Quackenbush Number 7 BB gun: Part 2
by Tom Gaylord
Writing as B.B. Pelletier
Quackenbush Number 7 BB gun.
This report covers:
- Test 1 — 4.4mm copper-plated lead balls
- Test 2 — Avanti Precision Ground Shot
- Test 3 — 4.55mm zimmerstutzen balls
- BBs stay in
- Cocking effort
- Trigger pull
Today is more for me than for all of you. Today I test the velocity of my Quackenbush Number 7 BB gun. If you read Part 1 you know that I only discovered this gun works while researching that report. Until then I thought it shot an odd size shot that I would have to source from an industrial supply house as a ball bearing. But it was made to shoot 0.175-inch lead BBs, so all I had to do was find some of them. Well, that isn’t easy, either. Fortunately I used to shoot zimmerstutzens and other odd ball-shooting airguns, so I have some oddball stuff laying around.
Until the day I wrote that last report I didn’t know I could shoot this airgun, so I’m learning about it right along with you. I showed you how the BBs load in Part 1. Today I will test the velocity of two different lead balls of slightly different size and one additional surprise. Let’s get right to it.
Test 1 — 4.4mm copper-plated lead balls
In the 1990s when I was writing The Airgun Letter, there was a pawnshop in South Carolina selling Haenel 310 ball-shooting rifles imported from the former East Germany. Along with the guns, they also brought in a huge supply of copper-plated lead balls. I bought a lifetime supply of these balls and I still have plenty of them on hand. Upon reflection, I guess that’s a good thing, huh?
These copper-plated 4.4mm lead balls are really just slightly smaller.
The label says they are 4.4mm, but you know me. My caliper measures them at 4.39mm which is 0.173-inches. That puts them at the high side of today’s steel BBs. But it also makes them 0.002-inches too small for this airgun. They fall deep into the breech when loaded, but so far all have worked. They weigh between 7.5 and 7.8 grains, so we know the velocity is going to be lower that it would with steel, but since I would have to BB-gage every BB to find BBs that are big enough to shoot, I guess that doesn’t matter.
I shot 10 balls for an average velocity of 245 f.p.s. So the velocity is about that of a Daisy 499, but since these balls are about half again as heavy as steel, the Number 7 is a more powerful BB gun.
The velocity ranged from a low of 217 f.p.s. to a high of 256 f.p.s. Besides that one slow shot, all other shots went 242 f.p.s. or faster. So, 9 of the 10 shots ranged from 242 to 256 f.p.s., which is just 14 f.p.s.
Test 2 — Avanti Precision Ground Shot
Knowing the size of the lead balls gave me an idea. I knew that Avanti Precision Ground Shot runs large, so I measured 4 of them. Three were 0.1735-inches and the fourth was 0.173-inches. That’s the same size as the lead balls, or just a little larger. In fact 0.1735-inches is 4.4mm on the nose. They weigh only 5.5 grains, so they will be faster. Knowing they fit the breech, I tried them in the gun.
Ten Avantis averaged 296 f.p.s. with a spread from 291 to 306 f.p.s. That’s just 15 f.p.s., with no anomalous shots. Based on that, I’m going to try these in the accuracy test, too.
Test 3 — 4.55mm zimmerstutzen balls
This is where my fascination with zimmerstutzens pays off. Back when I had a couple zimmers I never passed up an opportunity to buy the lead balls for them. Even if they weren’t the correct caliber, I still bought them, because I never knew whether I might own one in that caliber one day.
These number 12 zimmerstutzen balls are 4.55mm in diameter.
Most people think all zimmerstutzens are just one caliber — 4mm, but the truth is there are more than 20 calibers, ranging from 4mm to 5.45mm. Not all of them are currently being produced, but shooting zimmerstutzens is still an active sport in Germany. I have several calibers of zimmer balls but the ones that excited me for this test are the ones that measure 4.55mm. I haven’t used them in 20 years, but today I opened the tin and went to work.
These balls measure 0.179-inches or 4.54mm in diameter. They weigh between 8.5 and 8.7 grains, so they are going to go slower. But they probably fit the bore of the gun much better. I shot them already a couple time, so I know they work.
These balls averaged 202 f.p.s. and ranged from a low of 134 to a high of 216 f.p.s. The low velocity was just one shot, and the next slowest shot went 195 f.p.s.
BBs stay in
Given the unusual loading procedure I showed in Part 1, I wonderded if the BBs were secure in the gun, or would they roll out when the muzzle is depressed. I loaded the gun and bumped the muzzle on the carpeted floor and the BB stayed put. That’s good enough for me.
The Number 7 is cocked by pushing the barrel straight back. It takes 45 lbs. of effort to cock this BB gun, which means they were probably usually cocked by pushing the muzzle against something — not by pulling it back.
The trigger is single stage and the gun has a direct sear. It releases with 8 lbs. 15 oz. of effort. Tha;’s my definition of a heavy trigger! It is free from creep though.
The Quackenbush Number 7 creaks and groans as it is cocked and shot. The trigger is stiff and crude and the sights are nothing to get excited about. But the fact that this old gun even works at all amazes me. It started out as next to nothing and now, nearly a century later, it’s an ancient next-to-nothing. It’s too lightweight and flimsy to work well, and yet it works just fine. I guess that is the attraction.
Next up will be accuracy. I’m not hoping for much, but you never know.