I have not been able to try the spark plug this afternoon, the remote control batteries were empty ...
sorry ...

I had 4 shots!
there are good things!

Nice shot! yes I covered tungsten by copper tubing 6/8mm. For the tungsten will not fragment on. The first tip is a tip of arrow arc stainless steel, it is small, 4mm in diameter and 46mm in length. the black circles, it's tap rubber roller. For the big stainless steel spike, it is free in the alumi...

Yes, I tapped at M10x1mm and spark plug is screwed on 10mm
Thread lock is sealed (Loctite 243)
This afternoon I'll do a shooting test

Spark plugs with new motorcycle M10x1mm, the spark plug gap is 7/100

this is glass!
I'll keep using carbide ...
The fin brass looks good!

This afternoon I fire!
I prepared new projectiles

Great!
thank you!

For the pusher plate I can use plastic rods or rubber roller for valves.
it is certain that mold would be more accurate

dimensions of nails:
Smooth diameter: 3.4mm
Striated diameter: 3.5mm

It would be such a great mold

I have much of epoxy because I'm stratification carbon and kevlar for my water rockets

replace the delrin glue on a concrete example nail dart

or a mold with the shape of your APFSDS where I can put a tungsten rod ...

I will try to make a mold of a spoiler delrin that thou hast made​​.
I can then pour it hot glue for example

Et un peu le ThorJack aussi !

I doubted that it was this hybrid!

I think too!
and you're going to shoot with any gun ?

Profile is good too ... when there is no dust!