by B.B. Pelletier

Test data and photos by Earl “Mac” McDonald

Back in the 1990s, Dennis Quackenbush made a nice part of his living by modifying single-shot pistols from Crosman. In those days, there weren’t as many places to buy aftermarket parts, and Crosman didn’t have a custom shop. In fact, when Dennis and I were seated with Crosman’s CEO at an NRA Airgun Breakfast at the 2001 NRA Annual Meetings and Exhibits in Kansas City, Missouri, we introduced ourselves and he asked both of us what we did. Dennis told him that he made his living modifying Crosman single-shot pistols. “You sell them (the SSP 250) for $39 and I modify them for $125. I can’t keep up with all the work!”

To say the man was stunned is an understatement. I don’t think he believed Dennis, because he restated what Dennis had said, “You mean people pay you $125 to modify a gun that sells for $39?” You could hear the disbelief in his voice.

That man didn’t remain at the reins much longer. And his replacement, Ken D’Arcy, instituted the Crosman Custom Shop a few years after he stepped in. But that did not diminish the number of aftermarket places that modify Crosman airguns and make parts for owners to install. If anything, the number of places increased, though I would not say that it was in response to the Crosman Custom Shop starting up. But it was and still is a direct result of the openness of the Crosman Corporation toward their customers, by providing parts and information that support their guns.

For several years, one of the most popular modifications Dennis made was a steel breech for the Crosman 2240 single-shot pistol. Not only is it stronger and more rigid, it also allows for the installation of a scope — something that most home tinkerers will want to do. And Dennis switched the bolt handle to the left side for right-handed shooters, because they want to continue to hold onto the pistol while they load it. People who don’t shoot these pistols don’t understand that desire, but it only take 15 minutes with one and you understand completely. That one change may have been his greatest contribution, because it showed everyone what a little thought can do to enhance the operation of an inexpensive airgun!

Many of the handguns Dennis built on Crosman frames are righteous thumpers, with power levels far beyond anything Crosman ever envisioned. Dennis has made several guns on this 2240 frame that achieved 100 foot-pounds of energy at the muzzle, and I’ve personally witnessed one that produced 300 foot-pounds. So, like the modern AR, there’s no limit to what you can do with one of these flexible air pistols.

But in this report, we’re going to look at something a little closer to the original gun. It’s a .25-caliber pistol that has the steel receiver from Dennis and a 10.5-inch barrel that he rifled. In terms of power, it’s been left pretty close to original; so it gets a decent number of shots. Because of the large caliber, they don’t go very fast.


The Quackenbush .25-caliber pistol is built on a 2240 frame. It has a steel receiver, and the bolt is on the left side for easier loading.

There are no open sights, as Dennis envisioned owners would want to scope the gun. The receiver has an 11mm dovetail cut into the top. Since the frame is from a 2240, it readily accepts an add-on carbine stock that so many shooters seem to prefer. Certainly, when you put a heavy rifle scope on the pistol, the stock is the best way to go!

Mac reports that the pull length with the carbine stock is 16.3 inches, but the angle of the grip makes it feel shorter. He says it fits him well, and he usually likes a rifle with a pull length of 13 inches. I looked at the pictures he sent and see that the scope hangs back behind the receiver on this gun. That may be why the long pull doesn’t feel so bad. Also, the gun is very light, at only 48 oz. in the scoped pistol configuration, so there’s not a lot of weight hanging out front. The shoulder stock adds another 13 oz.


The optional shoulder stock is something nearly all pistol owners have.

Dennis didn’t number all of the guns that he made, but partway through the production he began to put his own serial numbers on them. His last gun carried the number 850. Mac’s pistol is numbered 509.

Though Dennis no longer makes complete guns, according to his website he still does make the parts for them so owners can modify their own guns. The velocity of the .25-caliber pistol is approximately the same as the 2240 that it was modified from when shooting a 14.7-grain .22-caliber pellet.

The features of this modification are:
Steel barrel, receiver and bolt
The barrel is threaded into the receiver
The transfer port is in the breech instead of the barrel
The new steel bolt is larger than the pellet
The bolt contacts the pellet’s skirt — no probe is used

The pistol is 14 inches long without the shoulder stock, and 26 inches in the carbine configuration. The trigger-pull is a repeatable 43 oz., though some may find the trigger blade a bit too thin for comfort. The scope you see here is a cheap Simmons that Mac thinks was probably a rimfire scope at one time. It has a one-inch tube and fixed 4x magnification. The 32mm objective lens has a fixed parallax that Mac adjusted to 25 yards by turning the lens locking ring.

While many .25-caliber single-shots produce lots of muzzle energy, this isn’t one of them. Those guns are modified into PCPs, where this one is still a CO2 gun. It gives you a taste of a larger caliber without all the extra fuss and noise that a magnum blaster would have.

Mac tells me this pistol is quite accurate, and he loves the way it lobs them in. Next time, we’ll combine Parts 2 and 3 for a good look at the performance of this vintage Quackenbush airgun.


With the longer barrel and no open sights, this pistol looks slicker than the 2240 it was modified from.