1377 re-mod

[Spooner]

now that i have the new 1377 done (its working great) and applied those tips and advice from members here to the 1322 which is also working great... i started the re-mod of my first 1377 this morning. i am very glad that i trust my instincts! i ordered a spare FT setup from Mellon Air and good thing i did  . the spacer (dont ask, lol) i was using on the drill bit deformed and i blew into the valve area. its ruined. oh well, the new valve drilling went fine and the valve pinning is done. i put the flat spots on the hammer at work last night, added shims to the pump arm to valve section, piston adjusted properly to the valve, and the shim spacer from Mellon to the pump arm end. i will do the deburring tonight. I am off for the next four days... should have it wrapped up this weekend. 

[mr007s]

good luck with your new build

[Spooner]

thanks Ray... it is partially assembled now. 

ok, so i have hit a snag and i am scratching my head on this one? when i set up the piston to the valve, it was 1/2" pretty much exactly from close with no pumps. i pumped it 10 times to check that when the handle is open, it is about 30 degrees. this is what i got...


after the ten pumps, this is where it now rests with no pumps, which is not where i set it...


i have tried going in on the piston but the result is the same. if i go in any further, the handle will not stay closed with no pumps, and opens too easily when it is pumped? i had to split the difference and find an adjustments that keeps it closed with or without pumps... the above pics is where it is.

this is a brand new FT piston and valve, but i also tried the piston from the original FT valve, same thing with both pistons? at 20 pumps, it does not retain air, so at least that part is right and i did the exact same things to this gun as i did my new one, and the 1322. for what ever reason... this one wants to be different. 

[Spooner]

its all back together and the chronies are in...
crosman LW 14.6" barrel, 7.4g super points at 10 pumps...
585 / 5.6
596 / 5.8
601 / 5.9
602 / 6.0
603 / 6.0
595 / 5.8
602 / 6.0
597 / 5.9

these are actually fairly respectable with the choked LW barrel. not nearly as good as my newest one with the exact same mods and corrections, but decent and better than it was before all of this. i cant understand how two identical guns with the same identical setup can be so different, or why this particular one will not adjust out correctly, but there is definitely too much headspace when pumped at 10 pumps and no reason as to why? either way, i have done all i can and was very careful to duplicate what i did on the new one, to this one. time to call a quits. i now have a 2400KT, this 1377, and a 1322 all to get sighted back in. the 1077 is ready, but on hold for now. my Dad gave me his vintage Ruger 10/22 and i also have that to sight in... gonna be a busy summer, lol. 

[Spooner]

so i decided to go outside my comfort zone with choosing a pellet for this one, and this one agreed. i went with a tin of JSB 10.34g Hades pellets that i had and this gun really likes them! even though i didnt get results as good as my newest build by re-modding this one, it is getting 1/2" groups at 25 yards with 6 pumps, and these pellets hit really hard! next time out with it, i will do some chrony readings.