Flat top piston and valve???

[mcc1961]

I have a FT piston and valve coming today that I got from Mr. Mellon and was wanting to know what is the max pumps I can do with it?

[1377x]

with a stock hammer spring 14 then the valve will retain air

[1377x]

oops forgot to add
if you get mellons power adjuster i have never tried one up to 20 pumps
if you go with a disco hammer spring iirc 25 pumps any more than that doesnt get the numbers any higher.
someone might say it is harder to cock the gun imo its about the same
if you already cocked a disco then you know already

[woody67]

Melon's valve is a monster. It will hold over 40 pumps and fire (with the right setup of springs) without a problem.
1377X is right though, with stock spring set up the valve will retain air after @14 pumps.



If you're the one who's trying to put it in your 2240, You can pump it up as many times as you want. Haha

[1377x]

i have a .041 stainless steel spring wire that can dump 60 pumps
the gain between 35-60 pumps is not worth it
at 35 pumps i can launch a 21g kodiak at 662fps thats 20fpe out of a 2289g
pumping past 35x might get me 12fps more
not to mention you need a cheater bar to cock it
the disco spring gets me to 12fpe in 15 pumps.i dont need any more than that
i see the UK guys taking small game at 40yds sub 12fpe.if they can do it so can i. the gun is accurate enough, it is then left up to the shooter

[AZAG]

Will heavier pellets cause the valve to retain air at a lower number of pumps?  I have a FT piston and valve in my 22 cal carbine and it retains air at 10 pumps with 14.5 gn pellets.

[1377x]

Will heavier pellets cause the valve to retain air at a lower number of pumps?  I have a FT piston and valve in my 22 cal carbine and it retains air at 10 pumps with 14.5 gn pellets.

the first thing that comes to mind is your hammer spring is weak
where did the valve come from

[AZAG]

Its a Mellon Air Piston and Valve.

[1377x]

Its a Mellon Air Piston and Valve.

my first guess would be weak hammer spring
maybe sear drag
how old is the gun?

[AZAG]

my first guess would be weak hammer spring
maybe sear drag
how old is the gun?

I don't think that any of the individual pieces are very old.  All less that a year.  It started life as a reman 1377, and converted to 22cal carbine.  It has a power adjuster that I haven't played with, it may be in the "all the way out" position.

[1377x]

I don't think that any of the individual pieces are very old.  All less that a year.  It started life as a reman 1377, and converted to 22cal carbine.  It has a power adjuster that I haven't played with, it may be in the "all the way out" position.

i sent you a pm after seeing the gun in the gallery if its the one you are talking about
when i saw the adapter that was the next solution did you adjust the power adjuster?
try that and report back

[mcc1961]

I put the gun together today .I have a Disco hammer spring with power adjuster,Cothran trigger,TKO trigger kit,24" barrel, FT valve and piston  and muzzle brake.I also painted it with truck bed liner on the stock and pumparm.Here is the finished product.

[1377x]

wow!
thats one fine shooter you have there!!!
a disco hammer spring and power adjuster.how times are you planning on pumping
pellet holer in a good place
that rig is going to be one hard hitting shooter
i would like to see how a 18gr jsb pellet would register out it .heck even a 21gr pellet if you want to pump it 25x
it going to be quiet for sure
nice job!

[mcc1961]

It's only a .177 but what FPS do you think i get with 7.9 grain pellets.Just a guesstimate ,don't have a chrono.

[1377x]

It's only a .177 but what FPS do you think i get with 7.9 grain pellets.Just a guesstimate ,don't have a chrono.

i would say 700+ depending on how many pumps 10 or more.with your spring set up you could easily go to 25
if you do that many pump slow so the gun doesnt heat up
heck you coud go with a 10.5gr pellet with the parts you have