by Tom Gaylord
Writing as B.B. Pelletier
This report covers:
- A mechanical blowgun
- How it works
- Comparison to a blowgun
- Springs
- Shape of the gun
- Breechloaders
- Triggers
- Accuracy?
- Rare?
- DIY?
I was surprised several days ago when a couple readers told me they thought a bellows gun was some kind of pneumatic, after I had written i9n a report that it’s a spring gun. Today we will find out what a bellows gun is.
The bellows gun is thought to be one of the oldest airgun designs. Some writers say it may be older than the precharged gun. There is convincing evidence that bellows guns existed in the 1500s, which is when precharged guns are also thought to have started. They seem to have been made well into the 19th century — so their span of production is very long.
Bellows guns have shot several different projectiles like hard clay pellets and even lead balls, but darts are by far the most favored projectiles. Their darts aren’t like the airgun darts we see today. They are longer, larger diameter and their tails have long natural hairs plucked from game. Each individual dart was apparently regulated for accuracy by removing the hairs from its tail, one at a time. I guess this reduced their drag, and perhaps caused them to travel in a certain direction.
These darts also had one dark hair that was called a guide hair. It was used to orient the dart in the breech the same way every time it was loaded. Shooters found that by consistent loading, their accuracy improved. Schuetzen shooters do the same thing when they load their cartridge cases into the breech in the same orientation every time.
Darts for bellows guns were longer than today’s darts. They had one dark guide hair, so they were always loaded in the same orientation.
A mechanical blowgun
The bellows gun is simpler than the precharged gun because it contains no valves. That is a strong argument for this design being earlier than the precharged gun, since the valve I discussed in my report on The first pneumatic gun was state-of-the-art for its day. The bellows gun needs no valve because it doesn’t work in the same way.
How it works
You all know how a blowgun works. You hold the blowpipe to your mouth and blow air sharply through the mouthpiece, propelling the projectile out of the pipe. Your lungs are powered by your chest muscles — mostly by your diaphragm that pushes upward to force air out of your lungs rapidly.
A bellows gun uses bellows instead of lungs to do the same thing. You all probably know what bellows are. They are a simple wind pump that has a one-way air valve. The air comes into the air chamber when the bellows handles are pulled apart, but cannot leave that way because the valve closes. The simplest form of a bellows is two wood pieces held together by a pleated leather piece that forms a flexible airtight chamber.
Air is taken in through the one-way valve when the bellows are opened and it’s forced out the nozzle rapidly when the bellows are closed. Normally you use your hands to close the bellows, but in a bellows gun, a powerful V spring is substituted.
The bellows is a simple wind pump.
Comparison to a blowgun
The blowgun uses air that’s not compressed very much. It is the rapid application of the air that starts the dart moving in the blowpipe and continues the acceleration until the dart leaves the muzzle. Even with air compressed by only your lungs, the dart flies very fast. It’s almost too fast to see.
A bellows gun compresses less air than your lungs hold. There is less volume inside the bellows system than there is in your lungs, but it all gets used. It is almost impossible to exhale all the air from the lungs. So the two are roughly equivalent. But the bellows act faster than your diaphragm. So the small lightweight dart they propel goes out the muzzle at a respectable clip. I have no data on velocity, but I wouldn’t be surprised to learn that a bellows gun propels its darts at up to 300 f.p.s.
This may sound slow to airgunners, but remember — this gun is shooting darts! Darts have sharp points that stick deep in whatever target they strike. You don’t want a lot of velocity for them or you’ll never get them out of the target.
Springs
Remember the time frame for the first bellows system, because this is important to understanding its design. Coiled springs hadn’t been invented yet, so the bellows gun made do with V springs. One side of the bellows was anchored and the other side was free to move. It moved against a powerful V spring that was under tension, once the moving side of the bellows was caught by the trigger’s sear.
When the sear released the movable bellows side, it was forced together with the fixed side rapidly, resulting in a puff of air that was not unlike what you do with your lungs to fire a blowgun. Only the V spring acted quicker than you can blow, so the puff was stronger. The air was forced behind the projectile in the breech — in the same way you exhale a puff of air into the mouthpiece of a blowgun to propel a dart.
So, the bellows gun is a spring-type airgun. The bellows takes the place of a piston and compresses far more air to a much lower pressure.
Shape of the gun
There has to be room inside the gun for the bellows. The buttstock was made much wider and was hollow inside to house the bellows. All bellows guns have this shape. Once you have seen a couple you will be able to spot them every time you encounter a different one.
The butt of the bellows gun is both deeper and wider to accommodate the bellows inside. The square shaft fits a long spanner that’s used to cock the gun. The split wood at the bottom of the butt is for disassembly of the butt to maintain the bellows.
Most bellows guns look like this. A deep wide butt and wood to the end of the barrel.
Breechloaders
All bellows guns I have seen have been breechloaders. And several have used the wood forearm of the stock to serve as the spring to close the barrel after loading! The long wood forearm actually flexes when the barrel is opened. This is scary when you are handling a gun you know to be several centuries old, but it does work.
Triggers
Triggers are where the bellows gun excelled. They are nearly always double set triggers (I have never seen any other kind) with the rear trigger being pulled to set the front trigger. These triggers are the ones that brought the term “hair trigger” into existence. They can be adjusted so light that they will fire when the gun is rotated from the horizontal to the vertical. The weight of the trigger blade by itself is enough to set them off. The front trigger blade is usually so thin that it bends as pressure is applied.
Accuracy?
I read a lot about the stunning accuracy of bellows dart guns, but I reserve judgement until I see it for myself. I have read accounts of placing one dart on top of another at 45 feet. Maybe that’s possible, but as I said — I reserve judgement. No doubt they seemed accurate compared to what went before, which was nothing.,
Rare?
I have seen about 20 bellows guns in my time as an adult airgunner. Some of the guns I have seen may have been the same guns in different hands. They certainly are not that common. I think there must be several hundred that still exist somewhere, so to answer the question — yes, they are quite rare.
And they are fragile. The passing centuries have left most bellows guns is a very fragile state. I have heard of one or two that have been restored to working condition, but even then I think they are just used for special occasions. They are not everyday shooters.
DIY?
Of all the airguns that exist. the bellows gun is one of the easiest to replicate. I have seen several homemade guns that worked quite well. They all lacked the sophistication of the antique models, but they did function well. On 50 psi they will send darts through Luan wallboard with ease. If you are looking for a project airgun to make, this would be the place to begin.