ellenbr,
that is an inline capper sold by many muzzleloader suppliers, sporting goods shops, etc. Another popular capper is a Ted Cash capper. Also easily found. Try www.trackofthewolf.com Put it on a string around your neck or in your pocket.

Many of the commercially available speedloaders have a notch or some similar structure for holding a percussion cap.

The taped centrifuge tubes look pretty functional however. They appear to have the screw on tops, which I found have strong advantages over snap on caps - esp. if you do a lot of elevational change.

_________
BrentD, (Professor - just for Stan)
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