Crosman 2240 conversion to air: Part 4
by Tom Gaylord, The Godfather of Airguns™
Writing as B.B. Pelletier
Crosman 2240 conversion to air: Part 3
Crosman 2240 conversion to air: Part 2
Crosman 2240 conversion to air: Part 1
R.A.I. Adjustable AR Adapter for Crosman 2240 pistols: Part 2
R.A.I. Adjustable AR Adapter for Crosman 2240 pistols: Part 1
WARNING: This conversion changes the operation of the pistol to use air at up to three times the pressure it was designed for. The parts that are installed are strong, but there are other parts in the gun that aren’t changed and could fail when subjected to the higher pressures. Pyramyd Air advises against making such a conversion. This report is for information, only.
This report covers:
• Sight-in at 12 feet
• Back to 25 yards
• End of the test
• Ft. Worth airgun show update
• Boot Campaign
Today, we’ll look at the accuracy of the 2240 on air at 25 yards. I’ve installed a 14.50-inch Crosman barrel on the gun, which boosted the velocity, as we saw last time. It also may have boosted the accuracy. Let’s find out.
The UTG Pro 6-Position Adjustable Stock has been remounted using the R.A.I. adapter. So, this is now a handy carbine.
I’m filling the pistol to 2250 psi, because I learned that was necessary when using the factory valve and a heavier striker spring. I get exactly 10 good shots per fill, which works well with my 10-shot groups.
For a sight, I installed the Tech Force TF90 dot sight that was used to test the Hakim rifle at 25 yards. We saw in that report how well this sight works, so it should work just as well on this carbine-sized gun I’ve assembled.
I sighted-in with 5 shots at 12 feet, and the gun was ready to shoot at 25 yards. I’ll show the sight-in target and explain it, so you can understand how this close sight-in works.
Sight-in at 12 feet
I sight-in at 12 feet because it’s safer. I know I’ll be on paper that close to the target, and I also know where the pellet needs to strike to be on at 20 yards. I used to sight-in all the rifles we sold at AirForce Airguns this way and was always on-target when I backed up to 23 yards. To learn more about this method, read this article.
What I’m looking for is the pellet landing in line (left and right) with the center of the bull, but as far below the center as the center of the sight is above the center of the bore. In other words, if you were to walk up to the target until the muzzle was touching the paper and center the dot (in this case) on the bull, where would the pellet strike the paper?
When you’re 10-12 feet back, the impact point doesn’t change much from that. But when you back up to 20 yards (20-30 yards, actually) the pellet rises up on the paper and ends up close to the aim point. It isn’t exact, but it’s the fastest way that I know to sight-in a pellet rifle.
My sight-in pellets were hitting the target a bit high, but not too high. Once they were centered, I left the sight where it was set and just backed up. I sighted-in with Crosman Premiers.
The first 3 pellets hit to the left of center. I adjusted the sight, and shot 4 hit to the right of center. I adjusted back to the left, and shot 5 was close to center. These are hitting too high at 12 feet, but I’ll use the setting as it is.
Back to 25 yards
The first group was fired with 14.3-grain Crosman Premier pellets. The first 3 pellets hit high and right of center. I don’t know how the rest of them hit, but you can see this is a fairly well-centered group of 10 shots. It measures 0.918 inches between centers, which isn’t too bad for a small gun like this at 25 yards. Remember — I’m shooting 10 shots instead of only 5.
Again, I must comment how nice and clear the TF90 sight is. It really holds a tight group — even though the target appears very small. That makes it a confidence-builder.
Next, I tried the JSB Exact Jumbo RS pellet. These often do well in lower-powered airguns. Remarkably, they went to the same point of impact as the Premiers. That means I don’t have to change the sight settings when using either pellet. This time, 10 RS pellets made a 0.763-inch group! That was very good, I thought. Especially given that I was using a dot sight!
End of the test
I’d planned on trying Beeman Devastator pellets next; but when I filled the gun, I noticed a leak at the joint of the HiPAC tank and the pistol’s tube. It was a fast leak and obviously the o-ring wasn’t doing its job. I tried oiling the gun with silicone chamber oil and refilling it, but the leak didn’t stop. So the test was over. I have to find out the problem and fix it if I can.
I do note that the pistol leaked down to 1750 psi and stopped. When I refilled it, the leak was much slower, so the oil may have done something. I think the o-ring and groove need to be cleaned and the tank installed again. But we’ll see.
At any rate, today’s test shows promising accuracy. It may not have been complete, but I’ll return to test the gun again at 25 yards. I plan to mount the TF90 on the Crosman 1077 next, so it may be a while before I get back to the 2240.
Ft. Worth airgun show update
The hotel is filling up fast for the show. Don’t forget to come to the reception at the hotel even if you aren’t staying there. It will be 7 p.m. to 8:30 p.m. Friday evening. Nothing fancy — just a chance to meet and talk about airguns before we set up Saturday morning.
I’ll be taking a caravan of people out to the range Friday afternoon from the hotel at 4 p.m. The range will be open earlier for people who want to get out there by themselves, but please tell me you are going, because this range is private. They need to know you’re coming or the gate will be locked.
We plan to start the door prize and raffle drawings very early after the show opens, and they’ll be held periodically throughout the day. Get there early and buy your raffle tickets for a chance to win a Walther LGV Competition Ultra, an AirForce Airguns CondorSS or a Hatsan AT44-10 Long QE! Since this show will probably not top a thousand attendees, you’ll have a real chance to win one of these fabulous rifles. And everyone who pays admission gets a chance to win an Air Venturi Bronco and a Benjamin Trail NP2 door prize!
Another group coming to the show is the Boot Campaign — a Texas-based nonprofit organization dedicated to the military (past and present) and their families — cultivating awareness, promoting patriotism and providing assistance.
Also, American Airgunner TV host Rossi Morreale will be attending the show, as he’s interviewing the ladies from the Boot Campaign.
I’ll have more news about the show as it develops.