02 November 2022
Proper weight sorting the bullets will help eliminate flyers.
However, I suspect an ignition problem exacerbated by the use of LP primers, powder position and, perhaps, the psi is at the bottom end for 4227 to burn efficiently.
I suggest, as RicinYakima suggests, tap the case with the bullet up (I tap on the bench) the twist/roll the case slightly between the fingers then with the bullet up as much as possible insert the case base into the action against the bolt face and lay it down on the follower. If a push feed leave it laying there, if a CRF action gently push the cartridge into the magazine. Gently close the bolt. This is the procedure I use with my match bolt guns when no filler is used. Using measurements of velocity and pressure plus accuracy on target this method has proven to give the best results.
You might also try a bit more 4227 if the LPs is what you must use.
Additionally, I suggest drilling out the flash holes with a # 30 or #28 drill at the largest, that will allow the flash to get into the case faster and more uniformly. Extensive testing with full power jacketed loads in the 308W has proven it does not raise pressure in or out of the primer and is not dangerous. With reduced loads this also most often reduces the es and SD and improves accuracy.
Concealment is not cover.........