projectile testing - any volunteers?

[dewey-1]

Here is a 6 fin variation with thinner fins.
The CP shifts dramatically with extra fins.
The M829 has 6 fins so why not yours.

[Ragnarok]

What I have are masonry nails, I'm not sure the Ramsets are especially harder...

Masonry nails are as hard as you're likely to need.

A misguided attempt to cut one with a hacksaw (which I've used on inch thick mild steel rod successfully) resulted in a very blunt hacksaw and a very shallow cut.

In future, a task reserved for the carbide cutting disks for my Dremel.

[jackssmirkingrevenge]

Who needs a social life when you've got a lathe, eh ?

I'm tempted to agree but grudgingly acknowledge the need for some human contact, as posted elsewhere:

last night I had been planning on having a go at machining the pen gun body but my friends were having a drink nearby and I forced myself to join them, otherwise I am on the road to becoming the guy who sits on a bench shouting at passing busses before the age of 65

*ahem*

Here is a 6 fin variation with thinner fins.
The CP shifts dramatically with extra fins.
The M829 has 6 fins so why not yours.

Certainly would be better supported in the barrel too, it's under a lot of stress with pressure behind it...

A misguided attempt to cut one with a hacksaw (which I've used on inch thick mild steel rod successfully) resulted in a very blunt hacksaw and a very shallow cut.

I learnt that was useless a long time ago what I'm doing now is cutting a groove with one of my less favourite carbide tools, then clamping it in the vice and knocking the head off with a hammer - they tend to be as brittle as they are hard.

[ramses]

JSR, you seem to have duplicated my results.

[jackssmirkingrevenge]

JSR, you seem to have duplicated my results.

Thanks for that, I knew I had seen similar deformation on a nail but couldn't remember where Getting older...

Admittedly although this was from a 20x hybrid, it was also a short 12" barrel and just 19mL chamber volume. Going bigger would be more power than I can justify in urban surroundings.

Really want to try out the "ramset" layout though, perhaps this weekend.