Originally Posted by Tempted
I've almost got it timed. This is the first time I've ever tried to time a Cocker.
Here's what I like to do:
First, set the back block (screw it further on/off the pump arm). It should be as close to the body as possible without touching it.
Next, set the cocking rod. Pull back the back block untill the sear engages. Look down the feed tube. You should see a sliver of the front of the bolt (about 1/8"). If you see too much bolt, lengthen the rod. Too little, make the rod shorter. To change the 'length' of the cocking rod loosen the set screw that holds the end knob in place. Adjust the knob and re-tighten the set screw.
Then comes the 'timing'. To conserve air, make sure the hammer is not engaged and remove the cocking rod. Now, when you air up the marker you will have pressure to test the 3-way, adjust the actuation point and make sure there are no leaks. Depending on whether your frame has a front stop or rear stop, adjust the actuation point toward the unadjustable part of your pull. Then later, you can remove the excess pull by adjusting your trigger stop.
After you get the 3-way squared away you will need to replace the cocking rod and adjust your lug so the hammer releases just ahead of your actuation point. To test; pull the trigger very slowly. You should be able to release the hammer with the back block still fully forward. Any additional pull should actuate the 3-way (moving the block back).
If you can't release the hammer with the block forward, you need to either raise the lug or adjust the 3-way to actuate further back. BTW, I like to time my mechs very close. I have to be able to pass the release test, but it can't be overly easy to do.