In I think 2013, Tim McMurray at Mac 1 Airguns showed me this dual piercing end cap for a Sheridan or PMI paintball marker or pellet rifle. This was made by Sheridan as an alternative to the dual piercer style McMurray was already constructing and pierces a forward facing 12 gram (reverse to the normal style).
A quick look at this piece in the video reveals a few of it’s flaws.
1. It is one piece with the end threads. This limits the paintguns it could be used on since it would need to line up directly at the end of the tube to function.
2. It is more difficult that Tim McMurray’s model to disassembly. The model that Tim at Mac 1 made used simple Crosman parts to piercer and seal the 12 gram and a C clip retaining pin to hold it in place. Looking at the Sheridan built model I am not entirely sure how it functions. The piercer appears to be spring loaded, meaning it could be more forgiving to different lengths of 12 grams, but the path to disassembly is not entirely obvious.
3. It’s steel, so it would end up rusting. Tim’s designs was aluminum.
4. It’s a permanent piece, where Tim’s design was internal to the tube so it could be removed if the user decided to not use the dual setup.
Still a neat piece that I’ve never seen a duplicate of. Maybe, as Tim said, Sheridan made this Dual 12 gram piercer as a prototype or maybe it was made for an airgun in the past? I think it must be a prototype, because if it was made for an existing model of airgun Tim would have pointed that out.
Find another article that shows a photo of this dual piercer at:
And find Tim online at https://www.mac1airgunshop.com/
And helpful airgunning details from Mac 1 at http://www.mac1airgun.com/