[LUTNIT]

Okay, so I'm trying to swap front ends on a G&P SPR but ran into a really strange problem with threading. I'll list whats up:

-original G&P front end was put on a PTW, threading fit, also fits on TM
-cheap crappy Dragon Fire front ends fits on this G&P and a TM I have
-cheap crappy Dragon Fire front end does NOT fit on a PTW
-DBoys SPR front end fits on a TM but NOT the G&P

So G&P barrel nut fits on G&P, PTW (real steel), and TM.
Barrel nut that fits on G&P and TM will not fit on PTW.
Barrel nut that fits onto TM will not fit onto G&P.

All three of these statements seem to contradict each other. Does G&P somehow have dual threading or something? I thought maybe it was just really stiff so I put some more force on it with a barrel wrench and it stripped the first threading inside the DBoys barrel nut. I tried forcing the Dragon Fire barrel nut on a PTW with a wrench as well but it kept going on skewed, if I forced it straight it started to eat threading.

Any ideas or experience? Do King Arms or Madbull barrel nuts fit on G&P bodies?