Disposable Powerheards
Hi there,
I have been using disposable powerheads for many years now and actualy manufacture my own. You just need to know somebody with a metal lathe or if you have a good engineering firm close by that can do the job for you it also helps. I basically use a piece of aluminium tubing and get it drilled open so a .38 bullet can just slip in, but with a shoulder inside to catch the edge of the bullets casing so it does not slip through. Be carefull not to make the shoulder too deep otherwise the nose of the bullet will stick out on the other side and you will get a misfire when it hits the shark. Once I have placed the bullet inside I just use a piece of plastic pipe or tubing to secure the catridge inside and wich fits snugly over the tip of my spear, so the spear tip acts as the trigger. As a final touch you can seal the catridge with wax. Your powerhead is now ready to be used either by firing the spear or just bumping a shark.
I have only used a power head once (with remarkable success), but it is not something I would like to do again. a Word of caution , powerheads are extremely dangerous and if you should fire at a solid object your spear will come straight back at you!:naughty
Hope this helps, if you need a sketch, mail me and I can fax it to you.