SpudFiles

would a silencer reduce the velocity of the projectile?
(short question)

Yes (short answer)

yes but not by much

Could be both yes and no, depending on how you design your silencer.

the filling material will take the energy from the bullet when it comes into the silencer..

A baffled type construction added to the end of the barrel could potentially increase your velocity. Perforating your existing barrel on the other hand would noticably decrease your velocity.

Like JSR said:
When your barrel is short compared to the chamber, and a silencer adds a bit of barrel then it may increase velocity.

I may not understand this right but basically to silence a weapon you want to use up all of the energy before it reaches the end of the muzzel. You can do this by either having a really long barrel or something for all that extra energy to expand into. I've heard of attachments that allows you to screw a soda bottle on the end of a pistol. Never tried it and never seen it... but in theory it would silence the weapon.
If you could do something similar you shouldn't see and decrease in velocity but it would still make the gun quieter. Ideally you would want the volume of the container to be slightly greater then the volume that the gas would normally occupy under no pressure.
This is all speculation so if I'm wrong feel free to correct me.
Good luck

hmmm i might have to look in to that bottle silencer, because if i remember correctely it is on the movie, shooter and he uses it to silence a .22 but the again that is a movie

I had heard about before the movie came out... but it would be worth while to look into.

(If I'm not mistaken) I'm pretty sure silencer's should not effect the velocity of your projectile (to a point worth worrying about) because they're main purpose is to absorb the bang, and being outside the barrel, shouldn't affect how the gun shoots.
And as JSR said, if anything, it would increase velocity if its on the end of/extending the barrel.
But if you make a "silencer" from the barrel itself (aka = drill holes at the end), that would decrees velocity. Otherwise, if it's an attached silencer that doesn't change the performance/shape of the barrel underneath, you should be fine.

Disclaimer: My knowledge of silencers comes from a guy who was the private gunsmith for a SEAL Team during the Vietnam war(*). My experience actually building/using silencers is very very limited, at best (there's that little thing called a "felony charge" that prevents me from playing around in this field much).

The basic principle behind silencer operation is two-fold....

1) Allow gun gases to expand into auxilary chambers.
2) Design those auxilary chambers such that they fill with gases faster than they discharge them and/or dissapate energy while contained within the chambers.

...There are several ways to do this. They all have advantages and disadvantages. The best at deadening sound are also short lived (only work for a few shots). The most durable aren't as effective at silencing the report.

The best designs result in a gun so quiet that the cycling of the bolt is the dominant noise in the operation of the gun (these designs DO affect muzzle velocity). The most durable designs don't do much more than remove the high frequency noises which makes it more difficult for the human ear to determine location (ie, it's still loud, but it's harder for somebody to know where it's coming from). Between those two extremes are a million shades of gray.

Yes, the full blown "provide enough expansion volume to allow the gases to expand to ambient" concept would work, but it results in a weapon that is unwieldy.... Or at least, that's the case with firearms. With spud guns this MAY not be the case since we're dealing with much lower pressures (although we are dealing with larger volumes so it's not a 'gimme').



(*) Basically, after a SEAL Team would come back to the states their first duty assignment would be here at the local base (an R&D facility). Their job - while here - would be to act as consultants on new infantry weapons; IE, to provide opinions on what would work in the field and what wouldn't. In any event, they were also allowed to make direct suggestions/requests/etc. Suffice to say that the master machinist who acted as their private gunsmith was a friend of mine.

And just for fun, some of his work...

(Note: Not ALL of that is his work)

D_Hall wrote:And just for fun, some of his work...

his doing? if so, sweet

jackssmirkingrevenge wrote:

D_Hall wrote:And just for fun, some of his work...

his doing? if so, sweet

Not his design, but he almost certainly did the machining on it (I can no longer ask as he's no longer with us.).

sorry to hear that. imagine what he could have told you about different things, and then changed them to spud guns and stuff like that.
of course if he did go right ahead and make a topic and start spilling the beans,,,, lol