saw these screws on a gunbroker auction.....
What do you think ?
Know of any commercial sources for these ?
For some reason your link didn't work but if these are the grade 8 black allen head screw kits you're talking about, yes, I've seen them.
We have a store here called "Truck & Trailer" that carries all sorts of grade 8 bolts and screws, and I have seen similar metric allen head "button" screws like this.
Apart from not having long enough screws for the rear trunion the screws themselves look pretty good, and offer a viable alternate to riveting or welding. Tapping and screwing on the receiver does have one benefit if you ask me, and that's ease of disassembly if for any reason you find yourself needing to take apart your rifle for any reason. Of course I would use Red loctite with these if I were to use them, so heat would still be needed for disassemly, but the receiver itself can be saved.
An Alternate to the Loctite would be to tack weld each screw to the receiver after it's torqued down properly. This would offere a more permanant solution but without the need of a press like rivets.
They also look kinda cool to me, giving the gun a more "mechanical" look to it, but that's just my opinion. Imay give these a try on a fututre build.