Kody; I think the sales person gave you wrong information about the Super UNI Bushings. Take for example, a 2016 arrow means this: The 20 means the dia. of the arrow is 20/64 dia.. The 16 means the thickness of the metal 16/1000th inch thick. These numbers have nothing to do with the UNI BUSHING itself. This information is in any Easton archery arrow selection guide. Easton is the company that makes these bushing's. You are correct about the different bushing sizes, such as 2013,2014,2016,2018. As you can see the only thing that changes is the inside dia. of the arrow which means you use a thicker or thinner Super UNI Bushing. The numbers have nothing to do with the rim thickness because---the rim doesn't go inside the arrow. The bushing stops going inside the arrow--at the rim. The rim just prevents it from going down inside the arrow. There are two more I think I should tell you. 1. Now Iam talking about the bushing its self, so we can forget about arrow sizes for now. The inside dia. of the bushing,( where the plastic nock would fit that would hold the arrow on the bow sting) never changes. That's the hole where you would place your 209 primer. So there's no adjustinng for primer size in this hole. 2. This is the bad news.--This will not work on your Hubbard breach plug. Its designed for a 209 primer already. This uni bushing idea works only with the 25acp breach plug only. What Iam about to say is only my 2 cents worth of understanding about a Hubbard plug. It sounds like they made the primer hole to deep and that lets the blow back come around the primer and into the action. It sounds like its not the dia. of the primer hole( I've seen where it looks to lose to do any good) its the depth of the primer hole. I'll suggest one more trick you could try. Here goes-- take some teflon tape and wrap the powder side of your breach (maybe two or three wraps) and I think the thickness of the tape might move your breach plug and primer back closer to the frame thus keeping the primer more snug. It might have the effect as having a longer primer. Folks use tape to keep the blow back from coming back into the threads and making a mess with tripple7 powder. It might not take but a small amount of moving the breach plug toward the frame to turn this hubbard plug into a real jewel to own. Your very fortunate to have it.Kody I can't think of any think else I could tell you to help. Keep at it and don't give up. Jenks