The North American Arms mini-revolvers are fascinating little pistols, incredibly tiny and capable of packing quite a little punch. I've wanted to test one for quite some time, but couldn't find any suitable ammo.
The ammo for this video was kindly supplied by Ammunition To Go (www.ammotogo.com)
The ammo in this test is Scorpion Ammunition's 40-grain jacketed hollow point in .22 Magnum (.22 WMR), UPC cod 8-13393-01664-6.
The test barrel length was 2", from a NAA Black Widow.
The ammo in this test is not specifically designed or oriented towards a short-barrel pistol. The only ballistic information I can find on it states that it is designed to deliver 1,890 feet per second, unquestionably from a rifle. A 2" barrel could not possibly deliver that type of velocity, and in my testing the 2" barrel delivered an average of 1,125 feet per second.
Note, that's about the same speed (or a little more, actually) than Hornady's Critical Defense or Speer's Gold Dot Short Barrel loads in .22 Magnum. However, with those rounds, the bullet has been optimized to perform at the slower pistol velocities, whereas I suspect that with this Scorpion ammo, the bullet has been optimized to perform at rifle velocities.
I used ClearBallistics synthetic ballistic gelatin to determine the penetration and expansion characteristics.
Note: I'm not making any claims for these videos other than that these are the results I achieved, in my own testing, from the stated pistol(s). I have no intention to make a blanket endorsement or indictment of any product, only to review and report what I found in a given instance. Obviously it is incumbent upon each individual to conduct their own research and make up their own mind about which defensive ammunition is best for their own purposes, in their own firearms.
The standards I use to judge bullet performance are the standards established at the 1987 and 1993 Wound Ballistics Conferences, and subsequently adopted by the FBI.