.250 Slugs n the Flashpup

Trying some .250 that I won this time, and I need to fix my Flashpup, it's dropped in power. I had a few shots without a slug from one of my mags not cycling well with the slugs. I changed the breech seal and tested it today, it's still not up to speed. I guess I need to peep in the port to see if there's an issue. I have a rebuild kit, it's probably about time to refresh all the seals in the gun, to be honest, but if I could get by with a breech seal I would.

https://youtu.be/0VXIw7_UvBw
 
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