LOL!
Hey! I´m the little techie!
They´re guns. They´re SUPPOSED to shoot! In fact, that´s the general idea...
Threads for the nipple were shot and to the level where the correct option was to fab an insert, a weldbung. Thread is the correct 5/16-24 (UNF in other words) and that small "mismatch"/opening between the insert and the receiver isn´t a mismatch...
It´s a weld ditch.
Be adviced that the openings and details here are rather small to hit even with a TIG welder, and the idea is to use the TIG to basically merge to the materials together.
In turn, yes a fresh one is on route. However... This is a cartridge gun and at that one that lacks a built in primer. As such the opening at the bottom of the nipple needs to actually be drilled OUT in this case, seeing the design at hand.
The restriction, of backpressure, takes place at the flame hole in the actual cartridge. Ie; the cartridge opening is set to 0,8mm and thus i try and hand the passage for it, from the nipple down, all the help it can get.
So 2,5mm (0,1") it is...
In turn, need to readress the extractor. As it turns out it´s to stiff, bends the rim of the cartridges ever so slightly. Need to make it more "spongey" in short.