Tripwire alarms

Originally published at Notes From The Bunker. You can comment here or there.

http://minisentryalarm.wordpress.com/

This landed in my email the other day: http://minisentryalarm.wordpress.com/

I actually built something very similar a few years back out of plumbing parts from Home Depot. Difference was, instead of using a nailgun blank, mine used a shotgun primer….to ignite cannon fuse.

Years ago a fella had a couple options for this sort of thing ‘artillery simulators’ or ‘boobytrap simulators’ were available from some of the usual mil-surp sources and they were ten shades of cool. They havent been offered in many years. For a number of years, outfits like CTD, Sportsmans Guide, BQ, etc, etc, offered a trip-wire system that would let off a 12 ga. blank. (Homemade version here) Those were great but I guess some folks modified them into ‘trap guns’ or somesuch and they disappeared from the matket, only to be replaced with a Nerfed-down version that uses a cyalume lightstick instead of a 12 ga. blank. Lame.

If you hunt around a bit, you can find some slightly different designs ( 1, 2, 3 ) being offered.

These arent new ideas…about a hundred years ago there used to be cool little devices called ‘trap guns’. They were nothing more that short barrels affixed to an ation and the trigger was usually a long rod with some food attached. Youd nail one of these things to a tree and when a critter came and niggled on the food, the trigger would be activated and the gun would go off…shooting the animal in the head. Sort of a ‘fishing yo-yo’ for mammals. Of course, there was always the chance you’d wind up shooting a neighbors stock or pet.

The designs eventually led to ‘sentry guns’ or ‘burglar guns’ that were a similar design and meant to be affixed to a window or door. When the window or door was opened, it would trip the action and a small (usually .22 or .32) blank would go off. Most of these were big in the pre-War era of the 1920′s or so. They turn up as novelties at gun shows from time to time.

If I had a chunk o’ property and I wanted a fairly maintenance-free warning system I’d probably get something similar to the 12 ga. systems, but scale it up to 26.5mm, and a length of tubing to act as a barrel, and make sure I have a clear shot through the tree camopy and use 26.5mm flares. Illumination and warning at the same time…nothing makes folks freeze in their tracks like that popping noise and suddenly finding your stealthy ninja-approach illuminated in that ghostly flicker of a parachute flare.

Probably in about ten years even this stuff’ll be obsolete. We’ll have tiny copters the size of a deck of playing cards that will patrol our perimeters giving live-feed video. Or they’ll just have a few grams of explosive on board and a kamikaze subroutine when an intruder is detected. Seriously. You know someone somewhere is developing one of these things in their garage right now.

 

Mirrors

Originally published at Notes From The Bunker. You can comment here or there.

Man, I’ve been busy lately. It’s just non-stop work, work, work lately. These sorts of episodes of high-demand don’t happen very often (thankfully) but when they do you have to strike while the iron is hot. So..this is why I haven’t been around much lately. however, that doesnt mean that there arent things going on…….

I picked up one of these the other day to go along with the marker panel from the same outfit. It’s made of glass (albeit thick glass) so it may not be as unbreakable as other signal mirrors out there but its hard to beat the reflectivity of a good glass mirror. I’d been shopping around for a signal mirror to put in my little survival kit for when Im hunting/fishing and I just wasnt finding anything that I really thought was any good. I picked up a few of the non-glass mirrors from countycomm and while they would probably do the job, I have a hard time finding anything thats as good as old-fashioned breakable glass.

I need to do some empirical research and see just how visible these mirror flashes are at a distance. next time the wife takes the dog for a run up the nearby mountain I’ll have her call me from the top and tell me if she can spot the flashes from up there. I would imagine reflected sunlight must be rather highly visible at range since the military used to use heliographs for communications.