Rigging and Crimping Your Speargun Shooting Line Using an Open Muzzle

tool kit

In your MAKO Attack Pack Tool Kit you will need:

  • E) Crimping tool
  • F) Scissors
  • H) Lighter

You will also need:

Using an open muzzle on your speargun is rapidly becoming more popular particularly among blue water hunters.

  1. The shooting line holds the shaft tight to the rail, even when upside down. This allows shots to be fired from all angles including while upside down
  2. Reloading after a shot with an open muzzle is actually quicker. Because the muzzle is open, you do not need to insert the back end of the shaft through the muzzle before locking in the trigger mechanism
  3. Some spearos say sighting down the barrel is easier because the muzzle does not extend over the shaft.

open muzzle

Install the bungie (shock cord) to muzzle. Using a piece of tape, mark the barrel where the swivel meets with no tension. Then mark the tape where the swivel meets at full draw. Then measure and put a mark half way between the two marks.


Using a double barrel crimp sleeve, connect the mono to the spear or "dog house". (see basic crimping techniques)

Dog House

Insert the spear into the trigger mechanism and route the mono up the barrel towards the muzzle. Then route the mono around either the left or the right tab on top of the muzzle and then back down the barrel towards the grip, around the line release, back up the barrel and form another loop (using a 2nd double barrel crimp sleeve) that meets the 1/2 way mark you made on your barrel. Finish by attaching the newly created loop to the swivel clip on the end of the bungie.


When loading your spear using an open muzzle, simply insert the spear into the trigger mechanism. While holding the spear in place with one hand, use the other hand to route the mono up the barrel, around either the left or right tab on the top of the open muzzle, then over the shaft and back down the barrel where the mono is secured at the line release.