Re: Dillon 550 vs Dillon 650????
Neither the 550 or the 650, or any other model, is a "safe" press. Safety lies with the guy pulling the handle. I agree, the 650 has features that make it more forgiving, however, such devices can breed complacency.
It's been some time since I read the instruction portion of a load manual, but in the past, loaders were cautioned to check each case before seating the bullet. If we follow that simple rule there will never be an overcharged or squib load. We don't ignore stop signs just because our vehicles have airbags.
In addition to the visual rule above, three simple rules apply to a 550:
1) If you must stop before finished loading, stop with the ram at the top. That leaves no questions about when you were.
2) If you forget rule one, pull all the cases and start fresh.
3) If you ignore all of the above, sell your press and buy factory ammo.
If anyone ever loads an overcharged round, check the bathroom mirror to see who is at fault.
I have no argument against the 650; I wouldn't part with mine, but the 550 has it's place, just as single stages do.