Good idea up front and I tip my hat to the gesture, but if someone is so deep in the rabbit hole of reloading that they need to use a labradar, they would probably buy one.
The fundamental problem I can see here in addition to what others have already said is that renting reloading equipment just goes against the grain of most people that reload.
A big part of reloading is spending money up front on reloading gear so you don't have to spend more money on ammo along the way (not withstanding current component shortage). But as stated I do tip my hat to the gesture.
If you really wanted work around some of the issues others have raised, you could have a thread here on the forum saying what days you are going to the range (this would assume membership at the likes of Kaitoke or Gladstone and that you head along on a regular basis) Turn up and spend the afternoon charging $10 or $20 to those who want to use it after you have set it up. You avoid all of the admin grief and stress of liability. I would probably pay that myself if I didn't have a chronograph and this is probably more typical of your target market.
$50 or $100 for a weekend would be a threshold where the hirer needed to do a lot of range time to make it worthwhile, which doesn't happen that often for most non owners of chronographs.
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