Well i believe both plugs are equally reliable if you create a little chamber in the mouth of the standard plug when you install the vent liner. Both plugs have been tested for reliability after spending all night out with a Blackhorn load at -15°.
The CVA 209 plug works good.
The BH209 plug has a very very short flame channel. This makes installing a vent liner kinda iffy, but take some care, and i believe you can do it. The powder chamber in 209 plug is very deep. Installing the vent liner in the standard plug, one only need make the head of the vent liner about 3/8" deep, the powder chamber is then 3/8" deep, and Blackhorn powder will boom with any primer, at cold cold temperatures. The flame channel in a plug modified this way will be near twice as long, as the 209 plug.
Yes, i believe both plugs are equally reliable. The modified standard plug should absorb pressure better, and should allow more shots before cleaning??
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