You might look at the vortex strikefire. I got mine from opticsplanet for $135 shipped. It works great on the 15-22 and its rated for .375 h&h mag. I have mine on my sig516 right now. Holds a zero and comes with a 2x magnifier. The dot is plenty visible in bright sunlight. I usually switch over to the green dot when its real sunny out. I think it has 10 brightness settings.