Went shooting with my buds today & noticed that my BM did very poorly. I have shot about 2K rounds out of it with very good accuracy but today none of us could hit a barn with it. Its a BM shorty with AK break on it. We were shooting from 100yds with peep sights. Wolf ammo....I shot Wolf ammo out of the Colt Match Grade 20inch that was there also & it did fine...10 ring every time. I've seen my BM shoot just as well in the past but today it sucked.
The BM seemed to vary quite a bit in where it would shoot...all over that darned target. We were shooting from bench rests.
Any suggestions (other than get a Colt Match Grade)?
It sounds as if you have an extremely copper fouled barrel. Try using allowing a liberal dose of Sweet's or Hoppes copper fouling solvent to work in you barrel for a few hours before a good scrub with a nylon .22 cal bore brush.
Usually when your accuracy goes to he11 after a few thousand rounds it's due to copper fouling. Sure, you can "clean" it (read: Remove the carbon.), but with a .223 you need to remove the copper fouling as well.