Valve Spring
What valve spring do folks have in their Talon SS? Wire thickness, length, number of coils?
I am rebuilding a used one and threw the spring in from my co2 adapter. When I pump up past 2200 psi, I get super low velocities – 540fps @ 2500 psi and power wheel max. I have the high flow valve from the co2 adapter in and the top hat at .126 in.. I am thinking a much lighter spring would work better due to the high pressure. The co2 must be stronger for the 800 psi of co2.. As my pressure drops past 2000, I get tons of air flow.
Thanks!
Dan
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I might disagree as the spring / nut combination is what really makes the difference.
Review this thread:
http://talonairgun.com/forum/viewtopic.php?t=21183&highlight=tagdagger
OK after much, much testing and experimenting. I reasoned out that the valve spring have very little if any impact on speed or response to pressure in the tank. The initial air pressure applies over 100 lbs of force on the valve seat, so an 8 lb spring is pretty negligible. I did pickup several sets of springs to experiment with. Changing valve springs is no fun with a hand pump – 8 or 9 sets of 50 double pumps to get back to 2000 psi.
Anyway, I learned that my existing hammer and hammer spring combo could not open the valve sufficiently, once the pressure was above 2100 psi. I called it “vapor lock”. I tried a heavier brass hammer, but I did not like the looks of it and it did not have a guide to reduce friction on the frame and reduce impact on the breech. So I picked up several sets of hammer springs. The first one I tried (.072 diameter stainless) gave wonderful results with the stock hammer and follower (87 grams total): 940 fps with 14.6gr CHP for about 28 fpe, and 833 fps with 21 gr Kodiak for 32 fpe (top hat at .1 – though changed through the test, and PW=7). Air usage was 18.5 psi per shot and I shot over 40 times with less than a 10% drop from peak speed. I think I am at my peak optimization for this 12″ barrel and a 2100 psi fill.
I tried one additional, heavier spring and it was a bit higher, but the first one was too good and I dropped back to it.
I would be curious if the above results match other folk’s experiences with the Talon SS with the 12″ barrel
Dan
What Mrnewbie said.
Its not unusual to not open the valve all the way for a tallonss.
Try shooting at 2200psi, or add a hammer weight.
But I would rather shoot a pellet at 900fps only using 2000 psi rather than 2800psi
.126 is a lot of tophat…standard settings are .90 to .100., many run them at .70’s. or even less.
lower tophat..fill to 2200-2300, try it, then if you can’t reach your desired fps, add the hammer weight.
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( I reasoned out that the valve spring have very little if any impact on speed or response to pressure in the tank )
Thats because you only have a 12″ barrel….
The valve spring changes would have a much larger effect on a longer barrel, but with a 12″ barrel, heck the pellets already out of the barrel and your just waisting air.