Yes, those plugs may very well leak, because they won't be able to make a good seal with the barrel. Those tiny tiny dings on the rim, will allow blow by. Here is my opinion from a few days ago....
Originally Posted by
ronlaughlin
.......the CVA plug is too fragile to suit me. Wife goes through special pains when she prepares the QRBP for return mail, so for to protect the thin rim on the end. A couple of the QRBP folks have mailed, have arrived here damaged........