ive been shooting a k hornet (have4) for 30 years and have always come back to 296 always.have you slugged the bore could be 223 and while you are at it check the twist as well. The winchester ammo is 296 should be easy to check with a mag glass.when i say we shoot alot i mean 2000 just hornets in a week gopher hunting as well as cases of 223.my load all guns 35 hornady b tip 12.5 w 296 small rifle Mag primer and play with seating depth tip short works. Watch your cleaning 3 of my hornets hate a really clean bore and it takes 20 rounds to get them to behave even after hundreds of shots i only swab with hoppes#9 and a dry patch.I would work on a 35 or 40 b tip load again play with fouled barrel and oal the btips explode a gopher 46s in a non k hornet dont i know from vast field testing. hope this helps ps need 6-06 loading data any ideas?