The standard pierce-pin seal, JB Welded in place, has never blown out on me.
I've tested it in game, on and off field and with 12-grams ranging from nearly empty to full.
Advantage to the standard CCI seal is ease of availability. Everyone can JB Weld a seal in place.
Disadvantages:
- If a full or near full 12-gram is dumped into the seal, it will frost up enough to require warming prior to installing a new 12-gram.
- NOT letting it defrost will result in an unstoppable leak: the fresh 12-gram will start by leaking slowly, contributing to the frost problem and making the leak worse until the 12-gram is empty.
As an aside: you can modify your velocity adjust tool for use in changing pierce-pin assemblies. See this thread:
http://www.mcarterbrown.com/forums/c...-assembly.html