A Minor Improvement Over Rubberized Slugs

AMIORS are the latest development in my ongoing quest to have safe, hopperable, darts.  AMIORS contain no metal, and in fact no rigid components.  The weight is made from a nonhardening putty for use in weatherstripping, and a self-adhesive felt pad is used to provide a soft and slippery surface to improve hopper feed. 

Parts can be found at McMaster

Felt Pads:  MC # 8771K12 (green),  8771K22 (white)

Putty:  MC # 9408T14,  9408T17

So, get some non-hardening, adhesive putty:

Cut a short length of foam (30mm shown), and drill a centered hole 1/4" diameter, 3/8" deep.  The exact dimensions are not critical, and there are a wide variety of ways one can make such holes.  My most recent technique is this jig:

My most recent technique is this jig, which is a 1/2" thread x 1/2" socket coupler with a piece of partly bored out sch80 x 1/2" PVC in it (the wide bore is for clearance).  The piece of sch80 x 1/2" PVC is exceptionally loose, so I inserted some 17/32" brass for a tighter, more accurate fit.  The 1/2" pipe thread imperfectly mates with the dremel thread (Mine is a model 395, pictured is Ryan's model 4000--The jig fits on both, so presumably they are the same thread).  Inside the dremel is a 1/4" round tipped sanding bit, which at high speed makes very nice holes without grabbing the foam.  To get well centered holes it's necessary to push, bend, twist, etc on the jig until you get it right. 

After making this, I did recall seeing something similar, so I'm not sure that I actually invented this trick.  I was pretty much the last person on earth to figure out that dremels are good for drilling holes in foam.

Pull off a lump of putty, and roll it into a size and shape that approximately fits your hole.

Mash the putty in the hole.  Feel free to tear off or add putty to fill the hole, but the latter process is much easier.  The hole should be tightly packed, but not so much as to threaten to tear the foam or severely deform it.

Apply a felt disc to the top of the dart.  The adhesive should initially stick to both the foam and the putty.

And you're done!

These seem reasonably durable compared to slugs, but not so durable as their rubberized cousins, the PANS.  Since the putty is not elastic, these are much less likely to survive being stepped on or otherwise crushed.   However, many crushed darts will be recoverable by squishing the dart in the perpendicular direction to the crush,  creating an ugly but fireable dart.

At the only war these have been used in, ~600 were used, with about a dozen known breakages.  They fired reliably from conventionally hoppered springers, albeit with a bit less range and accuracy than a slug.  Hoppered HAMPS have some issues with these darts, whose cause has yet to be determined.