The Lucky Gunner page for 9mm Parabellum, again at the time of this writing, shows 220 choices available. A massively wider variety also means there is a larger variation in price, with price per round from $0.15 USD to $1.95 USD (£0.12 GBD to £1.52 GBD). Hollowpoint ammunition starts at around $0.27 USD (£0.21 GBD).

Okay, what does this tell us? That one can get rounds for practice and plinking as low as $0.17 USD for the .22 WMR, and $0.15 USD for 9mm Parabellum. Ammunition that I consider to be suitable for defense (an entirely subjective decision) can be had for $0.17 USD in .22 WMR, and $0.27 USD so far as 9mm Parabellum is concerned.
So, fairly close although the .22 WMR has a decided edge. But the above comparison troubles me as there are far too many manufacturers in the mix. We are talking about bare basic hollowpoints for defense, but what is to say that the cheapest .22 WMR is far better in quality than that for 9mm Parabellum? Or vice-versa? Your $0.30 USD per round for .22 WMR might get you a very respectable and relaible load, while the $0.27 per round for cheap 9mm Parabellum hollowpoints may get you crappy handloads some guy in his basement is trying to get rid of because 20% or more have wet primers and won’t fire.
To control the variable on quality I decided to only consider products manufactured by Winchester Ammunition, which offers a product line I have always found to be reliable and of good quality. If we take a look at ammunition from one manufacturer, we should be able to smooth out fluctuations in reliability and craftsmanship.

As mentioned previously, the cheapest Winchester ammunition offered on the Lucky Gunner website for .22 WMR, at least at the time of this writing, also happens to be a load suitable for defense. The box states that it is a jacketed hollowpoint, but I would have to say that it is really a semi-jacketed hollow point as some bare lead can be seen at the tip. Cost per round is $0.17 USD (£0.12 GBD).

The Winchester products in 9mm Parabellum are much pricier, as you might imagine considering the difference in size of the bullets. The least expensive Winchester ammunition that I would consider to be suitable for defense has a price per round of $0.44 USD (£0.44 GBD).

If one considers two shots of .22 WMR to be a suitable self defense option, then there seems to be some advantages to the handgun pictured at the top of this essay. The least expensive ammunition offered by Lucky Gunner in that caliber, which one would choose for practice, is also the very same load that could be chosen for defense. This would mean that someone could be training with the same ammo they carry to stop a violent criminal attack, which is not something to be dismissed out of hand. Even considering that two cartridges are expended with every pull of the trigger, thus doubling the cost per trigger pull, one would still save some cash by using the new gun.
Does that mean I have changed my mind and will buy one of those slick little revolvers? No, still won’t. The main reason being that I have a sizable investment in .38 Special, .357 Magnum and 9mm Parabellum. There just isn’t any real advantage to be gained by switching this late in the game. But that is only my personal situation, and it doesn’t mean that other people won’t come to a different conclusion.
Thanks for the analysis!
I suppose, then, that this gun might possibly suit someone who doesn’t own other handguns, is intent upon doing a great deal of practice and particularly concerned about ammunition costs – perhaps not a big market.
I’m with knirirr – anyone who practices enough to care about the 10 cent difference between two rounds of .22 mag and one 9mm is probably not going to carry a .22 mag for self-defense anyway. It’s a Catch-22 (excuse the pun).
Let’s see: pull the trigger once, two shots fire. The ATF defines a machine gun as- “Any weapon which shoots, is designed to shoot, or can be readily restored to shoot, automatically more than one shot without manual reloading, by a single function of the trigger.” Own or carry at your own risk!
Good point!
I came here to say the same thing, but Jim beat me to it. Perhaps if the manufacturer split the trigger, similarly to how double barrel shotguns or rifles with double triggers are set up, but put the triggers side by side it would get around this issue. As it is, this handgun certainly fits the BATFE definition of machine gun better than a bump stock.