I recently bought an Ed Rayl barrel, don't recall from whom. Barrel is well made like the rest of my Rayl barrels, but came w/ the breech plug installed. I've done everything I can think of to unscrew the plug, short of unrepairable marring, but it would not budge. I would suggest asking that the breechplug not be installed.
My other Rayl barrels had a slightly tapered plug which can be difficult but not impossible to work with if you want to shorten the barrel at the breech (plug as it was too long for the pistol style).