Beeman QB Chief precharged pneumatic rifle: Part 4
by Tom Gaylord
Writing as B.B. Pelletier
This report covers:
- Remove the stock
- The stock comes off
- The trigger housing
- Now to adjust the trigger
- Trigger stop screw
- Trigger pull adjustment
- Put the action into the stock
- Installing the safety lever
Today I will discuss adjusting the trigger in the Beeman QB Chief precharged pneumatic air rifle. I promised you a tutorial on the trigger and this is it.
Remove the stock
The first step to adjusting the trigger is to take the barreled action out of the stock. On this rifle that isn’t as straightforward as it sounds. There is just a single Phillips screw holding the action in the stock, and I trust you can all deal with it. But the safety lever on the right side of the triggerguard has to also be removed for the stock to slip off the triggerguard.
First uncock the rifle. To remove the safety, point the safety lever straight down and push the safety from the opposite side of the triggerguard. The large round surface on that side makes pushing it out with just a finger possible, though I get it started, then use a punch to get it all the way out.
The stock comes off
Once the safety is out and the stock screw is removed, the barreled action lifts out of the stock. Set the stock aside and turn your attention to the trigger housing.
The trigger housing
The trigger housing of this trigger is built to hold the operating trigger parts in place when the sideplate is removed. Back in the Crosman days when this trigger first saw the light of day that wasn’t quite as true. Some trigger were okay with their sideplates off while others wanted to dump their parts when the sideplate came off. The one on the test rifle worked fine with the sideplate off, which allows you to adjust the trigger easily.
With the sideplate off you can see the inside of the trigger.
Now to adjust the trigger
The first step to trigger adjustment is the cock the action. When you do the trigger and sear will be in full contact.
In this picture the action is cocked. It doesn’t look much different than two pictures back. But this time the sear is holding the striker that is under spring tension. The small screw at the top left, behind the trigger blade, adjusts the sear contact area. This picture shows too much sear engagement. Turning the 1.5mm Allen adjustment screw in will lower the trigger on the sear and reduce the contact area.
That picture shows everything you need to know about trigger adjustment. This is a positive sear engagement trigger, and adjusting it lighter means reducing the area of contact between the trigger and sear. The trigger return spring pushing the bottom rear of the trigger keeps the trigger raised so it will contact the sear. Don’t fool around with that spring, because it is needed for safe operation.
I only had to turn the 1.5mm Allen adjustment screw in a little to get the engagement I wanted. Some blue Locktite on the screw threads will ensure the screw stays put. If you want to use some Moly grease, put very little on the areas of the trigger and sear that come together when the rifle is cocked. It will be spread around as the gun is used.
I bump-checked the trigger for safety (cocked the action and tried to bump it into firing) and when I was satisfied it was safe I lubed the contact point with moly grease and adjusted the trigger stop screw.
Trigger stop screw
The trigger stop screw stops the trigger blade moving after the gun is fired. This gives an additional feeling of crispness to the trigger. Only finer triggers have this adjustment. In this unit it is the lower adjustment screw seen in all the photos.
In the pictures above the trigger stop is not set correctly. It’s too far back. Like the sear engagement, this screw only had to be turned a little for a perfect stop. Go too far and the gun will not fire, because the trigger can’t move far enough back to release the sear. So test it often and set it on the slightly loose side. Like the sear engagement adjustment screw, this one could use a little blue Locktite on the threads.
Trigger pull adjustment
There is one more adjustment. The trigger return spring has a screw adjustment that lightens the trigger pull a little. A slotted screw in the back of the triggerguard can be turned in or out to change this pull slightly. It’s right behind and in line with the spring. I like a positive return spring for the security it affords. The trigger is always going to catch the sear, if the return spring has good tension. I said earlier not to fool with that spring and now I’m telling you to leave the adjustment screw alone, as well.
Put the action into the stock
At this point the trigger is fully adjusted. Drop the barreled action into the stock and tighten the stock screw. Then install the safety lever.
Installing the safety lever
With a small screwdriver blade, push the safety plunger up out of the way, coming from the opposite side of the gun (the left side) as you simultaneously press the safety lever in on the right. The safety lever should be pointing down as this is done. The safety lever will catch the plunger and hold it in place, so you can reposition the screwdriver to push the plunger up more forcefully. At some point the safety will have clearance and you can push it back into the triggerguard easily. It takes longer to explain than to do.
To install the safety use a small screwdriver from behind and push the safety plunger up out of the way. I’m showing it without the stock for clarity, but the action would be in the stock when this is done.
There you have every step in the adjustment of the trigger on a Beeman QB Chief PCP. It’s not very difficult and the result is a very nice single stage trigger pull.
One final word. Though this trigger is a modern refinement of the Crosman 160 trigger, the 160 does have small differences. The modern trigger is easier to adjust and also easier to test after adjustment. I tell you this in case you try to step backwards and adjust a Crosman trigger with these instructions. It can be done, but that trigger isn’t as refined and easy to test as this one.