lots of great input in this thread!
a very good adult discussion. congrats to all for keeping it civil!
back on the topic...
i just dont consider the x25 round a good "kids round" and dont let my kids shoot any of my x25 guns. its just WAY too hot and the loads are just crazy in their differences of power/speed. and ive built way more x25 guns than im ever gonna admit or post.
someone mentioned the chrome barrel thing, the barrel i took deeper was NOT a chrome barrel it was just a 16" regular x25 barrel from IO that we stuck in a sten build.. so taking it a hair deeper was as easy as you mentioned and then adding that extractor "notch".
im gonna use the ppsh or 43 barrel and bolts combo for exactly the reason you mentioned.... its DESIGNED to have that space and functions perfectly that way.
the bolt weights are very important, we found out early in the ppsh41 conversions and then the 43 that you had to have all that weight for a short barrel and that a little more doesnt hurt if your using the 16" barrels.
the x25 is a great caliber to play with. its dirty, loud, smoky, fiery and cheap to shoot.
just look at my P7 video and see what i mean, that is in x25 with a 16" barrel and the factory epth of chamber and bolt head depth is set by the 9mm AR bolt head. it works perfectly and runs like a raped ape....
but it is just like all the FA x25's and just kills the cases.
the cartridge was just never meant to be reloaded.