2 Q's: Turning Radius & Tongue Weight

the only way you're going to get a turning radius number for any given TV/TT combo is to hook it up and go see how tight a circle you can cut before something makes contact that shouldn't. No way to calculate that. Some can go til the bumper contacts the A frame, some might bind elswhere before that point. It really is only useful in helping get the feel of how tightly you can turn. As someone already pointed out, we don't measure all the turns before we take them anyhow. I try to look ahead and layout my difficult turns visually and shoot for the outside edge that will give me the best line. It really is mostly feel. For the first few years I had two dots drawn on either side of the center line of the trailer that I could reference in my mirrors. When I could line up those dots along the side of the truck looking in the mirror it was time to stop decreasing radius. Works great for getting the feel of how sharp you can turn. Find an area with some room, put the trailer at impending bind relative to the truck, sit in the seat and make a mark on the front of the trailer in line with the truck. When you see that dot getting into your view, don't go sharper. No sin in backing up sometimes.
And remember when making a turn with limited room inside, don't straighten the truck out until the trailer wheels clear the apex. Hold the turn AFtER the turn. Sort of counter intuitive, but when you straighten too soon, it pulls the tongue closer to the inside rapidly, and brings the trailer wheels closer insider, and sooner.