There are ways to end up with a very high quality form 1 can. But unless you own or have access to the machine tools to make the parts, it's not gonna save you any money, just much faster from file to (no) bang.
The majority of the backlog I have right now is recoring of Form 1 cans, with a few production ones in the mix and some other projects. I think I have about 40 recores in the queue right now, most of which are Form 1 critters that were solvent traps converted by the F1 builder. Some have internals, some don't, just a tube with a mount and a front cap the maker (person/trustee on the F1) has bored large enough to pass bullets of the listed caliber. That operation, the boring of the front cap to pass bullets, is the operation which converts an unregulated item like a solvent trap or filter into a silencer. ATF doesn't care about efficacy or what's inside, so don't ever make a "sort-of" silencer by having a tube with a bored front cap that isn't registered, because that
will be considered a silencer even if it doesn't do much and doesn't have any guts.
Anyway, from there, service of the completed suppressor can consist of just about anything as long as length and caliber are not changed, and the original primary tube is not replaced.
If anyone here is interested, I can go into more detail later, but right now I have to get to work with some of the aforementioned recores.
Do these "Chinese fuel filters" actually work? If so could you file for a form 1 and use one of these?
The short answer is yes, for rimfire, and if you know what you're doing. I did a bit of experimentation with them, as I was getting them for $9/ea before customs started seizing them wholesale.
https://www.ar15.com/forums/Armory/The-cheap-chinese-can-experiment/55-502440/
Pass on any of the monocore type, and don't even consider them for anything other than .22 LR if you actually want performance.
Also, some people have had ATF calls, visits & confiscations wtih these. I don't know much about the details of which traps ordered from which sellers prompted the contact, though.
I am planning to do a review of his cans once I get all the ones I have ordered from him. It should be around the end of the year if everything goes smoothly.
The Phoenix IXs should be out of jail any day now, shouldn't they? It's been nearly a year if memory serves.