It's been discused here at some length with a lot of speculation.
Given the apparent similarity in the two guns, frankly, I can't begin to imagine! That's one of a few reasons I'm sticking with my P32 for a while longer.
grumble, snort, grumble, mumble....didn't buy the P3AT at first 'cause no slide stop. Then found one for a good price and got it. grumble, mumble,.....still want a slide stop.
Have to use a Sherwin Williams paint stirring stick for a slide stop to work on mine. I remove the magazine, slip the stick in, hold upside down while pulling slide back until the stick drops between the slide and barrel. Then I can pull out the assembly pin.
Sure, sure, I've been told over and over I only have to pull the slide back a little to get the pin out. My 75 year old hands are still good but not like you young studs and I can't hold the slide long enough to get the pin out. Kel Tec should furnish paint sticks with all P3AT pistols. :roll:
grumble, mumble....still miss the slide stop.
P.S. It was Flyer who first suggested using a stick like that a long, long time ago on another planet we used to post on. I wonder if he will admit it.
Usually you have to retract the slide a bit to remove the assembly pin... the recoil spring is forcing the barrel lug against it, and it's hard to remove.
The official instructions say you need to retract the slide all the way, but in reality just a quarter-inch or less is needed.
If you can pull your pin out with the slide in full battery, I'd think you've either got weak recoil springs, or both springs aren't there... the AT uses a double-spring arrangement.
I'd give it a look-see.