How to: custom caliber ammunition

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wyz2285
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Wed Sep 05, 2012 6:27 am

[youtube][/youtube]
Simple+cheap way to make a perfect match sabot for sub-caliber ammo with custom size barrels :)
Last edited by jrrdw on Wed Oct 30, 2013 9:55 am, edited 1 time in total.
Reason: Fixed video.
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
PotatoEnemy17
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Wed Sep 05, 2012 12:27 pm

Wow, that's a great idea wyz! I should try that :) And what cannon was that in the beginning of the video?
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wyz2285
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Wed Sep 05, 2012 12:30 pm

That's my hybrid cannon.
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
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jackssmirkingrevenge
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Wed Sep 05, 2012 12:41 pm

Very nice tutorial as always :)

Here's another method: http://www.spudfiles.com/forums/sabots- ... 23677.html

The two can be combined, you could have a foil or paper wrap to centre the projectile then add a wax base.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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wyz2285
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Wed Sep 05, 2012 7:00 pm

Tutorial are like intros, with your own imagination that how things will work for you ;)
There are many ways, I just point a direction.
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
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MrCrowley
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Tue Sep 18, 2012 7:15 pm

Thanks for the inspiration, got off my ass this weekend and had a little fun:
[youtube][/youtube]

I was quite surprised at how effective and tough the sabots are. Although the wood was probably only radiata pine (i.e. a soft wood), I was pleased with the .223 and crossbow bolt penetration. The slug filled with 3mm BBs was also quite cool as the entry hole was the size of the wax slug but inside the hole the BBs had expanded out and formed a BB ring like a bearing.

As you've already demonstrated, wyz, these slugs are suitable even for hybrids.
Last edited by jrrdw on Mon Oct 28, 2013 11:58 am, edited 1 time in total.
Reason: Fixed video.
jonesy42
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Tue Sep 18, 2012 8:44 pm

wyz2285 wrote:[youtube][/youtube]
Simple+cheap way to make a perfect match sabot for sub-caliber ammo with custom size barrels :)


Don't you hate trying to match steel ball bearings and
inner diameter's of various tubing/pipe materials!
Very good idea wyz, are they accurate though?
Last edited by jrrdw on Mon Oct 28, 2013 11:54 am, edited 1 time in total.
Reason: Fixed video.
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MrCrowley
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Tue Sep 18, 2012 8:53 pm

Wax is reasonably light so if you shaped the wax in to a more aerodynamic shape with the ball bearing as the front of the projectile, you probably could get better accuracy than just shooting a ball bearing. Now that all depends on things like range, weight and performance. But at a decent distance a spherical projectile will dip, rise or curve to some degree* whereas an aerodynamic shape like the bottom drawing in the link above will only have gravity affecting its trajectory after leaving the barrel.

*a sufficiently heavy projectile, relative to its velocity, probably wont rise, dip or curve uncharacteristically. For example, a 10mm ball bearing will probably only dip in trajectory at ~200fps over a medium decent because it is too heavy/too slow to be affected by things like wind or spin.

Anyway, that's pretty much all assumption on my behalf; I doubt that actually shaping a wax projectile will be worth the extra accuracy (if it does result in any). JSR will be able to weigh-in better than I.
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Tue Sep 18, 2012 10:19 pm

[quote="MrCrowley"]Wax is reasonably light so if you shaped the wax in to a more aerodynamic shape with the ball bearing as the front of the projectile, you probably could get better accuracy than just shooting a ball bearing. Now that all depends on things like range, weight and performance. But at a decent distance a spherical projectile will dip, rise or curve to some degree* whereas an aerodynamic shape like the bottom drawing in the link above will only have gravity affecting its trajectory after leaving the barrel.

*a sufficiently heavy projectile, relative to its velocity, probably wont rise, dip or curve uncharacteristically. For example, a 10mm ball bearing will probably only dip in trajectory at ~200fps over a medium decent because it is too heavy/too slow to be affected by things like wind or spin.

Yes,... i have found the difference in accuracy is notable between 6mm and 9.5mm
steel ball, hence the difference in weight and wind effects that occur. Have you seen the
ammo that the Benjamin rogue .357 cal air rifle uses? Something like those would be
perfect.
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jackssmirkingrevenge
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Wed Sep 19, 2012 12:16 am

Good stuff MrC! Now if only we could introduce you to that friendly machinist...

I don't know why I was reminded of this amusing set of reviews for Veet hair removal cream for men:
hectmarr wrote:You have to make many weapons, because this field is long and short life
jonesy42
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Wed Sep 19, 2012 2:56 am

jackssmirkingrevenge wrote:Good stuff MrC! Now if only we could introduce you to that friendly machinist...

I don't know why I was reminded of this amusing set of reviews for Veet hair removal cream for men:

All thats left in the gentlemens "log cabin" now is a "marooned bag of agony" :D

Absolute gold, :lol:
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jackssmirkingrevenge
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Wed Sep 19, 2012 3:08 am

jonesy42 wrote:Absolute gold, :lol:
My favourtie by far was this:
Seriously, my once proud Biggles looks more like the lone equine survivor of a fire at a donkey sanctuary.
:D :D :D

*Ahem* yes, sorry for the thread hijack...
hectmarr wrote:You have to make many weapons, because this field is long and short life
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wyz2285
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Wed Sep 19, 2012 8:15 am

I was quite surprised at how effective and tough the sabots are. Although the wood was probably only radiata pine (i.e. a soft wood), I was pleased with the .223 and crossbow bolt penetration. The slug filled with 3mm BBs was also quite cool as the entry hole was the size of the wax slug but inside the hole the BBs had expanded out and formed a BB ring like a bearing.

As you've already demonstrated, wyz, these slugs are suitable even for hybrids.
If you make the wax slightly larger than the barrel bore, a "potato" a like air-tight fit can be archived. I was able to shot through a laptop screen with a nail using 3 bar with a 1.5l water bottle 3/4 ball valve gun, the tight fit completely compensated the slow opening valve. Check the shot at the end of the video, you can notice a delay between fully open the valve and the shot.
Also, with a wax sabot, rifling can be effective in any cases now. But for hybrids and combustions, you probably need more wax as some of them will burn off.
[youtube][/youtube]
Last edited by jrrdw on Mon Oct 28, 2013 11:46 am, edited 1 time in total.
Reason: Fixed video.
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
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