Priest slug project

Air Force Texan, eat your heart out!
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I drilled and tapped the frame where the shroud goes through. Then I built Delrin bushings for those same areas. I am trying to trick my barrel into believing it’s only 8 inches long. It made a significant difference in group sizes. I couldn’t get a 15mm slug barrel and had to go with a 9/16. Had a piece of 15mm barrel so I built a sorta thimble to get a nice fitting barrel. About 8hrs on that project. Trying not to mess with my pellet setup. I don’t even use the same reg or bottle. If the slug thing goes south, I just want to bolt the pellet shooting setup back on and live happily ever after. It’s a crazy good gun on 25gr pellets. Just want to see if it can be my new slugger or not. 
 
Cleaning my barrel now so I figured I would take a pic of what I put in my shroud. I left one inch between the end of the barrel and the beginning of the air stripper. I also put one vent hole in shroud. The first baffle/stripper is attached to the shroud with a button head screw. Then I just load all the other stuff in and put on the end cap also with a button head screw. Very very quiet gun.
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This is what the Texan should be! I cant believe AirForce has not completely re-designed their ancient guns yet. 800 fpe is cool, but who wants to be hunting and have to dig for the next round of ammunition for a follow up shot. 

What is the length of the barrel? How many inches did you leave for the baffles? .22 or.25?

Edit: I noticed you answered my second question with your picture while I was typing my question!