New Seneca Dragonfly?

[Nvreloader]

OK Guys
Here is the  full 15 shot+ pumps test, 3 pumps per the number,
with the OEM 18/19# spring, full length.

The average is this, 14 gr Crosman ammo.
1 pump = 265 fps
2 pumps= 288 fps
3 pumps= 322 fps
4 pumps= 465 fps
5 pumps= 515 fps
6 pumps= 567 fps
7 pumps = 600 fps
8 pumps = 633 fps
9 pumps = 652 fps
10 pumps = 666 fps
11 pumps = 678 fps
12 pumps = 679 fps
13 pumps = 681 fps
14 pumps = 680 fps
15 pumps = 679 fps
16 thru 20 pumps = 679 to 688 fps, (1 pump test only for these last shots)
there was no extra air left after the shot.

NO MORE, I am pooped,

IMHO, 10 to 12 pumps will be MY maximum effort,
for the little gain above this is not worth the effort.     YMMV

Here is one thing I cannot wrap my head around,..........
If you don't cock the bolt, and complete a full pump stroke,
you can hear the pumped air escape etc.

How can this be happening, there is no valve to release this pumped air,

The only thing I can think of, the valve poppet releases the air,
because of the hammer resting on the end of the valve stem,
and is not allowing the valve to retain this air??

Your thoughts and suggestions...............
Tia,
Don

[Back_Roads]

On my stock DF2 I found 12 pumps to be the most consistent for high power shots, My 2¢

[Psipumper]

OK Guys
Here is the  full 15 shot+ pumps test, 3 pumps per the number,
with the 11# Flat wire spring, full length.

The average is this, 14 gr Crosman ammo.
1 pump = 265 fps
2 pumps= 288 fps
3 pumps= 322 fps
4 pumps= 465 fps
5 pumps= 515 fps
6 pumps= 567 fps
7 pumps = 600 fps
8 pumps = 633 fps
9 pumps = 652 fps
10 pumps = 666 fps
11 pumps = 678 fps
12 pumps = 679 fps
13 pumps = 681 fps
14 pumps = 680 fps
15 pumps = 679 fps
16 thru 20 pumps = 679 to 688 fps, (1 pump test only for these last shots)
there was no extra air left after the shot.

NO MORE, I am pooped,

IMHO, 10 to 12 pumps will be MY maximum effort,
for the little gain above this is not worth the effort.     YMMV

Here is one thing I cannot wrap my head around,..........
If you don't cock the bolt, and complete a full pump stroke,
you can hear the pumped air escape etc.

How can this be happening, there is no valve to release this pumped air,

The only thing I can think of, the valve poppet releases the air,
because of the hammer resting on the end of the valve stem,
and is not allowing the valve to retain this air??

Your thoughts and suggestions...............
Tia,
Don

If you hear the air leaking out from the end of the barrel, it would be leaking past the poppet due to low pressure to seal on only one pump.
Looking at your numbers peaking at around nine or ten and not gaining much more maybe the pump pressure is not above what is already in the valve so no more pressure can go into it. Must be some extra headspace in there.
I don’t know what to expect from the df2 in power or the durability of the pump linkage. My guess would be about 19 fpe would make a long lasting gun. Wouldn’t hurt to collect a spare pump linkage.

[Nvreloader]

Hi Charles
How can I chrono 1 shot, if the air is leaking past the poppet due to low pressure?

IMHO, it has to be that the hammer is pushing hard enough on the poppet stem,
allowing the air to leak past the poppet.

When the rifle is cocked, the poppet seals and holds the air..........
allowing the pumped air to build pressure etc.

I'll do a test and remove the hammer spring and see if the valve passes the pumper air,
or holds the air, when the bolt is NOT cocked etc.

There is approximately 1" of extra headspace between the end of the pump rod head
and the face of the valve, as I posted  earlier.  As soon as I am finished with testing session,
I'll dive into this extra headspace issue and see what can happen to use this headspace up.

I still have to do the Flat Wire 11# spring and the 15 pump test also.

Your thoughts and suggestions...............
Tia,
Don

If you hear the air leaking out from the end of the barrel, it would be leaking past the poppet due to low pressure to seal on only one pump.
Looking at your numbers peaking at around nine or ten and not gaining much more maybe the pump pressure is not above what is already in the valve so no more pressure can go into it. Must be some extra headspace in there.
I don’t know what to expect from the df2 in power or the durability of the pump linkage. My guess would be about 19 fpe would make a long lasting gun. Wouldn’t hurt to collect a spare pump linkage. [/quote]

[19Sheridan57]

   I haven't read all the posts, but I thought those had more power than that when stock.  Anything more than 9 pumps is negligible, in my opinion.

[Spacebus]

Cock the gun before you pump, like A Diasy 901/880.

[Nvreloader]

Hi Steve
From what I have been reading, apparently the OEM hammer spring is too strong?
I have been testing a Flat Wire 11# spring and gain a better amount of power,
along with very easy bolt pull pressure.
I finished the 15 shot pump test using the OEM 18/19# weight and the results
weren't that good in my humble opinion.

I'll change the OEM spring out to the 11# weight and retest the 15 pump test, to see the results.
Thanks,
Your thoughts and suggestions.....
Tia,
Don

   I haven't read all the posts, but I thought those had more power than that when stock.  Anything more than 9 pumps is negligible, in my opinion.

[Nvreloader]

DJ
Did you read the question I ask in post# 360?   

"Here is one thing I cannot wrap my head around,..........
If you don't cock the bolt, and complete a full pump stroke,
you can hear the pumped air escape etc.

How can this be happening, there is no valve to release this pumped air?"

The only thing I can think of, the valve poppet releases the air,
because of the hammer is resting on the end of the valve stem,
and is not allowing the valve to retain this air??

I know to cock the rifle before pumping..............

Your thoughts and suggestions...............
Tia,
Don

Cock the gun before you pump, like A Diasy 901/880.

[Nvreloader]

As an update to my question, 

I changed the hammer spring out to my 11# Flat Wire spring, for the pending 15 pump test,
and I found out the OEM hammer spring 18/19# does allow the hammer to rest
on and hold the valve stem open to release the pumped air, when the hammer is not cocked back.
This released air comes out the barrel.

Tia,
Don

[Nvreloader]

OK
Here is the  full 15 shot pump test, 3 pumps per the number,
with the 11# Flat wire spring, full length, with crosman ammo 14 gr.

The average is,
1 pump = 265 fps
2 pumps = 288 fps
3 pumps = 383 fps
4 pumps = 469 fps
5 pumps = 524 fps
6 pumps = 567 fps
7 pumps = 613 fps
8 pumps = 636 fps
9 pumps = 652 fps
10 pumps = 688 fps
11 thru 15 pumps = 688 fps or less, (1 pump test only for these last shots)
there was no extra air left after the shots.

I feel that the point of no return has been reached
between the valve/hammer spring -vs- pumps. 

I think, I need to lighten the valve spring just a touch,
as it is fairly heavy duty (not measured or tested yet,
and  or maybe add a slightly heavier hammer spring?

Your thoughts and suggestions........
Tia,
Don

[splitbeing]

As an update to my question, 

I changed the hammer spring out to my 11# Flat Wire spring, for the pending 15 pump test,
and I found out the OEM hammer spring 18/19# does allow the hammer to rest
on and hold the valve stem open to release the pumped air, when the hammer is not cocked back.
This released air comes out the barrel.

Tia,
Don

Thanks, Don! That is interesting!

[splitbeing]

OK
Here is the  full 15 shot pump test, 3 pumps per the number,
with the 11# Flat wire spring, full length, with crosman ammo 14 gr.

The average is,
1 pump = 265 fps
2 pumps = 288 fps
3 pumps = 383 fps
4 pumps = 469 fps
5 pumps = 524 fps
6 pumps = 567 fps
7 pumps = 613 fps
8 pumps = 636 fps
9 pumps = 652 fps
10 pumps = 688 fps
11 thru 15 pumps = 688 fps or less, (1 pump test only for these last shots)
there was no extra air left after the shots.

I feel that the point of no return has been reached
between the valve/hammer spring -vs- pumps. 

I think, I need to lighten the valve spring just a touch,
as it is fairly heavy duty (not measured or tested yet,
and  or maybe add a slightly heavier hammer spring?

Your thoughts and suggestions........
Tia,
Don

If the valve spring can be replaced with the non OEM spring you are using to make the custom hammer spring, making a custom valve spring and seeing what happens is the more interesting route to my mind, but my mind has never experienced making such changes to a pumper.  A lighter valve spring makes sense intuitively to balance the forces.  Thank you and keep us posted Don!

[Nvreloader]

SB
I think there is several factors going on,
1. There is about 1" of extra headspace between the pump head and valve face,
these ends should be fairly close without touching for the maximum pumping,
and maximum FPS effort.

2. The valve spring is fairly Heavy Duty, and with the pumped pressure contained
inside the valve, I believe that these combined pressures are all the pump can force
into the valve, maybe a lighter valve spring will allow more pumped pressure
to be retained.

3. The OEM hammer spring is way too heavy in power weight,
I know the 11# hammer spring works very well and has a lighter bolt pull force,
but may need to be adjusted after the above problems are corrected,
careful testing should provide road too travel.

I'll start with the valve spring and do a 15 pump test, both OEM Hammer spring and
my 11# Flat Wire spring, and then work on the extra headspace,
and may make a new valve to used up the extra headspace being wasted now
and see where that leads too. 

Thank you,
Your thoughts and suggestions..........
Don

[HOSPassassin]

SB
I think there is several factors going on,
1. There is about 1" of extra headspace between the pump head and valve face,
these ends should be fairly close without touching for the maximum pumping,
and maximum FPS effort.

2. The valve spring is fairly Heavy Duty, and with the pumped pressure contained
inside the valve, I believe that these combined pressures are all the pump can force
into the valve, maybe a lighter valve spring will allow more pumped pressure
to be retained.

3. The OEM hammer spring is way too heavy in power weight,
I know the 11# hammer spring works very well and has a lighter bolt pull force,
but may need to be adjusted after the above problems are corrected,
careful testing should provide road too travel.

I'll start with the valve spring and do a 15 pump test, both OEM Hammer spring and
my 11# Flat Wire spring, and then work on the extra headspace,
and may make a new valve to used up the extra headspace being wasted now
and see where that leads too. 

Thank you,
Your thoughts and suggestions..........
Don

I think yours definitely has a gremlin in it somewhere. Mine seems to build more pressure more quickly and level off sooner. Three pumps is 450-ish and five pumps gives me about 550 fps with the same ammo. I don't think it goes much higher if at all at the top, though.

[Nvreloader]

Hosp
LOL  That's why it was listed as "REFURB", when I first got it I could hardy pump it,
lubed all the correct points etc, and it stated acting like a normal pumper......, like me..........
stiff, hard to move, "The get up and go, Got up and left" and after a couple of warm up tries,
"Hey, I can move"...........LOL 
This pumper has ALLWAYS been ODD.   
I bought it thinking as a parts gun, for when I got a new good one, learn on this one etc.

But I have grown to KINDA LIKE HER< so I'll see how far she leads me down the Garden Path
and watching for her little surprizes she may throw at me, then I'll be singing "Help Me Ronda,
Help, Help me..........LOL.

Comparing the pump tests I have done so far, she seems a little twisted,
Chrono test (OEM STOCK RIFLE) on my new Dragon Fly II (Refub),
with these results, with my Chinese chrono, same ammo used thru out these tests.
1. Chrono test = 14 gr Crosman HP
5 shot group at 5 pumps averaged 546 fps,
5 shot group at 10 pumps averaged 640 fps.

2. Chrono Test
5 shot group at 5 pumps averaged 556 fps,
5 shot group at 10 pumps averaged 668 fps.

Chrono test was with the hammer spring tunnel opened to .420",
and with a 11# Flat wire spring, 5" long,
3. Chrono test
5 shot group at 5 pumps averaged 631 fps,
5 shot group at 10 pumps averaged 684fps.

Chrono test #4 was with the spring tunnel opened to .420",
and with a 18/19# OEM SPRING, same ammo as used before.,
(OEM Hammer spring is 18/19#'s at max compression, (coil bound), 3.150" long,
.390" dia  O/S dim, x  .300" I/S dim, with 15 coils.)

#4. Chrono test
5 shot group at 5 pumps averaged 552 fps,
5 shot group at 10 pumps averaged 645 fps.
This chrono test is with the pump head lengthened 1 full turn from the OEM setting,

I just finished the 1 >10 pumps x 3 each per pump,
pumps were a complete cycle, open then closed arm pump arm, per each pump stroke.
1 complete turn on pump rod, nothing else changed. A 11# Flat wire spring, 5" long,
.415" O/S Dia, .252" I/S dia, 35 coils, .023" thick Flat wire, coil bound at less than 1.030"
1 pump = 288 fps
2 pumps= 321 fps
3 pumps= 354 fps
4 pumps= 561 fps
5 pumps= 597fps
6 pumps= 610fps
7 pumps =616fps
8 pumps =620fps
9 pumps =656fps
10 pumps =688fps
No remaining air in pressure tube for any shot.

Here is the  full 15 shot+ pumps test, 3 pumps per the number,
with the OEM 18/19# spring, full length, same as above.
1 pump = 265 fps
2 pumps= 288 fps
3 pumps= 322 fps
4 pumps= 465 fps
5 pumps= 515 fps
6 pumps= 567 fps
7 pumps = 600 fps
8 pumps = 633 fps
9 pumps = 652 fps
10 pumps = 666 fps
11 pumps = 678 fps
12 pumps = 679 fps
13 pumps = 681 fps
14 pumps = 680 fps
15 pumps = 679 fps
16 thru 20 pumps = 679 to 688 fps, (1 pump test only for these last shots)
there was no extra air left after the shot.

15 shot pump test, 3 pumps per the number,
with the 11# Flat wire spring, full length, same as above.
1 pump = 265 fps
2 pumps = 288 fps
3 pumps = 383 fps
4 pumps = 469 fps
5 pumps = 524 fps
6 pumps = 567 fps
7 pumps = 613 fps
8 pumps = 636 fps
9 pumps = 652 fps
10 pumps = 688 fps
11 thru 15 pumps = 688 fps or less, (1 pump test only for these last shots)
there was no extra air left after the shots.

My next step will be the valve main spring,
I think it is limiting the power/fps available, by being overly too strong (IMHO).

Thank you,
Your thoughts and suggestions..............
Tia,
Don

[HOSPassassin]

IIRC Wes at AirgunsArcheryFun figured out how to mod the Dragonfly for  LOT more power mainly by installing a weaker hammer spring. It sounds counterintuitive but it was said by a lot of reputable people to work to the tune of almost doubling muzzle energy. Is that where you're eventually headed?

Where I live a 50 yard shot on a squirrel is pretty long so I don't care that much about more power. I'm happy with mine the way it is. 12.3 ft-lbs after 8 pumps will get me out to 30 yards easily and 40 if everything comes together just right.

[splitbeing]

After the valve spring change, transfer port... but that's thinking steps ahead! Valve spring could do lots or nothing! Excited to read results!

[Nvreloader]

Hosp
Yes,
Attempting to give a good overall picture of this rifle and possible improvements/potential,
if the owners want to go there, I am tickled pick with the results so far,
but I feel there is a lot left on the table, that is not being used..

I am just taking the long way around and making sure I cover most of the bases.
Wes, does use a weaker hammer spring and opens the air ways up,
for his great success in the 25 cal DF II rifles.

Just compare/take a look at the OEM (18/19#spring) -vs- 11# FW spring I use,
and I haven't open any air ways yet.

I'll have to make a slightly thinner diameter spring test rod
so I can measure the OEM valve spring etc,
then I'll try a lighter spring rate for the valve spring and do some tests.
Your thoughts and suggestions,
Tia,
Don

IIRC Wes at AirgunsArcheryFun figured out how to mod the Dragonfly for  LOT more power mainly by installing a weaker hammer spring. It sounds counterintuitive but it was said by a lot of reputable people to work to the tune of almost doubling muzzle energy. Is that where you're eventually headed?

[Nvreloader]

Thanks Sb
I am going to find out...........LOL   

Tia,
Don

[Nvreloader]

Here is the next installment of information.
Stripped her down to  small parts and did some careful measurements.

Using the maximum measurements on how deep the the pump rod head goes
into the pressure tube and the length of the valve when when seated
on the pressure tube crimp marks, there is .610" of dead headspace right now.

So, I moved the pump rod head out (longer) by 1 turn,
I am at the maximum length (2 full turns) possible and still allow air to be drawn
in thru the pressure tube air vent.
The only way to use this dead pump rod headspace air is to make a .600" longer valve head.

Valve info:
Pressure tube = .870" O/S and .770" I/S diameter,
Valve length overall = 2.520"
O/S diameter = . 765" 
Air inlet hole = .100" Dia by .180" long, with that compressed type of air screen at the end,
then taper into the valve main chamber = .450" diameter by 2.170" long,
(contains the valve spring and plastic seats).
 
Both ends of this air chamber are tapered, the inlet side has the tapered plastic seat/seals,
(for containment of pumped air) and the exit end also has a taper for the valve seat/seals.

Valve spring =1.475" long by .295" O/S dia, 12 coils, spring weight of 3.5#'s,

Valve sealing "O" ring = .070" thick x .550" I/S dia x .690" O/S dia, (Middle "o" ring)
Valve sealing "O" rings for pressure tube = .113" thick x .520" I/S dia x .745" O/S diam,
x 2 "O" rings.

TP "O" rings .078" thick x .231" I/S dia x .395" O/S dia. x 2 "o" rings,
1 in valve and 1 in the action.

BBL "O" ring = .056" thick x .215" I/S dia x .326" O/S dia. for end of the bbl,
for bolt sealing.

There is a very distinct hammer impact of the rear of the valve,
valve stem length protrusion of .110" at the end of the valve,
I'll be using a SSG to reduce this contact...........

I'll do a 10 pump test to see any changes.

Your thoughts and suggestions.....
Tia,
Don