Ok, so I know I did stuff like this back in school, but I'm getting nonsense answers now.

I have a beam with one end bolted to a wall and one end supported on a roller. I can get the total bolt shear load easy enough and the roller reaction. I need to know what axial forces will be induced in the bolts by the bending stress in the beam though. I know that it will net zero, but I also know it's not so simple beacuse I get crazy big numbers.

Thanks in advance.

If one end is bolted and the other is roller-supported, it's not cantilever then, more like a fixed-roller supported beam - correct? The bolt stress will depend on a ton of things and assumptions, like the orientation of the bolt fixture (flat or sideways to a wall), number of bolts, bolt pattern, plate geometry and thickness.

One approach would be to use the fixed beam end and find your reaction moment, and work with you bolting pattern and flange from there. You could always refer to say AISC codes which have provisions for bolt sizing. If you do need the axial forces, you could assume your flange as as rigid plate and use leverage formulas with the found moment.

Just tossing some thoughts around, if you could give a screen shot or a sketch of your setup it may be more helpful.