1377-- 40 Pumps, All Air Dumped

[woody67]

I posted this link in a different thread, but here it is all on it's own.


[youtube]https://www.youtube.com/watch?v=67TQvXjVvC0#]1377 FT Piston/Valve, 40 Pumps, All Air Dumped[/url]

[quickster47 †]

My only question is why would you ever want to pump your gun 40 times?  Have you checked to see what kind of FPS increase you are getting from say 10 to 20 to 30 to 40 pumps?

Carl

[1377x]

as heavy of a spring you are using i can believe it
when pumping that much
how do you do it?
slow,fast ,pausing in between sets
any noticed differences between 30 and 40 pumps?

[quickster47 †]

From watching the video looks like it was just 40 continuous pumps with perhaps a pause somewhere.   Man, it made my biceps and triceps tired watching it. 

Carl

[arkmaker †]

Dang! You need to Chrony that bad boy!!

[1377x]

questions answered by watching the video
it must have been a nice and warm after all the pumping
i found in my gun after 25 pumps no worth while gain was found
since you are pumping 40x try some heavier pellets like 18gr -21gr

[quickster47 †]

questions answered by watching the video
it must have been a nice and warm after all the pumping
i found in my gun after 25 pumps no worth while gain was found
since you are pumping 40x try some heavier pellets like 18gr -21gr

I think his gun is a .177 caliber and it's going to be difficult to find some really heavy pellets.  Best I've come across is the Skenco NewBoy Senior pellets weighing 15.8 grains.

Unless, of course, he has changed it over to .22 caliber.

Carl

[Bentong]

EUNJIN come in 16.1 grains @ .177
When I hit 828.7 fps with 7.9 cpl 20 pumps, I quit getting any higher...too much work. I dispatch nutter to 30 yrds with 10 pumps yielding 709fps with .177 predators.

[1377x]

16gr is more ideal
i have shot 21gr kodiaks 600+fps out of a modded 1377
now that i think about it it wasnt worth the effort and a waste of kodiaks at the time.beeman quit making them h&n did start putting them out yet(at that time)
now 16gr pellets they did a great job out to 25-30 yards

[woody67]

This is a .22 cal with a 14" barrel

I don't ever pump to 40, I just found that I could while I was testing it the other day.

Before I changed the valve spring and added that small piece behind the stock hammer spring the valve was holding air after firing after about 13 or 15 pumps.
I wanted to dump all air at 20 pumps--thus the spring manipulating. It worked, so I tried 30 to see if it held air after the 1st shot--it didn't. After I while I grew curious and decided to try 40. Still dumped it all.          I'm wondering when I'll have the urge to try 50.

I don't have a need to pump to 40. I normally pump 6 or 8 times, sometimes 10. I want it to be able to do 20 in case I decide to hunt with it.
I just made the video to show that it is actually dumping all air at 40. Maybe this spring setup could be good in that 1377 with the monster valve? I don't remember who made it, but it was on this forum a while back......

Wish I had a chronograph. Anyone on here live in South Florida and have one?

[1377x]

ahhh come on,man
we all need to pump our 13XX's up to 50x
just kidding
i dont think you really need to go more than 20 if using a 16gr pellet
for pesting i would use a jsb stratton 16gr and pump 12x.my nephew would pump 20-25x
the end result was still the same dead nutter
i found during testing the stratton has superior penetration/expansion over cphp and rws super pointed pellets

[quickster47 †]

The Predator Polymag .22 Cal, 16.0 grain pellets are my choice for hunting.  Maybe a tad expensive but I guarantee they do the job and do it excellently.

Carl

[1377x]

i see those pellets everytime i go to the shop
cant get past the price!
i see pics of the devestation they do if i was hunting instead of pesting,i would splurge in a heart beat!

[quickster47 †]

i see those pellets everytime i go to the shop
cant get past the price!
i see pics of the devestation they do if i was hunting instead of pesting,i would splurge in a heart beat!

I'll splurge and send you a tin in .22 for Christmas. 

Carl

[Cross Pistol Packer]

Have pumped my 1389 (same valve as 1377) up to 20x
but found the gain from 15 pumps to 20 not worth the extra effort,and yes all air was dumped thanks to pre load on hammer spring.
Point of interest here,AC brass FTP 11.2ftlbs at 15 pumps
Gmacs Delrin FTP 20 pumps for same power,my thinking here is that Gmac o-ring sits a little further back from piston face so less air compression per pump.
Both real good flat top pistons,Oh and my barrel length is 19inches and my valve one of ACs souped up jobs