I think I solved my hand pumping problem...

[splitbeing]

... I got two avengers. The exercise journey of keeping these guns at full pressure for tuning begins. Problem of pumping being easy: solved? Time will tell.

Gonna try a low power tune on the .25 and a high power tune on .177.

One of them came with the front pic rail screw missing, which appears to connect it to the wood stock and so is important.

Anyone know the hammer spring measurements for the various calibers? Or if true value or hardware stores carry comparable sizes for custom spring making?

Thanks all!

[TorqueMaster]

Check out this thread for a bit of spring info.

https://www.gatewaytoairguns.org/GTA/index.php?topic=197391.msg156300887#msg156300887

I think there was another thread similar in nature, also by Dairyboy.

From my notes, pretty sure the factory spring is  "2.4" long, 0.056" wire, 0.354" od, 0.237" id"
I used Ace Hardware spring rather than cutting up the original in my .177 Avenger.  I am convinced the factory installed spring was for a .22 -- adjuster had no effect on velocity unless pressure was set over 2150, and most pellets were going supersonic iirc.  Might be fine for you if using heavy ammo.

My notes say I was cutting down this one:   Ace Servalite #44 (3.25" x 5/16 od 0.047" wire) with a K factor approximately 75% of the original.

[splitbeing]

Thanks Bob! Exactly what I was looking for!

I swapped the .177 hammer spring with the .25 spring.

[TorqueMaster]

Glad to help.
I'm curious if the .177 or .25 springs you found were different from the presumed ".22" spring I found in my .177?

[splitbeing]

Glad to help.
I'm curious if the .177 or .25 springs you found were different from the presumed ".22" spring I found in my .177?

On the left is a spring I got (and already cut a piece off of) from my local, little hardware store for $3. On the left is the .25 spring that I replaced with a lighter one (the hardware store spring is lighter by a bit so I kept about the same length).

The ..25 stock spring is the same as the .177 stock spring, just a couple centimeters longer. PA told me the vavles and parts generally are the same across models except for the hammer springs.

[splitbeing]

Server won't let me upload a picture like it used to.  Sorry. Will try again later.

[splitbeing]

Here's the pic