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Posted: Wed Dec 01, 2010 4:35 pm
by POLAND_SPUD
uhmm.... 0.75" cal ? lol wtf?!
Finally something with a bit MOAR umph!
which already exceeds tolerable noise levels for an urban environment
You can use this as a refference site
http://world.guns.ru/ammunition/russian ... ges-e.html
check SP-3 and PZAM silenced pistol ammunition
ohh well I know you've already been considering this
Posted: Wed Dec 01, 2010 4:42 pm
by Fnord
JSR wrote:[fiberglass] ...as a wrap, but not as a filler, right?
As a filler it works fine. You usually can't cast it like normal epoxy unless you chop up the fibers a bit and agitate it, but in a case like this it doesn't need to flow very much.
A 50/50 weight ratio is probably fine for high-strength applications.
...
I imagine that 800psi prototype of yours that blew up and hid chunks of epoxy everywhere would not have failed with a mix of 'glass in it.
Honestly I've only worked with the stuff enough to become proficient but I still have nothing negative to say.
Posted: Wed Dec 01, 2010 5:09 pm
by jackssmirkingrevenge
POLAND_SPUD wrote:uhmm.... 0.75" cal ? lol wtf?!
Finally something with a bit MOAR umph!
Er... what did you think I was firing the CO<sub>2</sub> capsules out of?
ohh well I know you've already been considering this
To be completely honest, this is what it started out as... but a shot at 6x shattered the barrel (

) so I decided to give a conventional suppressor a go
I imagine that 800psi prototype of yours that blew up and hid chunks of epoxy everywhere would not have failed with a mix of 'glass in it.
I doubt it, the design was
really bad...
Posted: Wed Dec 01, 2010 5:10 pm
by jackssmirkingrevenge
double post

Posted: Wed Dec 01, 2010 5:57 pm
by POLAND_SPUD
To be completely honest, this is what it started out as
Now you're probably wondering 'Where the f... did he I hide the camera?!'
Don't bother... it's a ceiling cat
Er... what did you think I was firing the CO2 capsules out of?
ohh yeah I forgot. But IIRC the MV wasn't very high
Sure co2 capsules are relatively heavy, but there is always some room for improvement
Posted: Wed Dec 01, 2010 6:19 pm
by jackssmirkingrevenge
I need to seriously rethink shock absorption, but more importantly the challenge is to find a sabot that is strong enough to resist the firing forces but light enough to be easily caught, no mean feat.
POLAND_SPUD wrote:But IIRC the MV wasn't very high
Sure co2 capsules are relatively heavy, but there is always some room for improvement
Highest recorded for a 30 gram capsule was 308 feet per second at 12x. With the bigger chamber and slightly longer barrel I'm sure I can better that significantly, the issue is noise so it depends on how the suppressor performs.
Posted: Wed Dec 01, 2010 6:40 pm
by Selador
jackssmirkingrevenge wrote:Fnord wrote:er... fiberglass?
...as a wrap, but not as a filler, right?
Fiberglass is fine as a filler for epoxy.
You have to mix the epoxy in the first place, right ? Just cut up some fiberglass and mix it in at the same time.
Carbon fiber might be better.
And to add radial strength to an epoxy casting, wrap the fiber around it several times, layering epoxy along with it.
Bronze wool might be a good additive to epoxy, for added strength. (Fine steel wool wouldn't be worth much as a filler.)
Of course, with ANY filler, you start to get into whether the filler itself make a weak point. Kind of like stress fractures...
Posted: Wed Dec 01, 2010 6:51 pm
by jackssmirkingrevenge
Oxbreath wrote:Of course, with ANY filler, you start to get into whether the filler itself make a weak point. Kind of like stress fractures...
I've even used
airsoft BBs, for large areas where strength is less important I detest mixing too much epoxy so whatever is to hand to fill in goes

Posted: Wed Dec 01, 2010 7:05 pm
by JDP12
I was thinking of using steel BB's..
Posted: Wed Dec 01, 2010 7:20 pm
by jackssmirkingrevenge
JDP12 wrote:I was thinking of using steel BB's..
Word of caution, there is something out there with steel BBs encased in resin, and it's not built for strength

Posted: Wed Dec 01, 2010 7:47 pm
by JDP12
ahahaah excellent point. Maybe I'll just stick with airsoft bb's
Posted: Wed Dec 01, 2010 8:22 pm
by jackssmirkingrevenge
Back on topic, just to give an idea of scale, here's the latest compared to the rest of my hybrid family

Posted: Wed Dec 01, 2010 8:51 pm
by JDP12
wow..... that thing should yield some impressive power results!!
Can't wait to see, how long til its ready to fire?
Posted: Wed Dec 01, 2010 8:54 pm
by jackssmirkingrevenge
Technically it's cured, but it's early morning, not the best time to find out if the suppressor is effective or not

hopefully I'll try it out after work
Posted: Wed Dec 01, 2010 9:09 pm
by Lockednloaded
Holy sh*t, there's no way that suppressor couldn't work, that thing is overwhelming!