THE WORLD LEADER IN HIGH-PERFORMANCE PARTS FOR CROSMAN & BENJAMIN AIRGUNS
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MAGNUM RIFLE ADJUSTER INSTALLATION & ADJUSTMENT
Discovery, Maximus, Challenger, 2260 and Fortitude
MAKE SURE GUN IS UNLOADED, UNCOCKED AND EMPTY OF PRESSURE BEFORE REMOVING OR INSTALLING PARTS
1 ) There’s a spring-wire behind the trigger you need to pull forward with a pick to be able to pull out the safety button. Take the stock-screw out and wiggle the stock off if it doesn't come off easily. The rifle adjusters require a 3/8" long rear trigger frame screw. Any shorter may strip the threads on the screw or adjuster, any longer will hit the threads on the adjuster knob. A 3/8" alloy socket-head screw is included, it requires a 3/32" hex wrench (not included) to install.
2 ) Remove the rear trigger frame and rear breech screws. Remove the tube plug which is where the adjuster will mount. It usually falls or lightly ejects out if you don't hold it while removing the screws.
Install the adjuster with the threaded knob removed. Install the mounting screws, don't tighten either until both are fully threaded in.
Place the hammer spring on the guide at the tip of the threaded adjuster knob. Make sure the spring goes into the back of the hammer as you thread the knob into the tube plug.
If you adjust the knob too far forward, the hammer will not pull back far enough to catch on the sear. Adjust to full spring compression with the gun cocked, stop when you feel the spring is fully compressed, do not force it further. Back the adjuster out two full turns, this is about the tightest setting that works smoothly. This would be the full-power setting for high-pressure PCP and HPA guns. For lower pressures and CO2 the spring tension may need to be lighter for the power level to peak. If too much spring tension is used at low pressure the valve will tend to close faster causing power loss. This is very common with CO2 models, especially at low temperatures where CO2 produces less pressure.
3 ) With a power adjuster, custom valve or stronger hammer spring it’s typical to have to cock the gun to get the valve to seal so it can be pressurized. Once pressurized this shouldn’t be necessary if there's pressure left before filling.
4 ) The more striker spring tension you have the harder it becomes to pull back the bolt. With a power adjuster, especially if using a stronger hammer spring, the bolt will pull back easier with your finger hooked around the front of the handle close to the breech. If done in one quick motion the bolt will pull back smoothly. If done slow or holding the handle further away from the breech the bolt may tend to bind or work rough.