Crosman sight system
The Crosman Precision Diopter Sight System.

Part 1

This report covers:

  • No cant
  • The test
  • Cocking
  • Sight in
  • One and only group
  • Discussion
  • Summary

Today I mount the Crosman Precision Diopter Sight System on the Crosman Challenger PCP 2009 and sight it in, in preparation for the accuracy test. I know the Challenger PCP 2009 is accurate, but how will it respond to this purpose-built sighting system?

It’s been two years since I last tested the Challenger 2009 and I had forgotten many of its characteristics. For starters, it is very quiet. My cat, Dale Evans, left the room when she saw I was preparing to shoot. She came back in half an hour later complaining that she couldn’t hear the shots, and how was she supposed to protest if she wasn’t aware of what I was doing? This air rifle is quiet. I wish I had recorded the discharge sound but since I didn’t I will guess it was around 81 or 82 decibels.

Challenger with sights
Crosman Challenger 2009 with the new The Crosman Precision Diopter Sight System.

I mounted the new sights and then I put the rubber eye cup on the rear sight. With that in place I don’t need the blinder to keep both eyes open. The cup makes the rear peephole very bright and easy to see. Without it the blinder is necessary for me.

Challenger rear sight detail
The only thing I did extra was to install the rubber eye cup that makes the rear peephole extremely clear and sharp.

Someone asked what the diameter of the rear sight tube is, so I measured it for you. It’s 0.940-inches in diameter.

No cant

I’m testing the new front sight with the 3.8 mm aperture up front. This is the one that sits square in the sight. There is no attempt to cant the sights today.

Challenger front sight detail
The Challenger PCP has a long dovetail that allows you to position the front sight wherever you want — on the dovetail. I put it at the end to get the longest separation between the front and rear sight.

The test

This is not an accuracy test. I just want to sight in the new sight system so I can do an accuracy test. Today also allows me to re-familarize myself with the Challenger PCP. I found the two-stage trigger is quite positive with just the hint of creep in stage two. I can use it quite well, plus it meets the NRA/ Civilian Marksmanship Program requirements for a trigger for junior marksmen. Unlike precision rifles (the CMP/NRA term for world-class 10 meter rifles) that have no trigger-pull requirements, the triggers on rifles used by junior marksmen must break at no less than 1.5 lbs. (680.4 grams). The trigger on this rifle pulls 15 ounces in stage one and breaks at 1 pound 8.7 ounces. That’s about as perfect as things can get.

I shot only the Qiang Yuan Training pellet today, because back in July 2020 it was the most accurate pellet. It seemed the best way to proceed.

I sighted in and then shot a single five-shot group off the sandbag rest with the rifle rested directly on the bag.


The Challenger has a T handle that pulls straight back to cock the striker and move the bolt back out of the way. I find the rifle very easy to cock and load. The FWB 600 is easier to cock and pump, but to do it I have to pick it up off the sandbags. I don’t have to move this one to do anything.

Sight in

Okay I have replaced the original sights with these new ones — both front and rear. Is the rifle anywhere near the target? Because of that I went up to 12 feet and shot offhand. The first shot went into the bull I aimed at. The shot was low and a little to the right.

I love that Crosman has marked the sight adjustment knobs with the direction the shots have to move instead of the backwards German way. No making mistakes here, plus there are index scales to watch where the sights move.

Knowing that the rifle was on target at 12 feet, I backed up to 10 meters and rested the rifle on the sandbag. Shot two cut shot one a little higher which I expected. I adjusted the rear sight four clicks up and three to the left. For some reason the next shot seemed to go into the same group so I adjusted the rear sight up and right twice as many clicks this time. The next shot was a 10. Time to shoot a group.

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One and only group

Okay, the next five shots were fired without checking the target through the spotting scope — which you now know is a pair of MeoStar binoculars. Back in 2020 this rifle put five of these pellets into 0.097-inches at 10 meters. That was before the silver Chukram comparison coin existed for groups smaller than one-tenth-inch.

Today I put 5 of there Qiang Yuan Training pellets into a group that measures 0.121-inches between centers at 10 meters. It’s larger than the group from two years ago, but not that much. When groups get this small any error in measurement throws things way out of whack.

Challenger Chinese Training group
Today with the new sights the Crosman Challenger PCP put five Qiang Yuan Training pellets into a 0.121-inch group at 10 meters.


I have to say I think the image through the new sights looks sharper and clearer than the image through the old sights — the ones that came standard on the Challenger. I used the same 3.8mm front aperture that the old sights used, but in the new sights the bull looked smaller with more white space around it inside the aperture. No doubt that was because of the rubber eye cup making the rear peephole brighter.

The new sights adjust crisply and the scales on the sight body tell which way the adjustment was made. The bars in the front sight insert that was used for today’s test allowed me to level the rifle by lining up with the bullseyes on the rest of the target.

I don’t know if I will even test the canting option, as the rifle seems to work well when it’s truly level. Canting would be for when the rifle is hand held.


This was just a quick little test to see if the new sights are as good as the old ones or perhaps better. I think they are at least as good. Would I spend the money to change over to them? Nope. But if I were buying a new Challenger PCP — the one that only Crosman seems to be selling at present — I would want these sights to be on it.