Thanks guys.
The breech & barrel was made by Daq. He made just a few years ago.
The barrel that came with it was 10 inches & made by him.
I have only seen two that have ever gone up for sale, & they were both for sale at the same time!
I wish I would have bought the other one to!
Here is a pic of the 9mm pellets, they don't make them any bigger than this!

The pellet on the left is 77gr & the right one is 60 gr.
Well here is a up date on my 9mm co-2 gun, running on hpa 850 psi.
When I got the gun it was shooting at 324 ft/sec & 22 fpe shooting 71 grain lead ball.
Then change the stock 10 inch barrel to a 13 1/2 long one. & got 378 ft/sec.
Then I changed the hammer spring to a stronger one & when to 422 ft/sec.
Now I tried the lightest ammo for the 9mm which is 60 grain pellets in the 13 1/2 barrel & got 488 ft/sec.
And lastly I read that if you change the valve spring out that you can gain some ft/sec. I am using Bryan and Associates valve.
So after trying it about 15 times of taking the whole gun apart, it was my last time, I was giving up.
I tried a spring the same size, but half the strength, and guess what it worked.
I went to the first ever to 513, 504, 527 ft/sec & 37 fpe.
I gained 40 ft/sec from just the spring change!.
So between the hammer & the valve changes both has gave me a gain of 83 ft/sec.
I never would have guest it, that I could get that much.
but my chro. has told me so.
Here is a pic 000 buckshot I use 71 gr.

So then I bought a hammer adjuster from Art at:
http://www.arts-shack.com/brakes.html So I could adjust the spring pressure.
But it also let you use a stronger spring, to the point of without the adjuster, you would not get the bolt back.
Because by backing the adjuster it will let you close your bolt. Then the spring is not as strong, then you do your adjusting.
Now here comes the good part:
Now I went from shooting the 60 grain pellets from, 531, 535, 526 ft/sec & 37 fpe.
To shooting the 60 grain pellets 562 556, 560 ft/sec & 42 fpe still with only 850 psi.hpa.
And shooting the 77 grain heavy pellets @ 469,474,479 @ 39 fpe. 850 psi.
To now shooting the 77 grain heavy pellets @ 499, 496, 500 ft/sec & 42 fpe. Still using only 850 psi. hpa.
Anyone thinking of getting a hammer adjuster give Art a try, he does great work, and it’s good trick, I gained 21-25 ft/sec more power with the adjusters.
Was at 1300psi air 612, 615, 614 shooting 60gr pellets, & 50 fpe.
Now with reg. fixed at 1350psi 60gr. 644 ft/ sec, 649, 651= 56 fpe
Was at 1300psi air 77gr pellets & got 567644 ft/ sec & 55 fpe.
Now with reg. fixed at 1350psi 77gr. 595644 ft/ sec, 586, 600=61 fpe
Next in mods is a derlin valve stem, that should make the gun be over 65 fpe range.
So that is a build up of a 2250 crosman pistol, these mods will work on any cal 22xx guns.
And was a lot of fun doing the mods your self, & seeing the results with a chro.
that makes air gunning a great & fun hobby!