Hey fellas,
I never caught this thread before now but it's a good one and a good test by Gil. We use monofilament almost like the one he described, slightly larger 400lb 2.0, swaged with 2.2 double barrel Nickle or black treated copper crimps/sleeves.
I just wanted to add a couple things that can also make the difference between failure and non failure from my use and experience with mono over the last ten years on spearguns and fishing rods:
Black finish copper sleeves or nickel that match the mono being used (same brands) will always ensure a good connection since that's what the fishing manufacturers test their own mono strengths with (their own crimps or mono and vice versa). Use 2.2 crimps with 2.0 400lb mono, 1.9 with 300, etc...(match the hatch).
Stay away from the alluminum natural colored double sleeves, for some reason we find them weaker and easier to swager than the others and the few times we've tried'em there have been some failures.
The B method Gil described is the most common and works well, remember 70% of 400lb mono is nearly 300lbs of direct force and you should never be offering such resistance anyhow while fighting any fish or a rock. The floats, stretch in the mono, or the reel line should be used to play the fish to avoid ripping or break offs. It's an old saying among pro's the "rookies have break offs, pro's have occasional pull off's" A pull-off is beyond your control some time as the spear rips out or comes out as you play the fish and the connection, a break off or failure is user error. To cut to the chase, if your equipment is properly set up and connection is solid it's up to you to know how to properly play the fish to avoid both break offs or pull off's.
Some small things a watchful eye will always check are the holes where the shooting line loop attaches to the spear-shaft, I always take care to make sure they are beveled again with a small cone file or sand paper. A sharp shaft hole will cut the mono loop clean in a second with a sudden burst of pressure or power if it's too sharp. The other thing we do on all the guns we set up is a small last pre-ship check test, attach the spear shaft barb to a solid object like a work bench and pull it steadily from where the shooting line attaches to the muzzle bungie in the front of the gun applying a hefty amount of pressure to stretch your shooting line three or four times. Since mono stretches, it's best to try to stretch it when it's new so you don't have to reset your loop length and shock bungie length after the first few uses. You're also verifying that your crimping job is solid and there are no nicks or weakpoints in your shooting line you might have overlooked.
Lastly, if you're serious about your equipment and rig your own stuff invest $30-40 in a good Swaging tool like the one Gil showed. The other one that was shaped like needle nose pliers I saw at the beginning of this thread is okay, but you can never get the same torque or replicate the crimping job the proper crimper/swager will do closing the crimps correctly and professionally. The end result between a half ass crimping job and a good one is the difference between landing or loosing a strong fish.
Good luck, Mark
