Blow Gun Dart Cups 0.625" Cold Steel Big Bore Slockmaster .625

These dart cups for the 0,625" Cold Steel Big Bore blow gun are designed for 3mm steel wire. Purchasing 3mm wire and cutting them by hand is much cheaper compared to the darts made by Cold Steel.
 

The original darts have a diameter of 2,5mm but 3mm is cheaper and easier to find in Germany. It is also the diameter of the cheap bamboo sticks found on Amazon.
https://www.stahl-shop24.de/Edelstahl-Rundstab-3mm-500mm
https://www.amazon.de/dp/B00503LWEU/

The wire should be cut to 70mm or less to get similar performance as the original darts.
A 3mm wire cut to 70mm weights around 3,6g. The original darts weight 4,5g for the hunting dart and 3,6g for the training dart.

Size Options
The cups are available in different diameters. For me 15,95mm works best but this may differ for your printer setup. The difference is only a few meters per second so don't stress over it if you don't have a chronograph.

Performance Info
With 16mm I get 39m/s which is 3,2 Joules. With 15,95mm I get 40m/s which is 3,4 joules and with 15,9mm I get 39m/s again. As you can see it is not a lot of difference.
With the original training dart and original cup I get 39m/s which is 3 joules.

A 50mm wire works as well but they don't carry as much energy. I get 48m/s but due to the weight that is only 2,6 joules of energy. The downside here is that they will not stop before the cup hits the target. They strip the cup and the metal part will be stuck deep inside a soft wood stump. Still, very fast and flat shooting.

You can also use a bamboo stick which I can get to around 52m/s but at 1,6 grams it is only 2,1 joules. Super fast and very flat shooting but a little bit of wind will blow them off target.
 

Important print settings:
These cups must be printed in TPU or a similar flexible filament and you need to increase your extrusion width since the cup is only one shell thick. For my Prusa Mini with a 0,4mm nozzle I use 0,65mm for the default extrusion width.