New to reloading

[Griffoneur]

To answer your question of "How often to case-trim":
Case-trim as needed! The "hotter" the load, the more often you will have to case trim.
After re-sizing, use the LEE resizer, if the case is the right length, it will not remove any material from the neck. If it shaves some brass from the neck, its because its too long and needed to be trimmed. I reload my 300 Win Mag down to .308
In keeping the load low, I hardly ever have to trim.
Oh, and I suggest getting a DIGITAL VERNIER/CALIPER.

 

[rmkm70]

as suggested by some, a caliper is a must have item.
measure your case lenght, don't eye it up.
don't crimp your bullets unless your using a semi auto or lever with a tube magazine.
if your still having trouble find a local that reloads to show you the steps.