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Posted: Sun Apr 15, 2012 2:51 pm
by Petitlu
I'll have to shoot to 90 ° from the target so that the dart arrived straight ...

Posted: Sat Jun 02, 2012 11:11 am
by jackssmirkingrevenge
Monitor burned out at work, hence shooting video :D

[youtube][/youtube]

Posted: Sat Jun 02, 2012 1:20 pm
by Labtecpower
nice :D

mix, projectile, launcher? :)

Posted: Sun Jun 03, 2012 1:08 am
by jackssmirkingrevenge
Labtecpower wrote:mix
15
projectile
12g CO<sub>2</sub> capsules cut in half and weighted with lead'n'epoxy :D
launcher?
The subject of this thread, in this case with a 42mL chamber and 75cm barrel.

Posted: Tue Mar 05, 2013 6:43 pm
by jackssmirkingrevenge
The joys of testing in your workshop, things from the past keep turning up :D

More than a couple of months ago I had fired a steel core from a 7.62 AK round at a steel plate, it zinged off and never found it... until today! Here it is next to a relatively intact example:

Posted: Tue Jul 02, 2013 7:13 am
by mako
Hey, JSR, got a bit of a tip for you.

You said earlier in the thread that the projectile merely deformed. As you also stated, it was a piece of mild steel.

I don't know if you know anything about carbon percentage or tempering, but you should look up blacksmithing. You could probably use high carbon tool steel for a projectile, shape it, and then harden it. That would make it much less likely to deform, and you could fine tune the temper to get the best results.
(amateur blacksmith experience speaking here)

Posted: Tue Jul 02, 2013 7:23 am
by jackssmirkingrevenge
mako wrote:You said earlier in the thread that the projectile merely deformed? What type of steel did you use? What was the temper on it?
Some alloy I pulled out of a printer cartridge, really nothing suitable. I didn't heat treat it in any way.
I don't know if you know anything about carbon percentage or tempering, but you should look up blacksmithing. You could probably use high carbon tool steel for a projectile, shape it, and then harden it. That would make it much less likely to deform, and you could fine tune the temper to get the best results.
(amateur blacksmith experience speaking here)
I wish I had the time to play, and some sort of forge... maybe once I'm across the Atlantic :)

As it is I just ordered these HSS blanks off eBay, I'll grind a point on them and hope for the best :D

Image

Posted: Tue Jul 02, 2013 7:29 am
by mako
Well, even grinding can change the temper, so take it slow.
Also, if you have even a hand-propane torch you can harden. Just heat the part that you want hard to at least a dull-red heat(ie, you can just see the glow if you are in a dark room) and then quench in water or oil. Oil makes it slightly softer. That process will make it as hard as it can get.
If you want the tempering process too, you'll have to look it up else where. Its too early in the morning for me to think about it much. :D

Posted: Tue Jul 02, 2013 7:39 am
by jackssmirkingrevenge
mako wrote: Also, if you have even a hand-propane torch you can harden. Just heat the part that you want hard to at least a dull-red heat(ie, you can just see the glow if you are in a dark room) and then quench in water or oil. Oil makes it slightly softer. That process will make it as hard as it can get.
That sounds very doable, will try some tempered and some plain.

Posted: Tue Jul 02, 2013 4:42 pm
by jakethebeast
Dull red? whoa there... Depends on the lightning, material, quenching solution... At my shop the perfect color for my blades is orange color. And yes, i have tested this with proper temperature meter.

And my shop has few flurocent lights so its nothing but dark

Well, atleast my old shop did, i really need to take you a pic of my new monster forge..

Posted: Tue Jul 02, 2013 6:00 pm
by mako
I agree with you, Jake, but dull red DOES work, and as a rule of thumb it works pretty well, especially if all you have to work with is a propane torch.

Posted: Wed Jul 03, 2013 12:36 am
by jakethebeast
When i started making blades people told me that too but i never succeeded with it :D

Posted: Wed Jul 03, 2013 9:28 am
by mako
You DO have to remember that making a nice temper on a beautiful handmade knife is way more demanding than hardening a piece of steel you are using as a projectile. If you just want to harden it up to prevent deformation, the torch will work just fine.

(trust me on that one) :shock:

Posted: Mon Jul 08, 2013 1:55 pm
by jackssmirkingrevenge
[youtube][/youtube]

This promises well :)

Projectile was the bottom one fromthis group.

Posted: Sun Jul 14, 2013 7:15 am
by jackssmirkingrevenge
I decided to have another go at my nemesis, the hardened 1/4" plate.

Didn't quite go as planned, as a "tail" I put a push fit delrin tube, which seemed pretty tight. As always, I underestimated the forces involved. The inertia of the core on acceleration pushed it through the tube and into the shotgun wad, resulting in a very weird projectile actually hitting the plate. Still, pretty impressive damage.