youngolddude
Professional
4.0 is fine. Most of my sources use exactly this weight for a starter load. Even if it dropped to 3.8 gr. it would still exit the barrel. You would have to drop to a very low charge to get a round stuck in the barrel (squib). This is no where close. Once you fire your rounds, you can always examine the primer in the fired cases. Low powered loads will not push the primer back into the case. This is very evident with a revolver, but I would think it would also happen with an automatic. Anyone, correct me if I'm wrong.
With normal reloading, a powder dispenser will stay within a tenth of a grain at most. Not enough to worry unless you are a bench rest shooter or long range shooter. I had no issues with the Lee powder discs way back when I used those machines. I had issues with the primer part of those presses. Powder can clump, so most people return unused powder to the containers. I load often enough I leave it in the hopper and stir the powder before starting. With the Lee presses I had, the dump performed quite well. The only issue that could arise on mine was if it didn't return all the way.
With normal reloading, a powder dispenser will stay within a tenth of a grain at most. Not enough to worry unless you are a bench rest shooter or long range shooter. I had no issues with the Lee powder discs way back when I used those machines. I had issues with the primer part of those presses. Powder can clump, so most people return unused powder to the containers. I load often enough I leave it in the hopper and stir the powder before starting. With the Lee presses I had, the dump performed quite well. The only issue that could arise on mine was if it didn't return all the way.