Reading all the replies is informative. I appreciate the input.
I have not bought brass yet. Honestly I think it would be wise to see how this contraption is going to shoot before I invest a hundred or two in brass. This was a free barrel blank of unknown origin that sat in a pile on a shop floor of half a dozen or so left-overs from a production run several years ago, by a guy I know. I think I will probably start off with some PPU or other inexpensive factory ammo and test with that and if the results are promising then get a quantity of good brass to develop loads for next spring/summer.
I read on another forum someone was saying Winchester brass has a high loss rate when fire forming to AI. I wonder if that's just one guy's experience or a common thing.
The reamer situation is mildly frustrating. Keep in mind this started as a low cost “fun” winter project.
I wanted to rent a reamer from “a guy.”. His website says essentially, we don't have every size pilot available. You can request a specific size, if we don't have it we'll ship out your order and when you return it we'll refund the amount for the pilot we didn't have (but of course not the reamer rental, gauges, insurance, shipping, etc).
I need a .2177-.2178 pilot, which I think is the smallest commonly available. Nothing larger will work, there's no other options. I email and ask, do you have that pilot? He replies, all your questions can be answered by reading our website. Well, in this case no. I try to explain why I'm asking, I get a short reply “there's a special request box.”
I think you can see, I don't want to just go ahead and order and see if I can use it or not when it arrives. I don't want to pay for something I can't use. But he can't answer my question. OK, no problem. We are all very busy and short on help so I'll move on. I go to another rental website. This place has a fixed pilot reamer and it says the pilot is .2177. I look at their reamer schematic. There, it says the pilot is .2190. I email and ask for clarification. Over a week now and no reply.
I guess the way forward is to buy a custom pilot bushing, wait the six to eight weeks for it, and then when it's in hand order my reamer. Just between us friends here...I attempted to make a pilot bushing. I got the ID and OD spot-on but I have about 4 or 5 tenths out of concentric. I can take another stab at it but that might be the limit of my capability
Whining...maybe. All of that to say it might be a while before I have results to report. Thanks again for all the input it is quite informative.
...and I'll add...I have the barrel profiled, threaded, polished to 320 grit, just waiting for a chamber, crowning and bluing. At this point I may simply chamber it SAMMI .223. Or .222. Not that I need another of either, especially not a 1:9, but that might be the easy button.