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Crosman 1322 1377 mod questions

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Raden1942

Raden1942

Member
Feb 15, 2018
1,757
74
California, United States
 Ok so I have a 1322 I want to mod to the max. I already have alliance hobby flat man pack which come with all the power mods minus the adjuster. I want to use it yo kill rabbit under 50 yards. I also want to keep the barrel 18inches or under. So I am wondering a couple of things. A 1300kt from the custom shop has a 14.5in lothar walther barrel and a steel breech for like 140 after agnation discount but thats in 177. I dont know if the gun with power mods can kill a rabbit ethically at 50 yards. Could someone who has done these power mods on a 14.5in 177 barrel please let me know the chrony numbers your getting? Also the cost of modding my pistol to longer barrel is about the same as buying the 1300kt and I am not sure if its worth it to even mod mine or if i should buy a 1300kt and start over. Also does anyone know of a source for lothar walther 22cal barrels that are 18in. This is my original desired length and caliber but the 14.5in 177 seems like too good of a deal. Thanks guys you have been helping me alot these days. I always have new projects and your ideas are so important to me.
 
You need more than just higher pressure in the valve. You need more volume. If you open the valve, cut 3-4 of the male threads off. Long before this website, there was a site all in yellow. This mod was second on the list after flat top/piston valve. Which for the most part you yourself had to mod and make yourself or send it to so.some. All of whom are probably hanging out with worms six feet under

The volume of a stock crosman valve is less than the volume of a .22 barrel @ 14.5. I believe it is equal at 12 and greater by 10% in a 10" barrel. It is easier to get a 177 to performer better, the lower volume of the caliber barrel in relation the volume in the valve. I believe crosman figured that out with the 2289 came with a 12" barrel and a quick release for the 1389stock

Let's say your barrel has a volume of 12 cu inches and your valve has 10cu inches. 
 
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Flat top valve, piston, and Boss TP installed..... Velocity went up ever so slightly (getting 550 fps now with 16 pumps) but for some reason I can only get about 20 shots before accuracy goes to hell and I have to clean the barrel.

There must be a bunch of oil in the valve. Hopefully it will clear out fairly soon.

Interesting thing is that my valve retains air at any more than 16 pumps, so I may need a heavier hammer spring. The stock valve would dump 18 pumps (???)

I swear, there's no end to this poop !
 
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