I was doing a quick search on Google and ran across this post of yours from earlier in the year with no responses so I figured I'd give you a shout back;
I still have my AT85r from back in the day, 1999 if memory serves, though sadly it hasn't seen any paint in quite some time. When I was running it, I did figure out the key to near perfect operation: maintenance, maintenance, and more maintenance! I'm sure you figured this out as well, but the guys at the field (even other AT owners) told me I took it to new heights - every 6 games I totally tore it down, every 3 games I field stripped it. When I say 'game', I mean 15-20 minute trip on to the field....I might have gone a little OCD with this thing. heh. That being said, my best run was at a big game and I put around 700 rounds through it nearly constantly before being overrun (10-15 vs 2 in a bunker, we were bound to lose)
Long rant aside, I loved my AT and even when I moved on to other guns I always pulled it back out just for fun (and to scare the noobs because of how loud the thing was!). I attached a pic for you.
Hope there's a little nostalgia for you.