Crosman 1322 project, 90% of everything i wanted

The stock configuration we all know. The numbers of the left column are completely stock right out of the box. The right column is after adding a flow through bolt. Makes no difference in fps. The slight drop I would attribute to having just oiled everything prior to the left column and may have gotten slightly more from the pump cup. The bottom numbers are after adding a hammer spring adjuster and .038 spring. Each number 1-10 is that many pumps for each reading. You can also see a slight jump in the db rating.
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after adding the steel breech, and enlarging the transfer port it gained about 4 fps. Not a hard mod to do with a little effort.
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you will need to drills. 1 to clamp the port in and the other to drill it out. The bit must be freshly sharp.
The hammer spring adjuster is made from the original cap, and a bolt from the hardware. This 1 is a bit more challenging to make if you are me and don't have a lathe.
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you will also need that shim, or shorten the existing mounting bolts at back to be able to turn the adjuster freely.
I added a flat top valve, with adjustable piston. Also added a bearing inside the valve to take up space and increase pressure with each stroke. While the gun was apart, I swapped out the barrel band for 1 with a 1/2-20 thread made from aluminum. Has 3 grub screws to secure the barrel, and also allows for centering so you don't get any pellet clipping on the way out. I did have to chase the threads due to poor quality control, thank you China. Zero poi shift on or off. Now with reduced air volume, and silencer it is under 93 db. Also more weight forward and balances better while aiming with the red dot.
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It's quieter and almost at the same fps as before but with 8 pumps instead of 10. All fps numbers taken with cphp ammo.
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putting this over factory fps specs of 460, and doing it with less pumping, and less noise.
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Feels like win to me. Specifically designed with sparrow control in mind. Should be more than enough.
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Best bit of advice I can give you. Order a small bottle of Mac 1 secret sauce. Basically industrial hydraulic fluid. Use it on the pin for the piston, pump arm link pins/holes, and tube hole/pump arm pin. Will keep wear on these parts to an absolute minimum. Almost like new. I've been thru a few tubes and pump arms on mine. Before using this lube. Though compression is higher on mine, the flat piston is enough to accelerate wear.
 
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Best bit of advice I can give you. Order a small bottle of Mac 1 secret sauce. Basically industrial hydraulic fluid. Use it on the pin for the piston, pump arm link pins/holes, and tube hole/pump arm pin. Will keep wear on these parts to an absolute minimum. Almost like new. I've been thru a few tubes and pump arms on mine. Before using this lube. Though compression is higher on mine, the flat piston is enough to accelerate wear.
Good advice...except I have a contact allergy to petroleum based lubes and solvents. I use silicone oil frequently on most things so I don't have to wear gloves while shooting. The years I spent working on cars were hell enough for me already.
 
Assuming you have some mechanical skills. And some basic tools the potential for these guns without spending too much is pretty great.
Trigger stop mod...about .35 cents
Other trigger components used...less than $5
Hammer spring adjuster...about .75-$1
Valve port mod....free vs $25 on ebay to buy 1.
Flow through bolt, neat but zero performance advantage you could skip that.
Angled valve port....free
Reduced valve volume....less than $1
1/2-20 barrel band....$25
Steel breech....$45
Optics/silencer....totally up to you
There are a lot of cool spendy parts available to bolt if you just wanna throw $$ at it....but you don't have to to get a good performing gun.
 
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My carbine stock is almost done 3d printing! I have been shooting this a bit and was having a real hard time believing my db rating on the finished product. So quiet I have had to 2nd guess myself a number of times about the power output. I took a new reading this morning that confirms my suspicions. I may have failed to reset the meter last night. Showing consistent readings indoors, at less than 2 ft away.
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while sending some superHpoints with force
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Obviously you're good with your hands. You should try making your own sear.
Piece of steel, 3/32 to 1/8 thick. You will need a drill press to drill and tap the #2-56 adjustment screw
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Have to remove the safety, ball & spring, and grind the plastic wall that retains the spring.
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A couple of 1/8" pins in a piece of scrap wood for a jig. That way you can see where you need to file.
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I don't have a trigger gauge but I'll tell you it makes your trigger really light and adjustable
 
Obviously you're good with your hands. You should try making your own sear.
Piece of steel, 3/32 to 1/8 thick. You will need a drill press to drill and tap the #2-56 adjustment screw
View attachment 458928
Have to remove the safety, ball & spring, and grind the plastic wall that retains the spring.
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A couple of 1/8" pins in a piece of scrap wood for a jig. That way you can see where you need to file.
View attachment 458932
I don't have a trigger gauge but I'll tell you it makes your trigger really light and adjustable
Looks like a fun project! I was hoping some other diy guys would pop up with some new mods to try, thank you. At the moment I have another thing to take care of on this. I think my original after mod sound reading may have picked up the pump slap when I closed the arm. Got an idea on how to make that closing of the arm much quieter, just have to dig through my supplies to see if I have what I need on hand.
 
I used some adhesive backed felt. Picked a 8 x 11 sheet for a buck. Works good.
I was looking around, I had some push on auto trim...but I can not locate it atm.
I did have a go at making a sear. Easy enough but my smallest tap is 4-32 and the tolerances are way too tight to make that work.
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tried some different ideas from yours reguarding shape, looks like it is possible to add the adjuster screw at a slight angle and not grind in the safety area.
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The ones I made are a lot longer and require you remove the safety. That way I get a lot of mechanical advantage.
I should open a gun up and post a pic of the sear in place. It's as close to the trigger pivot as possible.
A pic would be good. I see lengthening the sear as effectively shortening the "lever" on the trigger. Which would not add a lot of advantage
 
A pic would be good. I see lengthening the sear as effectively shortening the "lever" on the trigger. Which would not add a lot of advantage
I'll get a pic today and post it here.

I was going to wait till I get all my parts rounded up to build my "garage gun". But it will be a couple weeks before the flat top piston arrives. Monday till the air stripper material gets here. Got the barrel finished up yesterday, but still have to put a second screw in the breech.

Look like this one is going to be pieced together as I go. Would love to find an economical wood forearm and butt stock.
 
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Okay, this shows my sear installed on the gun. That little circular area on the trigger doesn't even contact the sear at all. That the wooden pointer / toothpick shows the area on the plastic side cover I had to remove for clearance. The seer actually covers the hole for the safety.View attachment 459245
Interesting...definitely an area I am gonna do some more experimenting.
A couple posts up I had mentioned that the Optics and silencer costs were up to whatever someone wants to put on there....well. this is the cheap way. 1 effective moderator I built from a lawnmower muffler, some delrin stock, and a couple grub screw....maybe $ 15
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