Arent those DWV endcaps known to blow out sometimes?
Removing threads wouldnt help it.
But you could always try.
If they did, I would assume its from the outer piece flexing out and letting the threads fly out, not from the threads failing, so I would assume a tightened pipe clamp around the ...

I'd kinda like to see that on a spudgun. I'm sure it would hold okay with a combustion.
I might post pics when this gets done, which may be quite a while, as it isnt the highest priority now (all i have now, is the barrel, chamber pipe, and the ignition system, a grill igniter), and speaking of ...

probably just dremel it out. the only thing im worried about is just that the remaining thread won't be strong enough, but that might depend on what i use for propellant, too

On a breech loading spud gun, is it safe to modify the PVC screw-on endcap so that it operates as an interrupted screw breech (i.e. remove 1/2 of the thread surface area so that the breech can be inserted and turned 1/4 turn to be fastened)?
link, in case anyone doesnt understand what I mean
http ...