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Putting a drop of hot glue into the seating stem and then squidging a bullet in there to mold it to the shape of the bullet. Spreads the seating force and stops the bullet deforming so easily.

No worries. Bill999's absolutely right and I had a similar experience getting the buggers seated. Ended up buying a Lyman 30M1 expander die which helped and used the hot glue gun trick on a spare...

Hi Ash. The 300BLK case is a lot smaller than the 308 case. You won't be able to get 7.5gr of trail boss in there without compressing it (which is big no no with that powder).

From memory, 6.2gr...