Crosman 1377 Chrony data

[Smaug]

This has the melonair flat top piston kit in it. Supposed to be more powerful, and I recall that it was. But now, I'm not so sure. I put pellgunoil on the pumping O-ring and breech seal prior to shooting these.

Predator Polymag (8)
Avg 567
ES 3
SD 1
FPE 5.7

JSB Exact RS (7.3)
A 592
ES 12
SD 4
FPE 5.7

CPL (7.9)
A 575
ES 12
SD 4
FPE 5.8

RWS Basic (7)
A 600
ES 9
SD 4
FPE 5.6

AA Diabolo Express (7.9)
A 578
ES 7
SD 2
FPE 5.9


Conclusion: While I'm proud that I modded this myself, I can't say it was worth the effort. It is still quite a wimpy pistol, and the pumping still gets old FAST. (especially so, now that it's a little harder to pump)

 

[iride]

How many times did you pump it for each shot?
Mike

 

[Bobbed06]

My buddy brought his 1377 over to my place to target shoot with me. He seemed to think it was the cats meow before he had a chance to shoot my Ruger Blackhawk Elite 177 with a few mods. His 1377 had pellets bouncing off the plywood I used to dial in my scopes on at 15 yards. To be fair, his was probably a sick puppy, with no love given ever....

 

[ajshoots]

I had a 1322 that I built up and it never made alot of power unless I pumped it 15-20 times.

 

[bill_dd97]

Sure you didn't lose the adjustment on the piston? Those flat tops have to bottom out or they don't work right.

 

[Smaug]

10 pumps. I'm pretty sure the adjustments were right. 

I have a 24" barrel for it that I haven't tried yet, but I don't really want it to be a rifle, so I'll probably just leave 'er as a low power gun. 

 

[bill_dd97]

Your posted numbers look to be stock performance at just under 6fpe. Flat tops are for power (more pumps), they are an efficiency increase when installed properly due to the 0 spacing between piston and valve face when closed.