Air Venturi .22 hammer spring w/n adjust

[kernel32]

I have an AV Avenger .22, with the reg set between 1400-1900 psi there is little no difference in FPS when adjusting the hammer from full out to full in, aprx 5.5 turns in/out. The previous avenger I had set at 1400 psi on the reg and 3/4 hammer to achieve a velocity of 790-815 using 14.3g pellets. With this rifle no matter the hammer preload nor the reg setting from 1400-1900 I have velocities from high 870-915 consistently with no real difference on the chrony.  There are no leaks nor reg creep.  I did have some air blowing out the shroud/block end so I replaced two O-rings on the barrel past the xfer port and that leak is gone. Shot count is about 90. I can see differences in shot count, spread, deviation (all within the 870-915 range) when adjusting the hammer spring so a little change is happening. Any help would be greatly appreciated.

Thanks,
Charles

[TorqueMaster]

I have a .177 avenger that came with an obscenely high regulator setting, and a hammer spring that was way too much for it.
My point is, they may have installed a hotter spring at the factory than intended would be my best guess.  I found a couple types of springs at local Ace hardware to detune mine to suitable 177 power levels, they might work for a 22 as well.   Other option is start clipping coils off your stock spring, but I'm not a big fan of that -- no going back at that point -- I'd rather experiment on a test spring. 

[kernel32]

Thanks TM. That was pretty much what I was thinking. I'll try AH and see if I can find something that will work. Thanks for the reply.

-CH

[kernel32]

I have a .177 avenger that came with an obscenely high regulator setting, and a hammer spring that was way too much for it.
My point is, they may have installed a hotter spring at the factory than intended would be my best guess.  I found a couple types of springs at local Ace hardware to detune mine to suitable 177 power levels, they might work for a 22 as well.   Other option is start clipping coils off your stock spring, but I'm not a big fan of that -- no going back at that point -- I'd rather experiment on a test spring.

Just an update.
 I ended up cutting 1.5 coils out of the spring and then polished it. I also cleaned out the hammer adjustment, lots of thread/metal shavings, re-crimped the retaining wire on the adjustment screw. So now there is about 6 1/4 turns for the screw without the "soft stop" at turn 3ish.

 At 1400 psi, the range on the hammer is now fps 750-854 min to max turns. Currently avg fps is 804, hole in hole at 30 yrds. Another plus is I can get back to a reasonably close performance when I mess with the pressure/hammer and then return to the previous set point(s).
 
10 shots
spread 17
dev 4.9

107 shots from a 4000 psi fill.


Thanks again for the suggestion, TM.

-Charles

[TorqueMaster]

Excellent, glad to hear it's got some adjustability now. I forgot about that hammer adjustment hangup -- common problem.  Both my 177 Avenger ( iirc ~850 fps with 8.44 grainers) and 22 are lights out precise -- and the 177 seems to shoot all day before needing refilled. 

[Fred Jam37]

I'm having the same problem with my Avenge X in 25 Cal.  Hammer only can turn CW 3 turns in.  Everyone else has said they turn in 6 to 8 turns CW.  What could be wrong or should I just replace the Hammer Kit?

[kernel32]

I'm having the same problem with my Avenge X in 25 Cal.  Hammer only can turn CW 3 turns in.  Everyone else has said they turn in 6 to 8 turns CW.  What could be wrong or should I just replace the Hammer Kit?

Well, I am not sure how close the AvengerX is to the Avenger. I would suspect that the issue is probably the same. The threads on the hammer adjustment were fouled with metal shavings and alot of grease. Additionally, there is a retaining spring (more like a wire wrapped around the threads of the adjuster) at the end that keeps the adjuster from being turned in to far. I re-crimped that spring, keeping it in the grove, and sanded/polished both ends of it. I linked a vid that has all the variants of the AVx so it may help in removing the hammer adjuster.

I cannot post links, but a youtube search for, "Air Venturi Avenge-X Complete Servicing Guide - All Variants ..." should get you to the right place to disassemble.

Regards,
CH