Has anybody made a diesel gun?

[john.k]

The error in using any kind of spring gun is that an increase of pressure acts against the pellet and the piston to retard ,or actually drive back the piston......thereby acting as a sort of safety valve..................so ,for the system to work ,at least you would need some kind of double diameter piston setup,so that the increased pressure due to fuel ignition did not act on the full area of the main piston,but on a reduced area of the smaller piston.....and as mentioned this makes the gun a firearm,and restricts sales ,whereas airguns can be sold freely in most parts of the world............If firearms are OK,then why not a much cheaper .22 rimfire.

[Multigunner]

There was a German diesel airgun marketed decades ago that used glass ampules of veterinarian grade ether, which apparently was easy to buy in Europe, probably from a farmers co-op.
I think they loaded the ampule into a chamber and it broke as the lid was screwed down tight. Each ampule held enough for several shots.

If a fuel is used that may not fire off easily in cold weather, or gave inconsistent velocities when dieseling, I would suggest a piezo electric ignition that tripped as the piston moved forwards.
It would also allow firing at a lower compression ratio, thus lighter spring loading.
A balance might then be achieved where the piston was blown back to self cock with each shot.

[W.R.Buchanan]

LB: that little Barakuda attachment on the side of the HW35 is worth more than the gun itself now. highly sought after by Airgun Collectors.

The seals that blow out on these guns are not the piston seals. The guns in question including both my 1978 guns are leather.

The seal that blows out is the breech seal,which is essentially a Teflon O ring. I have a drawing somewhere and have made them while waiting for replacements. Not hard to make. I have also used Delrin.

Randy

[Ozark mike]

Potato gun well kinda runs on ether or any flammable vapor I guess we'll call it the Otto gun haha or maybe a nuclear powered rail gun. I guess anything is possible

[AllanD]

Walgren's drug store sells 91% rubbing alcohol. It burns fairly good.

You can increase alcohol content by placing a bottle in a freezer for several days, water will settle out and freeze into a layer of ice at the bottom of the bottle, what you pour off the top will be nearly pure alcohol.
I've used a similar method to remove water from heating kerosene . I set a plastic container outside for several days in freezing weather till ice forms at the bottom. What rises to the top burns clean and bright in my oil lamps.

It would be much easier to buy dry gas at the auto parts

I have tried experimenting with adding a tiny amount of Kerosene to the back of the pellet with an insulin syringe (my father's), but I quickly switched to applying lighter fluid and using a Q-tip to apply the correct amount....

Too much creates a soot fouled barrel the exact right amount produces a sonic crack and some barrel leading, but as my RWS45 177 rifle would already penetrate a squirrel diagonally with Beeman Magnum pellets out past 50 yards and the fact that about half the pellets had their skirts turned inside out or otherwise disintegrate at the muzzle, I really didn't see the point in continuing..

Because a skirt-less pellet rarely flies true.