I use tube silicone in studio for mold making, sometimes by the case. When I cut the tip off a tube, I throw it into the box. If there is silicone left in the tube, I stick that cut off tip point first back into the tube to seal it. Not my idea but is cheap works pretty well.
Have that problem with boat caulk. Will have to try it. The video also proves that one cannot handle caulk of any kind without getting it on ones fingers and hands...
If you wet your hand/fingers with soapy water, it doesnít stick to you. Plain water works ok, but water mixed slippery with dish detergent or naphtha soap is what I use. As long as your skin is wet with this, you can almost handle it like clay or play dough. That how I press silicone into place over clay to make a silicone mold.
Video of the process, skip to about 15:50- https://www.youtube.com/watch?v=2_eBxcPIzCY