safely handle higher pressure.

First got a CO2 extinguisher. These have a date after which they may not be re-filled anymore. The companies who supply them take them in and have to pay to dispose of them. Visit such a company, bring a bag of coockies and you may end up with a few co2 extinguishers for free. Worked for me.

If you want to fill your co2 bottle yourself you’ll need said co2 fire extinguisher and a fill station to attach to the co2 fire extinguisher + a hanging scale to weigh your paintball bottle empty and full. A regular kitchen scale will do the job too. Do not over-fill a paintball bottle.

A co2 bottle can be bought at any paintball store or at Euro Custom Parts which is Stuarts store, he’s Gmac’s son.
I use a 7 oz bottle w. on/off valve (7 oz = 199 gram)
Also available: 3.5 oz = 99 gram / 5 oz = 142 gram / 9 oz = 255 gram / 20 oz = 567 gram

How I fill my bottle:

First time weigh empty bottle and write down the weight on your fire extinguisher.
Write down the max weight of the co2 to be filled (7 oz = 199 gram) on your fire extinguisher.
Add both up and write that down too.

Outer lever of bulk fill station closed, inner lever open.

Bottle attached to fill station, on/off valve open.

Fill bottle a bit, open outer lever a while and let some co2 escape. This cools the bottle. Only a cool bottle can be filled completely.
With outer lever closed repeat filling procedure until you cannot hear co2 flow anymore.

Close the bottle’s on/off valve.

Open outer lever of fill station to let the co2 escape from the hose/fill station. Noisy ;-)
Weigh full co2 bottle.

If there’s a bit too much co2 in the bottle open the on/off valve and let off a bit and weigh again.

Never point escaping co2 towards a living creature to prevent frost bite!

Now your paintball bottle is full it’s time to convert the Ratty to bulk fill.

Undo the 22xx’es end-cap and remove the empty 12gr co2 capsule.

The Euro Custom Parts (made by Gmac Custom parts) Brass powerlet eliminater can be fitted with an elbow first, your choice. Wrap a double layer of ptfe tape around the elbow’s threads anti-clock-wise and screw it into the eliminater snuggly. Then screw the eliminater into the 22xx’s tube by hand. After that tighten the elbow w. a spanner making sure the exit hole is pointing down.

Screw a Quick Release Nipple 1/8 NPT into the elbow. (ptfe on threads)

Attach a remote line with slide check to the Quick Release Nipple 1/8 NPT.

Attach the other end to your bottle making sure the slide check is closed.

Open the on/off valve so the co2 can enter the system.

When done shooting close the on/off valve and dry fire a couple of times until the hose and valve are empty, after that the hose and bottle can safely be removed.

If your remote hose has a slide check there’s no need to dry-fire untill empty, spimply pull back the slide check to vent the co2 which is “trapped” from valve to slide check, an easy and quick way. Don’t forget there’s still co2 in the hose from slide check to bottle.

If you like to shoot your Ratty outdoors in the cold, tuck the bottle inside your jacket, the co2 will stay warm and usable.

Switching to High Pressure Air is a different story and involves more work, parts and safety precautions: beware !


Boards with usefull info:

Blog posts with usefull info:

Parts list

GMAC Custom Products section
2240 Powerlet eliminater
2250 Powerlet eliminater
2260 Powerlet eliminater

HPA & CO2 Fittings section
Remote Line with Slide Check
Male Quick Release Nipple 1/8 NPT
90 deg. Bend 1/8 NPT Male/Female
Nipple Dust Cap
Co2 Fill Station
Paintball bottle w. pin or on/off valve

Another supplier:

Rap4 pin valve 88 gr pin-valve adaptor for refilling an empty 88 gram disposable bottle

Hanging scale

Other vid showing how to fill a bottle:

Voor de Nederlanders: met link naar pdf met uitgebreide uitleg, geschreven door pjotrk (Pieter)

Post time: Dec-18-2016