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child of insanity
ok, if you put an external gas vent onto a gun with internal, would they stack? as i'm not sure exactly how they actually work i need to know.
the way i see it, what doesn't get vented by the first one can be vented by the second. am i wrong?
Slump
Well, gas vents are all internal, though integral would be better. At it's simplest form, a gas vent is a hole drilled into the barrel of the gun so that some of the propellant pushes the gun in the direction you originally pointed it, rather than pushing the bullet.

If you've ever fired a gun that had any sort of power at all, you know that the recoil 'kicks.' Because of the timing involved, and where the kick occurs, the recoil of a single shot won't affect that particular shot, since it's basically from the bullet leaving the barrel (and the gasses and whatnot). However, you do have to reposition your arm after every shot. The larger the kick, the more repositioning you have to do. What the Gas Vent systems do is shapes the end of the barrel, up to and including holes, to move the recoil around a bit so that the recoil, which just as bad, is more consistant, and is forcing the gun to move in directions that minimize the effect of the recoil. It's the difference between the gun jumping 4 inches upwards and 4 inches towards you -- when the gun kicks towards you, you're still pointed as the same thing.

And explanation for the differing levels of effectivness and cost of the various levels of Gas Vent systems can be explained by saying that the more expensive ones are engineered for that particular gun, rather than the basic mod that any gunsmith can hack out, plus the person doing it is more experienced and better at doing it.

This is why in SR3, and almost certainly SR4, once a gas vent system has been added, it cannot be removed. It's literally part of the gun once you add it. It can't be unscrewed or unclipped the way a silencer or under-barrel weight can.

And you can't use a silencer with gas vents because a silencer captures the gas leaving the barrel and releases it slowly, causing less of a shock to the surrounding air (and thus less noise). You can't exactly catch the gas while letting it out at the same time.
Austere Emancipator
As explained by Slump, gas venting to reduce the (effects of) recoil works by redirecting the high-velocity propellant gases produced when a weapon is fired. A certain amount of gas at a certain velocity can only do a certain amount of work towards reducing felt recoil -- stacking gas vents makes no sense from a real-life perspective.

Not that that's an issue in SR3, since you can never have more than one attachment on the barrel slot -- if there's an "internal" gas vent there, you are not allowed to put an "external" one on it.

IRL, certain types of gas vents, like many muzzle breaks, are detachable, though not quite as easily so as, say, sound suppressors. They often also direct the gases backward, or at the very least reducing the amount of gases escaping forwards, reducing the backwards force of the recoil.
Dog
That's interesting, if I'm understanding it. Could one customize the gas-vent features of a favorite gun? "I tend to pull left, so put the vent here." something like that?
Austere Emancipator
Sure, you can get custom muzzle brakes to do that if you want to. Though learning not to pull left might be more effective.
MYST1C
QUOTE (Slump)
This is why in SR3, and almost certainly SR4, once a gas vent system has been added, it cannot be removed.  It's literally part of the gun once you add it.  It can't be unscrewed or unclipped the way a silencer or under-barrel weight can.

Of course, you could simply exchange the whole barrel, thus removing the attached gasvent.

QUOTE
And you can't use a silencer with gas vents because a silencer captures the gas leaving the barrel and releases it slowly, causing less of a shock to the surrounding air (and thus less noise).  You can't exactly catch the gas while letting it out at the same time.

A common houserule is that there are silencers built to fit over gasvents. As result the gun is silenced but at the same time the recoil-dampening effect of the gasvent is lost.
So you can choose between "noisy but less recoil" or "quiet but full recoil" depending on the situation.
Fortune
QUOTE (M¥$T1C)
A common houserule is that there are silencers built to fit over gasvents.

Can't be that common if it's the first I've heard of it. wink.gif

Not saying that it's a bad idea though.
Butterblume
Makes a lot of sense, but someone will point to the ingram smartgun and say that it has a sound supressor and gas vent.
Fortune
QUOTE (Butterblume)
... but someone will point to the ingram smartgun and say that it has a sound supressor and gas vent.

Yeah, but it's special! See my sig. biggrin.gif
dog_xinu
Gas Vents aka Muzzle Breaks generally make the weapon louder than normall due to how the blast is shot outward at roughtly 90degrees from bullet path. I know the AR15s/AK47s that I shoot that have muzzle breaks are much louder than the non muzzle breaked ones.

as for the rule about silerncers fitting over the gas vents, well it wouldnt work that way with today's technology but I do like that. People would have made a difference in how all that is done. And yes I do know some about silencers. I have fired through enough of them. biggrin.gif

my jaded opinions...
dog
hyzmarca
Actually, it wouldn't work well at all. The expanding gas would just push against the silencer's inner wall instead of providing downward thrust to counteract muzzle rise. Its all one system so it would be sort of like trying to fly by grabbing your pants and pulling upward.
Kagetenshi
I think the point is that you would render the gas vent (temporarily) nonfunctional, but still be able to switch between suppressed and unsuppressed fire.

I'm too tired to actually evaluate this idea.

~J
Raygun
QUOTE (dog_xinu)
Gas Vents aka Muzzle Breaks generally make the weapon louder than normall due to how the blast is shot outward at roughtly 90degrees from bullet path.  I know the AR15s/AK47s that I shoot that have muzzle breaks are much louder than the non muzzle breaked ones.

To you, the person shooting it. The level of sound pressure generated by the shot doesn't change, it has to do with the direction the sound waves are moving. To the person standing in front of the muzzle (be they in the path of the bullet or not), the shot is going to seem quieter than it would without the brake because the sound pressure waves are directed away from their position. It definitely won't seem suppressed in any way, but there will be less sound pressure directed toward them.0

QUOTE
as for the rule about silerncers fitting over the gas vents, well it wouldnt work that way with today's technology but I do like that.

It most certainly can work that way with today's technology. SSK Industries is particularly fond of that arrangement with their suppressors as the brake (which is machined directly into the barrel) directs gases into the rearmost expansion chamber of the suppressor (which extends over the barrel), keeping said gases from moving forward and out of the muzzle too quickly. Here's a pic.

QUOTE
People would have made a difference in how all that is done.  And yes I do know some about silencers.  I have fired through enough of them.

Hmm. Then you should be aware that in reality, sound suppressors tend to reduce recoil in addition to sound pressure all on their own. All silencers/suppressors are designed to contain and reduce the pressure of the muzzle blast and release it slowly in order to prevent the BANG! As such, the muzzle blast is not only kept from pushing against the muzzle of the barrel (which is a source of what we perceive as recoil) it impacts the baffles opposite the muzzle, counteracting the rearward thrust of recoil. A similar effect, though slightly less effective (as the pressure is in the process of dropping very quickly) than a muzzle brake on its own.
child of insanity
how much compensation do you think it would provide? and a difference between a silencer and suppresor?
nezumi
QUOTE (child of insanity)
how much compensation do you think it would provide? and a difference between a silencer and suppresor?

I *BELIEVE* the difference is suppressors are real and silencers only exist in James Bond movies.
Fix-it
I think it's more of a Tomatoe/Tomahtoe thing, "Supressor" is the technical name, but the term "silencer" fits just as well.
child of insanity
actually from what i've seen there is a bit of a difference. suppressors don't work as well, but can be used on full auto, and can take more bullets from them. silencers not so much. first couple shots are almost completely silent, but they degrade easily. but my info could easily be out of date.
Kagetenshi
It's current, but it's also from the SR3 core book. Silencers are what you get if you run a suppressor through popular culture (or an advertising department).

~J
Raygun
Everyone in here should read this and this.
Cray74
QUOTE (Austere Emancipator)
Sure, you can get custom muzzle brakes to do that if you want to. Though learning not to pull left might be more effective.

Shadowrun's recoil rules are rather blind to shooters' skills. The impact of 2 or 3 points of recoil in SR3 can easily overcome the skill advantage of, say, firearms-6 vs firearms-2, particularly if pre-recoil target numbers started higher than ~3.
Wounded Ronin
What this thread needs is dueling banjo opposite video footage of one guy spraying rounds from a MP5SD and another guy spraying rounds from a UMP45 that's got a suppressor on it.
Raygun
Here you go. MP5SD vs. UMP45
Fortune
What? No hillbilly soundtrack? wink.gif
Raygun
Well, I guess you could open up another window and play this while you're watching the gun videos... wink.gif
Fortune
Now, somehow I just knew you wouldn't let us down. biggrin.gif
child of insanity
cool. you guys are the bestest:p
it's so great to have people who actually know what they're talking about to ask these things of... and you go over and beyond the call of duty! those vids were awesome and informative.
[/ass kiss mode]
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