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69Hotrod69 · Veteran Member

This started out as a 2400 and now is a 2260. I made some changes but before I did the tube conversion I was getting 907 FPS at 1800 PSI with JSB 18.1 gr pellets with a 1377 Hammer Spring. It now has a disco Hammer spring and I'll get some Chrony numbers soon. Very Happy

I'm really Happy with the way the stock feels, I actually need to lower the cheek rest just a bit and it will be perfect for the 32mm scope.

As usual I'd like to thank Rsterne for his awesome posts that helped me learn to tune these rifles and pistols. Bob, you really should write a book. Razz

Crosman140 · Senior Member

A beautiful gun! A piece of art.

And 33+ ft lbs of energy...NICE! Uzi Shooting

walter · Veteran Member

not that is a GORGEOUS piece of art! just beautiful! great job! thats got to put a hurting on the squirrels. Laughing

packrat · Senior Member

Right you are!!! Bob is truly THE MAN when it comes to Crosman 22XX stuff !! He's helped me inumerable times with all sorts of issues..
That gun there is super nice/clean....probably shoots even better than it looks..33fpe is awesome!!

broommaster2000 · Moderator

Yup, you're in the club too! Wink

yourdaddyjoe · Supporting Member

Ya got to at least post the pics in the Cool Kids Club... Mr. Green

broommaster2000 · Moderator

Well, that's the initiation, but I agree. Go forth and post dem piks!

69Hotrod69 · Veteran Member

I have had requests from members on what was done to build this rifle so I am going to now cover the details of this build.

Before I start though I believe its important to state that HPA is very dangerous and can cause severe injury or even death if misshandled, so you do so at your own risk. I have taken steps I believe make this build safe but you must make that determination for yourself.

I will do the build by sections starting with the stock:

It is a 1399 Crosman stock shortened one inch with a Morgan adjustable buttpad added this gives a pull of 13.75 which is perfect for my arm length( I measure from the pit of my elbow to my index finger held as though I'm pulling the trigger). I added an Advanced Technologies cheek rest(UCR-1900) on 1/2 aluminum risers to get the right heighth for the scope.

It is very comfortable and alows very quick target acquisition.

69Hotrod69 · Veteran Member

Next I'll cover the power plant:

The tube is a 2260 tube drilled out to except the Discovery valve, and the Muzzle Mack Gauge block. I honed and polished the inside tube to a mirror finish.(helps with hammer momentum and tube strength). Tube is very carefully deburred all holes and slots. I used a stock tube cap with a 6061 T6 aluminum slug with 2 oring grooves to seal the tube, looks good but I switched out later for a readily available discovery end cap plugged with a high pressure stainless steel 1/8th pipe plug.

The 13CI Ninja bottle was modified with cup washers from McMaster-Carr and shims to get an even 1600psi from the regualator. Every regulator is unique and requires a test rig to set properly. Their are exsisting posts on how to do this. The outlet pressure is protected by a 1.8k burst disk(very important for safety! if regulator fails the rifle will be subjected to 3kpsi if the burst disk is not used! so I allways use proper burst disk for the rifle being built!). The bottle is atached to a UPZ legion ON/OFF ASA valve and a High Pressure Stainless Steel Nipple From Mcmaster-Carr which is then atached to Muzzle Macks Gauge block. I used a discovery valve to keep a track of output pressure.

The valve is a Disco valve heavilly modified, the threads were shortened to .4 on the Muzzle Mack bulk fill adapter( this is a must to bulk fill the 2260 tube, it puts the sealls ahead of the rolled stamped area reducing the risk of tube failure). The valve was bored out to .600 I.D. the valve port was angled to 20 degrees and then drilled to .161 The inlet chamber was drilled to .238 and the inlet corner rounded all surfaces polished to mirror finish. . The stem was narrowed to .115 for the first .4 from the valve seat. The seat diameter was reduced to .400 and shortened to .275. This is the same as rsterne has posted in his 22xx PCP buld.

The Hammer was polished to a mirror finish and a disco 1377 spring was used in conjunction with an RVA from rsterene.

69Hotrod69 · Veteran Member

Finally I'll cover the barrel and Breech:

The breech is a long steel breech for a 22XX with a Discovery 22cal bolt and handle.

The barrel is a 2260 barrel that I polished the inlet, drilled port to .169 and gave it a target crown. I topped it off with a Muzzle Mack brake.

domer_pyle · Senior Member

Very nice. I wanna see the damage that thing does on live game, especially sparrows, starlings, and grackles!

NoBull60 · New Member

I really like what you've done with your air rifle. Impressive! I would love to know where you found the stock. The adjustable feature is a option that I've been looking for. Great looking air rifle.