New To Me Old MEC 650 Progressive 12GA. First Foray, Help!!!!!

All load data is specific as to powder shell wad and shot. It’s not a mix and match deal. I only reloaded AA for trap. Hunting loads I bought. I did buy the slug mold and roll crimp and made up some slugs. I knew a trap shooter who had a shot casting setup. It had a very little hole that lead would drip out and roll down a plate and then drop into a bucket of tide laundry soap.

I have a MEC 650 in 20 gauge, that came to me in a similar condition. The main issue with this model is that you can't resize to brass portion of the hull. If you are using one gun it probably wont be an issue. But, it's something to consider. The 600 has a resizing adapter that can be installed. But, I haven't seen one for the 650. You have had some good advice about reloading, in the past threads. One gave you MEC's website. That is the best place to start. If you haven't, clean it up as best you can. I wouldn't try to take it completely apart.(i.e. the main spring column). Get the 650 manual from there. Read it. Write down the parts, with the part numbers that you are missing. Order the missing parts from MEC, via online, or call them. MEC's customer service is as good or better than Dillon's. Your charge bars at the older models. They will work, but can be a pain. Newer versions, that take powder bushings, and have a set amount of shot would be better. Bushing charts are easy to find. Although, they usually don't drop the amount listed. It takes a little fiddling with. Here is the sad part. You can buy 12 gauge and 20 gauge cheap from Walmart(for now), or other places. If you are buying shot, it can be expensive. Most shotgun powder can be used in pistol loading, and that helps. Primers are easy. But if you use RIO primers or other imports, they can run a little large. Meaning, once you use them, you have to continue to use them. If you replace them with say Winchester, they may not seat firmly and fall out.. I have seen this. This is a heated topic, with some people. Like one of the posters said. Follow the reloading manual for the proper hull and wad column fit. Wads are cheap. That said, I love reloading. I still load for my 12 and 20. I shoot sporting clays almost every Sunday. Occasionally, I run short in my loading. I go buy some factory loads. It comes down to time. But, I will always reload for them. When you find a load that works best in your gun, you stick with it. Its why we reload.
Good luck. Read the manual. Call MEC. Be careful. Have fun.
Ed

Man I'm loving all the well written responses here. You guys are awesome! Sadly the reloader has been just sitting on my work bench for a few months not getting any love. Just been too busy to mess with it too much right now. I'm also working my way through the reloading book I got with it, figured it's probably better to have read that from cover to cover before I continue on. Once I finally pull the handle on some new reloads I'll post up the results. Might be something I tackle this winter as a side hobby more than anything.