So far my best (reliable feeding, ejection and accuracy) are with 115 grain bullets. I reload hollow points and buy factory (Federal) 115 grain FMJ.
I use a very slow burning powder for my reloads. No way to double charge a case with it. It requires more powder (less loaded rounds per pound of powder) but, it's accurate as can be and the bullet isn't poking along on it's way to the target either.
Can't say there aren't several different slower burning powders that will insure you don't double charge a case while learning the right things to be vigilant about, and there could be more that will give you good groups. So far I've tried some other powders for plinking loads but nothing shoots groups like that 115 grain hollow point (Precision Delta bullets or the 115 grain hollow points from Everglades Ammo sells them).
A lot of folks here also like 124 grain hollow points for accurate loads in their CZ pistols. So far I've not found any loads for 147 grain bullets, or even factory loaded 147 grain ammo, that shoots good groups in my CZ pistols.
I don't have a scorpion. I do have a couple of AR15 9mm carbines and both shoot the 115 grain hollow point loads my CZ pistols like very well. Again, function and accuracy are what I look for.
I've got some 124's to try, just bought a different brand the other day. Just need to get them loaded up with some different powders/charge weights.
One thing to keep in mind is the chamber on many/most CZ 9MM pistols will require deeper bullet seating than some other brands. Be sure you do some "plunk" testing to find out what you can do with your pistol.
Inspection of components at steps during the reloading process, inspection of your reloading equipment/process, inspection of the loads rounds and not getting distracted while loading is very important.
I may have the same reloading set up you do. I'd recommend buying a die plate for each caliber, setting up the dies and locking them down in the plate. That eliminates any set up variances one reloading session to the next.
I don't use mine as a progressive type unit. I took all that out and just use it by manually turning the plate and doing the reloading steps in batches.
I resize a batch of brass. Could be a 100, could be 400. I inspect the brass after cleaning/before resizing. While resizing, be ready to inspect a piece of brass if anything feels or sounds different.
Then I prime that batch of brass. I might only do 100 (for a couple boxes of brass) or I might do more. Again, you can feel something that goes wrong when you're priming. Oh, I use a hand priming tool and have for so many years I don't even know where the press mounting priming stuff/parts are anymore. I look/feel the brass/primers to make sure they are correctly installed.
Then I charge the cases with powder. Some powder feeds/meters very uniformly/consistently from a good powder measure. Some won't and there's nothing you can do to the powder measure to make it work better (if you need consistency). For those powders I use an electronic powder measure/scale to get consistency. I use a small flashlight to look into each case (there's 50 of them in a tray) and make sure they have powder and are consistent in amount of powder. You'd be surprised how well you eyes/brain can see small differences in powder level in the case. If I see one that looks to have more/less powder than another I weigh the powder charge on the scale.
I weigh 1 charge from every 10 in the cases. So 5 weighed for every 50 charged. If I don't find 5 that look wrong I pick enough random one to total up the 5 I need for every 5.
Then I seat the bullets (and crimp the case mouths) a lot of people do this in two separate steps. I never had a need to do that. Again, pay attention to the way things feel and if something doesn't feel right/feels different, stop and investigate for the cause.
Keep a reloading log book. I record date, caliber, primer used, powder and amount used, bullet used, cartridge over all length, when I measure it and how many rounds I loaded. I then write all that down on a separate piece of paper and put it in the container with the loaded ammo so I know what it is and how long it's been there when I open the can/jar/bottle/jug up.
When I work up loads I choose a powder, based on what I have on hand, or what I read on the internet, and what I see in the reloading data and I start at the starting load and work up in 0.2 grain increments. Then I go to the range and try it out to see what gives me good groups and functioning.
Be careful. Be attentive to what you do, what you see and what you hear - and how it feels as you do it. Ask questions here when you need to. If you feel something is wrong, stop and start again later when you find out what was wrong (if anything) and feel you've overcome the issue and can finish while making good ammo.
You can make ammo that will shoot better in you guns than any factory ammo you can buy. I've been trying to make a new 2.0 M&P 5" 9MM shoot better. I told you the load my CZ 9mm pistols shoot so well (well, sort of, 115 grain bullets and a slow burning powder many people would never consider for 9MM loads). Shooting that ammo in the M&P is a waste of time. So I've bought Winchester, Federal and Remington factory ammo for it. In weights from 115 to 147 grain. FMJ and hollow points. The M&P did it's best (not as good as my good CZ's) with factory Winchester 124 grain FMJ (NATO) ammo. Part of testing is shooting all that ammo in a known good shooting CZ 9MM and none of it shot as well as my 115 grain hollow points or the Federal 115 grain FMJ factory ammo (that's why I buy the Federal stuff, it shoot so well in my CZ's).
Start slow, pay attention - and the final piece of advice in this post - I have never had the best groups from the maximum charge loads listed in the reloading books. Just haven't. Not with pistols or rifles. The best groups are usually 150 fps or so slower than the fastest (highest pressure) loads. Oh, the M&P may end up being an exception to that experience as the NATO ammo is usually pretty fast. I bought a different powder to use when working up the 124 grain loads for the M&P.