Dial calipers don't usually read to tenths and it will cost several hundred dollars to purchase one that does. For that degree of accuracy we typically use micrometers. For hand loader purposes, a caliper that reads to thousanths is good enough for almost any chore.
I don't know most reloaders, only myself a few others, but we all use "made in China" dial calipers that seem to be made in the same plant no matter the label of Lyman, RCBS, Midway/Frankfort, Harbor Freight, etc. All of them seem to do a fine job for our needs even though they are not up to the durability standards of serious machinests.
A 6" stainless steel dial or digital caliper from Harbor Freight can be had, on sale, for as little as $15. I have two of each type (do some home shop machine work as well as reloading) and all four read nearly dead on with my precision standard gage blocks so I am satisfied with them. For normal use the digitals are a pleasure to use but are worthless if the battery is dead so I use the dial type most often.
If you wish to spring for higher quality you may find some high grade Starrett, Brown & Shape or Mitutoyo calipers on eBay. That's where I got my B&S .0001" reading mike and it's perfect.
I have a digital caliper that is exactly the same as the RCBS, Lyman, Dillon, Frankfort Aresnal. I got them on ebay for $25 with shipping. 99% of all reloaders only need .001 incraments. Mine will read to the thousands and then go in 1/2 a thousanth as well.