The more of these things I see happen the more I'm convinced that they're not really "records" or "achievements" beyond "achieving" the confirmation that a trajectory occurs.
If you create even a basic hit probability tool in Excel, and put anywhere close to realistic best-case parameters into it, you're going to see very quickly that 1 mile has some potential for semi-practical application, but by 2000-2500 yards, you've wandered far enough into the land of diminishing returns with hit probability that you're playing 3D roulette. Sorry if I come across as a negative Nancy here, but I just don't see the point. If you want to throw shit 5 miles, bump up the caliber, level the base, put a quadrant sight on it, and sling some HE with blast radius. Toodling around with shoulder-fired stuff is pissing in the wind.
IMHO it would be cooler or more fun to tape off rings (50, 100, 200yd for example) around a target post and fill out your Form 1 for a DD and have mortar competitions where each competitor has a specific color shell with a GPS in it. Send 5-10 rounds for score at several different targets/distances. If you're gonna spend thousands of dollars for some goofy ELR shit....