If you use a rod or something in the bore to check it, make sure whatever you are using to compare is actually straight first.
For me I'd check by rolling it on a flat surface, or just visually checking with light while looking down the bore and twisting it.
I've got a 22-250 that has a mcgowen custom barrel on it, installed by a somewhat local gunsmith. I'm 95% certain the barrel is bent. Checked by chucking in up in my lathe. Dial indicator used to center both ends of the barrel in chuck/spider. Then move indicator 5" up the barrel and it's not centered. Look down bore while it's rotating and there's obvious wobble. It's not straight/centered.