I recently converted my Royale's 500cc tank into a take along buddy bottle to top off out in the field after I replaced it with a CF bottle. The valve that I put on it was from Best Fittings UK which had a push button pressure relief that released the air really hard and fast. I found the correct fitting and added my own inline bleed valve that I could control the the pressure relief in a much more controlled method. I also added a longer, smaller ID micro-bore hose to get away from the gun a little further. Just in case anyone is interested.
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