not exactly sure but with the quick chuck my gun is 12-14"

lol. Ill try and post a picture later. I thought I would have issue with access tight places

But some how I Always make it fit...
yes it does use .498 chisel of which i have still not found a reliable bit yet im gonna try Ajax brand chisel next. I will keep yah posted on that.
Stay away from the GP.498 chisel there not worth a dime...
Ajax is the brand of quick chuck best suited for the gun I've been very happy so far, but it was a bit of a nightmare trying to source a nylon replacment washer for for my chuck. Larry at Ajax was a huge help and was able to figure out all the part numbers and even shiped me the $15 part for FREE (go AJAX)
This guns are really worth there weight in gold id like to get a 2x and 4x gun to make a set