Hammer Spring Mod

There are a number of ways to increase shot count in the 2240. One way to do this that requires a minimum of tools and trouble is to shorten the mainspring. As before when the power adjuster mod was discussed the receiver end cap needs to be removed.

Again it is best to remove one grip panel and use a 4 iinch shank #2 square drive on the rear frame screw. A 4 inch #2 flat blade will suffice but can damage the screw head. If you have used silicone adhesive to secure the panel you do not need to clean it away and reapply it, though it may be necessary to force the panel away from the frame.

You can see that this pistol has the clipped sear spring with support washer and the anti-cant washer under the front frame screw. Both of these have been discussed in earlier posts. For the increased shot count we simplyI clip off a 1/4 inch from the mainspring and it is not necessary to access the valve. When I cut 1/4 inch (3 coils counting the closed end as one coil) the results were remarkable.

There was a 78% increase in shot count and I got 25 more usable shots over the original 32 usable shots I was getting under the test conditions. Usable shots were those shots that did not fall below 400 fps.

Usually when increasing shot count we find that the velocity decreases. In this case the average velocity decreased from 431fps to 413fps (4.2%). What was most notable was that the standard deviation of the shot string was 5 and was much better than the valve modification methods of increasing shot count.

Shoot Smart. Shoot Safely.

Poorman Plinker