300 win mag reloading

Bought a used rifle from a friend. It’s still being held ransom by my state for 10 days. So I can’t fully start reloading yet. It’s a 300 win mag and came with 35 pieces of win brass and 70 pieces of rem brass. I neck sized (lee collet) and got the same neck dia for both dummy rounds (.335). Both were also .333 after the collet and about .341 before. One was a little out of round and took 4 passes vs 2 passes in the die. I have a Hornady bushing die so I’m guessing that a .332 bushing would be best to start with. My plan is to neck size until the brass won’t chamber then to bump size with the full length bushing die. Thought it was interesting that both brands had the same neck thickness. Comments on my plans?

Also planning to start with H4895 and reduce loads to make shooting more enjoyable unless I decide to get a brake. This is a hunting rifle though. Any tips on reduced loads for practice? I have 155gr and 175gr Nosler CC to start with from another rifle so I’ll start there. How many of you use regular LR primers for the reduced loads vs Mag primers? I just want to get proficient out to 500 yds. That’s the point where velocity loss will cause most of my state mandated bullets stop deforming and pencil through game. Plus I don’t want to put the time into being proficient on game in field conditions and unknown ranges past that distance anyway.

Interestingly enough the Hornady factory ammo I bought had a .335 neck OD as well. So .332 looks like a good bushing for me to have. Not that I’ll have Hornady brass unless I get a bear or elk tag next season. It’s 165 GMX superperformance so a little overkill for deer. My goal is to push the slightly higher BC 150 gr etip a little faster for a longer MPBR and fewer calculations for shots beyond that. Think I’ll use the lower qty of win brass for that project so I can load them all up once I reach my goal.