My dad picked up an Unfired (Unfirable?) Stainless TP-70 in .25 ACP  with some weird characteristics and a low serial number. He got it for a very low price thinking he could tinker with it to get it running.

It wasn't stripping rounds from the mag, so he polished the feed ramp, with no improvement. He then looked at the breech face and noticed that it was machined in such a way that the rim of the round would be almost entirely surrounded with the slot for the round to slide up being to narrow for the cartridge. (instead of an upside down "U" it was an "O" with a small gap on the bottom)
The slide catch slot was also machined too far forward to catch on the lever even when the slide was fully pulled to the rear. Finally, the trigger is all weird, in DA, it will push the hammer to the rear, but never trip the sear. In SA, the trigger is only 2# so for the 9 shots he did get it to fire, the hammer would slip off the sear and follow slide home.

Now the real interesting part is the SN, which is "0xx P"

We are wondering if the very low SN followed by a P was a prototype, or if he managed to buy a $200 paper weight.

slide reads

Budishowsky TP-70
.25 Cal. Automatic Pistol
NORARMCO Mt.Clemens, Mich.

I am thinking a $200 paperweight.

Here is a link to the manual.

TP-70