Seriously, watch your shit on the 550. Talk to any reputable gunsmith (yeah that's an oxymoron- kinda like an "honest" horse trader), and they will tell you the number one source of double charge kaboom's is the lack of auto indexing on the 550.
If you can, I'd dump the 550 and grab a 650. I'd even take a hornaday over a 550.
I am pretty fond of my face and would like to keep it, so I will watch carefully. With that said, the manual operation of the 550 was actually one of the reasons I got it. I like learning about things from the bottom up. Next upgrade will probably be a ROBOT DRIVE 1050.
Buy some clean brass, hoard it in a fit of reloading decision paralysis, then switch to a less mentally strenuous hobby.
This is a good idea, but fun fact: If you give them magnets and celebrate when oddball rounds are found, getting your relatives to help you sort 58 lbs of range pickup brass can be a fun Thanksgiving activity! So now I'm committed to the Goat's Ass Brass plan.
Clean brass just to get rid of mud/rocks/grit. That's all that is necessary.
The 550 is just fine. I loaded thousands and thousands of rounds on mine with no issues.
The trick is to get a light and look into each case to check powder level. The second trick is: don't try to catch up a case if it is has a problem.
For example, you are running 9mm and you size a case and when you seat the primer you realize the primer pocket is crimped and the primer won't seat. Set the case aside and and advance the shellholder. Advance the empty space on the shellholder all the way around. If you put another case in the space you will double charge the case that you just charged when the new case is resized.
The last trick is to make sure you make the full handle stroke on the press.
That said, I upgraded last year to a 650 with bullet and case feeders. Much more expensive but much faster.
Loaded a few rounds tonight. 115 gr Hornady FMJ-RN over 3.9 gr of VV N320 loaded to COAL of 1.145" (+/- 0.005", apparently my stroke needs some work.)
The neat thing about this load is I don't think I could get a double charge in a 9mm without packing it and also it's from published manufacturer data so I probably will still have a face, but I still looked at each one and weighed a bunch of drops before I started.
The full stroke down and up I learned when the shellplate wouldn't advance because my primers weren't, technically speaking, seated.
The part about not catching up, I didn't do, because I am kind of a retard and didn't look closely enough at the fact that the powder drop actually contacts the shellplate and therefore prevents powder from spilling every which way if you don't have a case in there. But now that I have read this post and verified for myself that that was dumb, I will do so in future.
Finally, at the end of the process, I weighed the rounds I made... and half of them were 10 grains (no, that is not a typo) more than the other half, which would not be a double charge but closer to a quadruple one. I might have peed myself a little, especially since I was using all the same headstamp from my once-fired Freedom ammo. Upon further investigation, it turns out that the weight of the Freedom 9mm cases varies by 10 grains. Like, literally, half of the empty cases weigh in at 10 grains more than the other half. Thanks, guys.