Have you actual competence in science and GUN design?

What the fuck are you talking about? Is English your first language?
>half automatic
You mean semi-automatic?
>soundless
Silenced/suppressed?
>Ice bullets
Anything that isn't a dense metal or part of a dense metal will disintegrate as soon as you fire it. Stop being a retard who watches too many movies.
>No casings being expelled.
Get a revolver if you care

>>34942157
Read the sticky, vanishing bullets aren't worth looking into since they'll just end up vaporized, you'll need a fairly large bullet if it's going to be subsonic, a company that makes silencers is making an internally suppressed gun already so they will beat you to the punch with regards towards cornering the mall ninja/assassin/james bond market, you will have to manufacture your own caseless ammunition since no one makes caseless ammo, because no one makes caseless ammo no one would buy your gun.

>>34942208
1.
Sorry, I am German.

2.
Silencers are not truly silent, there is a lot of noise still from the weapons action and released gases.

3.
With small additives regular ice can made into a hard yet ductile substance, for example with a few percent of metal or wood dust (google pykrete).
Dry ice has a higher density and could possibly function well.
It would require internal cooling of the gun or ammo, but this can be cheaply and reliably achieved with a peltier element, for example.

4.
There is a trick to anti-forensically collect the expelled spent cartridges: Wrap a plastic bag around the gun and your hand/arm, and fire through the bag.

5.
Revolvers are notoriously difficult to seal completely between barrel and revolving cylinder. Gas escapes, noise is made, forensic evidence is produced. Not nearly good enough.

http://www.forgottenweapons.com/russian-silent-ammunition/

I know of those, but are they really 100% silent?
Is there no sharp "clack"?

Also they seem limited in capacity - 6+ shots would be useful to have.
And, while being already a design that proves good thinking, I wonder what Western nations
have come up with to solve that problem, or what else/better the Russians truly have - those silent
guns of the type you presented are already like 50 years old.
Also, they offer no self-vanishing quality for the bullet, while I know that their ammo was deliberately
made so that it would register as Ak47-projectiles in forensic bullet analysis to mislead deliberately.
In 2008 I heard truthfully-sounding reports of some Afghan man who reported that US special forces entered his house at night, in complete silence and darkness, and he swore they had completely silent guns, only the bullets` impacts in the walls and the shot bodies could be heard.

>>34942157
This is simplest option for a trace less firearm.

>buy 80% glock lower at gun show
>also buy threaded barrel for said glock
>build glock
>attach brass catcher to glock
>attach oil can suppressor to glock
>load with subsonic ammo (bought in private sale)
>commit crime
>throw it in a lake

>>34942157
Silenced Nagant with subsonic cast lead handloads.

>>34942157

You could reduce sound a lot more if you're willing to sacrifice things like accuracy and energy.

A very weak cartridge with a large suppressor using baffles and multiple wipes would be quite, but pretty useless outside of a demonstration.

I have no idea why you'd need these other than to commit a crime. If it's for committing crimes, the logical answer is obviously "don't do it". It's similar to when people want self-defense techniques, yet refuse to accept that the best and most essential technique is "not fighting".

>>34944036
It's not a crime if the CIA does it! :^)

>>34944036
>need