I'm not a chemist,and I have never considered or attempted making primers.
Which means I mostly don't know what I'm talking about.
Here are some things that would bother me about it. Primer compound,unlike smokeless propellant,is a true explosive.
Its sort of the difference between "Whack" and "Whoosh".
Smokeless burns. Priming compound explodes. I can light a pound of smokeless,step back 10 feet and watch it burn.
Ignite a pound of priming compound and they may be scraping your flesh off the cedar fence,
Add to that its PRIMING compound, so friction,shock,sparks, etc can lead to disaster. Think walking on dust on the floor. Or vacuuming.
My very limited experimentation with "cool stuff" in my youth convinced me improvised explosives are unpredictable,dangerous,and can very quickly leave you with injuries not so different than our troops receive from Improvised Explosive Devices. You know,like a face gone or a hand gone,burned away flesh, eyes gone..... That stuff.
If its about being able to shoot without ammo or components, consider a flintlock.
One more thing to think about. Do you notice how anything you do on a computer is analyzed for marketing,ads, "algorithms" etc? Kinda creepy.
Do you suppose the Bureau of Alcohol,Tobacco, Firearms and EXPLOSIVES might track and gather up data on a person doing on line explosive research,then buying components for priming compound?
What might a pressure cooker full of priming compound do in a crowd?
The BATFE has to ask questions like that. They'd be interested in someone making priming compound if they weren't CCI ,Winchester,etc.