Power Adjuster for less than $1.00

There are a number of ways to increase power in the 2240. One way to do this that requires a minimum of tools and trouble is to preload the mainspring. The receiver end cap needs to be removed .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.

The following was performed with Crosman Premier Domed pellets off a bench at 7 meters with the chrono at 55 inches. The shot count stopped at the first shot under 400fps. The light preload cost 7 usable shots, but improved the performance in Extreme Spread (ES horiz-x-vert), Max velocity and Standard Deviation. Overloading cost 19 usable shots and did not perform better than a moderate preload.

Poorman adjuster with 0 load (factory setting) ES 1.98x1.94 - 41 shots HI 447 AVG 426 SD 15

Poorman adjuster with .066 load ES 1.67x1.5 - 34 shots HI 453 AVG 427 SD 11

Poorman adjuster with .271 load. ES 1.85x1.85 - 22 shots. HI 451 AVG 427 SD 18

Granted loading the mainspring caused the already heavy trigger weight to increase. We have already determined the effect of trigger weight on accuracy and it cannot be discounted in this test either. So, the decrease in accuracy from loading the spring may be caused by the increase in trigger weight.

The preload of the mainspring was done by placing #4 washers inside the receiver end cap. When shopping for washers it is best to bring the end cap with you to find the right size.

I used these washers to add preload to the striker spring.

For more precise adjustment I would use Brass or Stainless... half as thick.

Looks like you would not need more than 8 of these washers to overload the spring tension. $0.72

Shoot Smart. Shoot Safely.

Poorman Plinker

#poweradjuster