You’re building a tank for no reason. There is no point in a bull barrel, other than keeping it cooler during repeated target shooting. If I were you I would get a 16” pencil barrel if I could find one (Faxon maybe, they used to have a 16” rifle gas too) and keep it as light as possible. You won’t be doing full auto, mag dumps or any other nonsense so why buy something that doesn’t fit the bill. Get a light 1-6 or 3-9 power scope and done.
Put it this way. If I ask you for a screwdriver and you hand me an 8lb sledgehammer, I may be able to get the job done but I will be way more tired by the end.
ps. Not only have we done that but we also lose money to a board member regularly at meets for a 14.5” 5.56 with a red dot out to 450.