Top velocity for a 1322 with mods

[Cosmic_Charlie]

I got a beefed up pump linkage for mine in conjunction with a flat piston an valve. I also put a lighter spring in the valve so I could run a lighter hammer spring which improves my modded trigger's pull. I also decreased the valve volume so it builds pressure faster with fewer pumps. I have not chronographed it in awhile but it kills head shot rabbits and squirrels cleanly. It is also very accurate which allows head shots on pidgeons. Best of all, with a homemade can it allows all this in town

[thunderthud]

a Diana LP8 will get you well over 650 fps . its a break barrel springer. advertised at 700+. its a beast. I have a Air Force Condor ss in .25 1100 fps no problem for my max horsepower.

[UnimatGuy]

Thought I'd revive this thread
Hi Ive modded my 1322 quite a bit.
Flat top piston etc
steel riser breech floated recrowned 14.5 barrel
valve smoothed, lighter spring volume added
with 14.35 jsb exacts
At 5 pumps 460
7 495
10 544
15 590
16 610
It's one of the 1980 "medalist" .22 models with the rear cocker.
Just recently finally got a chrony was surprised by the numbers
I like that I am getting 10 pumps worth of stock fps with only 5 pumps and only a 14.5 barrel. It shoots one hole groups at 10m on a rest.
It is however going to be returned to "stock" form retaining all FTP etc and into the stock pistol barrel and grips that will tame it quite a bit.

[Ramson222]

Thought I'd revive this thread
It is however going to be returned to "stock" form retaining all FTP etc and into the stock pistol barrel and grips that will tame it quite a bit.

Why are you returning to stock form? seems to be a great gun. I wish I still had my custom build that would do 580 with 12 pumps.

[UnimatGuy]

Why are you returning to stock form? seems to be a great gun. I wish I still had my custom build that would do 580 with 12 pumps.

Don't like pumping , love my hand made stock for it, so am going to build either a 2260 based co2 or pcp powerplant for it

[The Grump]

I don't have a chrony, but I recently received my 1300KT from the custom shop (long steel breech and 10" barrel) and immediately installed the power modded valve by Alchemy, along with the heavy hammer spring and enlarged transfer port, and I can tell you that at 15 pumps it packs a wallop. With 20 pumps, it throws an 18.5gr Barracuda Hunter Extreme a lot faster and harder than my stock 1377 at 10 pumps using 7.5gr pointed tips. It dumps all of the air I put in it, and at 17 pumps, which has become my regular charge, it's a tack driver.

I don't usually bring it up to 20, because I'm not shooting further than 10 meters at rats, and I didn't want a long barrel because I like being able to put it in my back pack or bike bag and take it to friends' houses to go plinking. However, I did want it to keep up and surpass my 1377 in all respects, and except for pellet costs, it does so, except in accuracy, which I'd say it's pretty well equal to, as long as you account for the recoil, of which this thing actually has a noticeable smidgin. Not a lot, but enough to throw your shots high if you don't account for it in your grip and follow through. It's actually the first time I've ever come across an air pistol that does.

Don't mind they nay-sayers, go ahead and put the juice in that puppy. Just be aware that with that power increase, those pellets with either penetrate deeper, or ricochet harder. Some (many?) of the things you were just putting dents in, will now have holes. Stay safe, have fun, and use eye-protection.

Edit: Follow-up. I've been pumping this thing up quite a bit, and even at 50 pumps, she's STILL dumping all of her air with Crosman hollow points. At 25, she'll pierce a car windshield or a raccoon's skull at close range. I have her zeroed at 20 pumps, and that's what I generally use as my standard charge, at this point. I think the high-performance valve that I have from Alchemy Air has a larger internal volume, so it takes more pumps to bring the pressure up, but it will hold and dump more air. At 40 pumps, the hollow points won't pierce a road sign at 10 yards, but they'll get most of the way there, and leave a very clear raised point in the middle of the rather large dent (compared to 20 pump impacts) from the hollow point's shape. I'm going to pick up some H&N Hornets today, and see if I can't make it through some signs that are in my warehouse. (I didn't pilfer them, they've been here for years, and I don't condone vandalizing signs in current use, or anything else, for that matter.)

In spirit of full disclosure, all of these recent tests have been made after replacing the barrel band with a GMAC threaded band, and a silencer of my own making, from a 1" diameter aluminum tube (repurposed from a dead flashlight), 0.5" nut, a washer (as a stabilizing plate), using cardboard wipes (the corrugations help bleed off the air, and dish-sponge (with brillo backing to keep the sponge from being sucked out behind the pellets) plugs between them (to physically dampen the concussion of expanding air leaving the muzzle). It's about 5 inches long, with about 3 inches of that occupied by wipes and plugs, and the other 2 inches (1 in each end) to allow expansion and create a bit of turbulence to brake the concussion.

The muzzle noise is reduced a surprising amount, but the pellet's velocity has been affected as well, albeit minimally, and once broken in, and correctly stabilized and aligned, the effects on the zeroing are pretty much non-existent. On or off, this thing is still a total tack-driver. All that said, being quiet does come at a cost, but not enough to forego the silencer's use, and I figure since it will pretty much always be in use, that is how I should test it. It comes off easily for transport, and any weight it might add to the barrel is unnoticeable.

The addition of the aluminum barrel band has also increased consistency and accuracy. Needless to say, the local rat population has been significantly reduced, and those I've not yet bagged no longer conduct themselves in such a brazen manner.