Give UC a try to see if he has advise. If you want you could always email Dan at
bullshop@wildak.net
He might be willing to send you a sample of different diameters to try in your barrel. That way you are sure you are getting what you want when you order. He does a great job and even with shipping from AK, they are very economical. Pretty sure the shipping is the same on orders up to about 500 bullets. If you get a sample and find the one you like and place a big order, it will come out to about 22 or 23 cents each.
Your postman might ask you, "What is in that box, lead?" You just say, "Yup."