Finally clicked on your link there.....that IS amazing! Two hundred + years ago, and they had that sort of firepower in an air rifle (firing a .46 caliber round ball, at that!!!).
Wow.
How would you like to be able to shoot a rimfire rifle or pistol that only makes 25% as much noise as a standard .22 LR gun? And no, we’re not talking about a suppressor-equipped firearm. CCI claims that its new Quiet-22 rimfire ammo “generates one-quarter the perceived noise level of standard velocity .22 LR rounds.” So this stuff is very quiet indeed, and it’s also affordable — a 50-round box sells for under $4.00 at major online vendors.
http://bulletin.accurateshooter.com/2011/12/new-quiet-22-rimfire-ammo-from-cci-just-68-db-of-noise/
I have seen if available for $2.69 per box of 50.
The part I can’t wrap my brain around is getting 800 psi out of a two hundred plus year old “bicycle style” pump. My fancy, modern, electric air compressor starts smoldering at around 95.