Does you pistol have a safety lever on front of the trigger like a Glock? Are the eyes on the owl in line with the grip screw or perpendicular to the grip screw or looking at you? Is the top latch a single post or a double post?
If you have no safety lever on the trigger, if the owls eyes are perpendicular, if the top latch is a double post, you have a 3rd model IJ, which was designed for smokless powder.
I shoot my 2nd model IJ's with factory equivalent smokeless loads. It's not like I'm shooting 200 rounds in a range session, I MAY shoot a box a year through them. A 1st model I will not shoot though.