Yeah sorry I was typing from my phone so I didn't address all the questions.
If using tape make sure you wipe the area you will be taping with a degreaser of some sort (alcohol, simple green, etc). Otherwise the tape won't stick.
Finger cots will only work if the barrel is fat enough. Most hunting rifles do not have a fat enough barrel to sufficiently stretch the latex so that it is snug fitting. So, in the end you will need something else to hold it in place.