Crosman's fabulous trigger!
by B.B. Pelletier
When you think of great airgun triggers, Crosman is probably not the first company that comes to mind. But, are you aware that they designed a trigger that for many years was one of the top target triggers around? Probably not, because this trigger was found on their model 160/167 target rifle that came out during the period CO2 powerlets were suffering. All the CO2 guns made from 1955 through the late 1960s suffered from leaks, so CO2 got a bad rap and CO2 guns were largely ignored. Which is why in the 1990s airgunners everywhere began discovering what wonderful guns they had ignored, and none more than the 160.
The 160 trigger is adjustable
I addressed the Crosman 160 when I reported on the QB 78, so read that report to catch up on the rifle. Today, I want to look at just the trigger. It's adjustable for pull weight, sear engagement and has a trigger stop.
Do NOT disassemble any part of your gun unless you are 100% positive that you can put it back together again!
It came from a crossbow!
When I read Sir Ralph Payne-Gallwey's excellent book, The Crossbow, first published in 1903, I was stunned to see the ancestor of the Crosman 160 trigger in a military crossbow of the 1400s. The trigger is based on a rotating sear called a nut. Back then the nut was made from animal horn, and hundreds, if not thousands, have survived to this day. Crosman used steel or sintered iron - I can't tell which.
From Payne-Gallwey's famous crossbow book, this illustration of the trigger nut illustrates how a vintage crossbow trigger works.
Getting to the trigger requires disassembly
To get to the trigger, you must first remove the action from the stock. The safety switch has to be taken out and the single-action nut removed and then the action and stock separate easily.
Once the rifle's action is out of the stock, two trigger sideplate screws can be removed. This exposes the internals of the trigger. If you have an original Crosman trigger, there will probably be iron filings inside the trigger box. Brush them out before proceeding. The QB triggers don't seem to have this problem.
Crosman's 160 trigger (a QB 79 target trigger clone is shown) has the same rotating sear as the crossbow trigger. The dark half-round part at the upper right holds the hammer until the trigger releases it to rotate out of the way.
All adjustments appear in the picture
Pay attention to that trigger picture. See the two small screws coming in from the upper left side? The top one adjusts the amount of sear contact area. The bottom one is the trigger overtravel stop. The spring at the bottom is the trigger-return-spring adjustment that also regulates the weight of the trigger pull. The trigger shown is a modern copy of a 160 trigger from a QB 79 target rifle, and the first stage is built into the trigger blade, which is spring-loaded to move back and then stop as your trigger finger tightens.
The large pin with a spring around it at the right is the safety mechanism. The safety lever had to be removed to get the action out of the stock. Even with the sideplate off and the internals exposed like this, the trigger can still be cocked and adjusted, which makes your job much easier. However, it is not necessary to remove the sideplate to adjust the trigger.
Adjusting the 160's trigger
I adjust the sear contact first, leaving plenty of contact area. The sear responds well to lubrication, so you can have a good amount of sear contact for safety's sake. After adjusting the sear, I set the overtravel stop. It's possible to adjust this trigger so it will not cock and also so it cannot be fired after being cocked, so keep testing it as you go. The trigger-return spring is adjusted last, then the trigger is lubricated.
I lube the sear contact area with Beeman M-2-M moly grease. People used to warn that moly is too slippery for trigger lubrication, but that warning has faded today. After that, a drop of FP-10 goes on the sear pins on both sides of the sear so it can turn freely. The job is now done, and you can put the gun back together.
With lubrication and proper adjustment, you can get a safe trigger-pull in the 1-lb. range. It will go even lighter, but I think that's flirting with disaster.
If you own a 160/167 or a 180/187 with this trigger and you've never adjusted it, give it a try! You might be pleasantly surprised.