Some years ago, I did a related test and chrono'd both .25 ACP and .22lr SV from two pocket pistols with similar length barrels.
Neither was a powerhouse. The .25 had a lower avg velocity but a heavier slug (50 grs.) and thus slightly more energy than the .22 (40 grs.). The difference was 8 ft.lbs. (64 to 56). The velocity of the .25 was right at published velocity of 760fps. The SV .22s chrono'd at about 800 fps.
The guns were a Bernardelli .25 (think Baby Browning) and a S&W 317.
"Only hunting and mountain climbing are sports. The rest are just games." - R.Ruark
NRA Life Member