Gunsite had one of the best targets I have ever seen for teaching guys to track their sights in recoil. It was basically a plate rack that you shot on end starting with a 10in (or so plate), then an 8 in behind it, 6in, 4in, 2in etc in descending order. It was great and I have never seen it offered commercially. Build it so you can actually disassemble and mail it without having to go freight and every range in America would buy one once the word got out.
Are the plates in a line perpendicular or parallel to the trajectory of the bullet?