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Posted by: Socinus Jul 20 2011, 11:05 PM

I was creating a new character to test out a generator the other day and a couple things crossed my mind.

The first one was pretty straightforeward; is there a Y splitter for fiberoptic cables? The character I made is a sniper and he's hooked up via datajack to his rifle but also to a drone he uses as a spotter. I would think there would be SOMETHING at that point in time that would enable multiple fiberop connections.

The second one is a little more esoteric; what new advantages and tricks could snipers have at their disposal with Shadowrun technology? There's the obvious with better optics and a smartgun system, but what about beyond that?

Posted by: HunterHerne Jul 20 2011, 11:26 PM

The obvious Tacnet. Hook into enough Drones, and you have your own distraction/clean-up, spotters, and enough bodies to run a good tacnet that'd make many of todays snipers look like chumps.

Posted by: Mardrax Jul 20 2011, 11:45 PM

I wouldn't worry about a few extra fiberoptic cables. Your 'link is bound to have at least a few slots for them.

Also: agility and skillboosting 'ware will get you a long way.

Posted by: Mardrax Jul 20 2011, 11:48 PM

Don't forget though: a sniper's best friend is stealth. Don't skimp out on the ruthenium, stealth skills, get a to provide invisibility, silence (or multi-sense invisibility) and spirit-concealment, etc.

Posted by: Traul Jul 21 2011, 12:21 AM

If you are still using datajacks, just get a second one. They are dirt cheap both in and Essence.

Posted by: Miri Jul 21 2011, 12:54 AM

Or skinlink the rifle..

Posted by: MikeKozar Jul 21 2011, 01:05 AM

I had a scenario where the PCs were in a forest, and the opposition sniper had dropped a dozen minidrones along the likely avenue of approach. When they started taking cover behind trees, he would find them with the drones and use the indirect fire rules to shoot them through the tree - with a good sniper rifle and ammo, the extra armor is negligible.

Fair warning, though, that was an awful scenario. The players spent five hours inching forward, trying to beat the guy's stealth, while the troll drew fire. It was tedious and frustrating.

Posted by: HunterHerne Jul 21 2011, 01:14 AM

As it should be, in this case.

Posted by: MikeKozar Jul 21 2011, 01:56 AM

...how so? I considered it a failure, since as a GM I'm trying to run a fun game.

Posted by: HunterHerne Jul 21 2011, 02:07 AM

I would find it an interesting challenge, were I a PC. But, I usually take odd things no one else really thinks about.

For example, in one run dubbed "The Tower" my Troll Wuxing magician focused on metal spells (pre-SR4A) used Slag [Armour] on a Troll heavy tank, after spending edge, the opposing troll was nude, and easy picking to the rest of the team. I also used a Poltergeist variation to create a cloud of metal grit (bullets, gunpowder, etc.) to diffuse a lethal security laser grid, and get through it without major issue.

Posted by: Marwynn Jul 21 2011, 04:45 AM

Your team had no Matrix specialists or a Rigger to take care of the Drones? No Magician to summon a Spirit and kill the sniper? Or do other useful magical things like say Trid Phantasm (F5 but still).

I'd view it as a challenge, but it does depend on the team makeup.

1) There's probably a fiber optic "hub" or at least multiple ports. However, I'd consider modifying the weapon at least with a Skinlink. Unless that interferes with your cool-factor, in which case, plug the Drone into your Commlink instead.

2) Well, Drones can actually be both the Spotter and/or Sniper depending on the scenario. Rotodrones are your friend. An Awakened Sniper would be dangerous, a Spirit with Concealment can make it difficult to be perceived and the Sniper can carry gear that will defeat tech that doesn't need perception rolls (mostly).

- Holoprojectors' images require 2 hits to be seen as fake, and man some NPCs can't even buy that many hits.
- An Adept of mine (Speaker's Way) very convincingly ordered several people to "Stand up!" in the middle of a gunfight with a lot of cover. Two of the team's snipers took most of them down, the Adept was the bushwacker of sorts (and killed three by himself).
- I believe WAR has sensor rounds, where you can shoot a bullet with some sensor enhancements. I forget the details, but it's a nifty trick I want to try sometime. Cheaper than sending a Drone, but at least you can re-use the Chameleon-ized Fly Spy if it's not spotted.
- Most Sniper Rifles can be modified to fire Full Auto. If your GM lets you mod it with a Drum, go for it. Otherwise, you can consider a Battle Rifle instead which should be modified with a Drum and Full Auto (2 slots total).
- Krav Maga's Take Aim as a Free Action will let you use Vision Magnification to remove any range penalties.
- WAR also has some shrouds (camo and ruthenium and thermal I believe) which would go great with your Chameleon (or Ghillie) Suit.

Posted by: MikeKozar Jul 21 2011, 04:51 AM

My players were pretty sick of "interesting challenges" after having me as a GM for a year. I stranded them in an Arctic base full of cannibals, played cat-and-mouse with a kunoichi on an ex-Soviet aircraft carrier, initiated a Mexican standoff in a fireworks factory, sent them to recover a psychic warform cybergrizzly, trapped them in a high-rise elevator controlled by a homicidal hacker, convinced them to jump-start Ragnarok, established the Seattle branch of the Azatlan Bloodsport league, trapped them in a cave full of Shedim, pioneered a field-expedient invisibility counter with a fire hose and an electric fence, and hid a dozen ghouls in the basement of their bed & breakfast. These guys are probably praying for boring.

Posted by: crash2029 Jul 21 2011, 06:30 AM

Dude. I wanna play in that game!

Posted by: CanRay Jul 21 2011, 06:32 AM

Bah, Mexican Standoff in a fireworks factory... Pah!

Munitions dump! Go big *BOOOOOM* or go home!

'Course, I grew up in a mining town.

Posted by: HunterHerne Jul 21 2011, 11:43 PM

Those are some interesting ones. I had my players meet a Jason Voorhees clone (Free spirit inhabiting a Giant, using PC spirit creation rules, with regeneration), after his murder of the teenagers at the lake (the run involved figuring out what the hell happened there. They figured it out); one player gave me access to using a Ninja school against the group (via the enemy quality); was about to send them after a toxic Lindworm living in the sewer (created using Prime runner rules); and sent them on a non-lethal mission, where the objective was to get the information without setting off the alarms (they would still get paid, just not as much).
My setting is a little light on the nuyen. So, in order to get ahead, they had to take every advantage they could.

Posted by: Starmage21 Jul 21 2011, 11:54 PM

Pfft, I'd open fire.

Posted by: MikeKozar Jul 22 2011, 01:26 AM

...yeah, funny story - so did they.

Posted by: HunterHerne Jul 22 2011, 01:55 AM

How many survivors?

Posted by: MikeKozar Jul 22 2011, 04:52 AM

Well, the scene was that the local fixer was meeting a mafia drug-runner, and set up the exchange in a fireworks factory he owned. The fixer claimed to have a magical gimmick that would keep him alive if the drug runner decided to start shooting, while the mafioso was incinerated in the resulting inferno. The PCs' pointman, a heavily-modded Fomori Troll, determined that the mafioso was messed up enough to take the shot out of spite and went for a headshot, hoping to defuse (literally) the situation and grab the goods. The mafioso was chromed enough to survive the shot, but wound up at the epicenter of a 90P blast a few IPs later. Our Troll was far enough away that he only got a face full of 36P; as I recall, he soaked 15, trauma dampener dropped it to 20, and he had enough Body that it dropped him into overflow, but not dead. His backup at the treeline was a medic mage, who had him stabilized and back on his feet so fast that they almost didn't see the local fixer walking away with the briefcase.

Moral of the story is, Troll tanks are kind of hard to kill.

Posted by: Runner Smurf Jul 22 2011, 05:41 AM

Be prepared for the GM to get annoyed with the rules and (possibly) with you if you play a dedicated sniper. The ranged combat rules are broken when it comes to sniping - it's nearly impossible to miss against an unaware target at ludicriously long ranges. And if the target isn't unaware, then you haven't done your job as a sniper.

As a GM, sniper players suck. There's not much you can do to counter them without being an absolute jerk - the sniper is (typically in SR games) off on his or her own, and when that force 5 spirit shows up, they are pretty much toast. There's only so many times that the sniper's hide can be stumbled upon by random passersby or noticed by a recon drone before the player gets killed or annoyed. But if you don't do stuff like that, the character is just sitting a klick out from the target site, and occasionally blowing the head off a guard. It gets dull, and leaves the sniper with little to do. Which kind of makes sense - real snipers spend most of their time in a hide, waiting for hours and days for the target to appear.

The other problem with snipers as a GM is what's already been mentioned: there's not much the players can really do about it. It's basically a case of having a player roll a ludicrously impossible perception test to notice a concealed guy a mile away. They fail the roll, and one of the PC's head explodes. Party panics, calls in a few spirits, and the sniper either flees or gets gacked by a spirit (or...God help the team...his spotter is a mage). End of encounter.

For that reason, I have a "no sniper" house rule: if you don't do much sniping, I won't do much sniping. Does sniping make sense? Heck yes! It's terribly effective! Is it fun? Welll...not so much.

On the other hand, if you are playing a sniper, I highly recommend doing it as a sorcerer. Eat an essence point for cybereyes and a smartlink, if you are "old school". A bunch of longarms skill, some infiltration skill and the basic spellcasting stuff. Throw in an invisibility spell, a levitate spell and a slay spirit spell, and you can deal with just about any counter-sniper stuff that they can throw at you. A few good guns, a few good scopes, and you have yourself a very badass sniper.

My 2-nuyen.

Posted by: CanRay Jul 22 2011, 08:43 AM

Shipyard. Shipping Container of something dense and heavy. Crane. Strategically placed Maguffin.

Posted by: HunterHerne Jul 22 2011, 12:18 PM

Using more lethal rules helps, too. In my game, the troll would likely have lost a couple body parts (and needed reconstructive surgery to be recognizable, likely resulting in a loss of 1 or 2 charisma), the mage wouldn`t have been able to heal him (at least, not with the heal spell. streamlined it with the rest of the magic rules so boxes to be healed=force of the spell. Stabilize would have helped, still), and the Troll, even if he did survive, would be spending a lot of time in recovery (assuming he had 10 body, at 20 boxes damage, he would have a -5 penalty to his heal check (15 boxes, assuming he didn`t have High pain threshold. 5 overflow) and would likely spend at least 2-3 days unconcious (baring a medicine check to watch over him, and help him heal).

Edit: Fireworks tend to cause fires, too. So that would add more damage to the troll (I enforce the "What catches fire" rules)

Posted by: Socinus Jul 24 2011, 08:21 AM

What are the rules/benefits for assisting in combat rolls? IE: A spotter for a sniper

Posted by: Marwynn Jul 24 2011, 05:07 PM

Spirit of Man at Force 6 (Oversummoned with Levitate and another spell of your choice)
+ Mage with a Battle Rifle, Vision Mag, and a Drone Spotter
= Levitating, Concealed, auto-fire "sniper"

Drones come by, he can zap with Lightning Bolt. Spirits? Stunbolt from him or his Spirit, depending on the services.

(His "getaway" vehicle is a Segway with Lighter Than Air modifications.)

Counter? One wagemage with Mana Static and a good perception roll. My Mage almost fell to his death before the Segway could be summoned... Ahh Levitate, the cause of, and solution to, most of life's problems.

Posted by: UmaroVI Jul 24 2011, 05:34 PM

My rule of thumb with snipers is sniper is a thing you can do, but is not a role. Don't make a sniper, but feel free to make a character who can snipe when the situation calls for it.

Posted by: Traul Jul 24 2011, 05:49 PM

Nothing on its own, you need to add a Tacnet to make it work. Then you can get Initiative and combat pool boosts.

Posted by: DWC Jul 24 2011, 06:18 PM

WAR includes rules for directing fire, giving bonus dice on a ranged attack after a successful Leadership test. It isn't perfect, but it is the closest to spotting that SR has.

Posted by: HunterHerne Jul 24 2011, 06:54 PM

Isn't there a rule section that says the spotter can make a perception test and add the hits to your firearms test-6?
Edit: I've always believed it should be more of a communication test to accurately describe the details needed, maybe negotiation or leadership (haven't read War!), possibly maxed by the perception test.

Posted by: Tymeaus Jalynsfein Jul 24 2011, 10:02 PM

Information Guided Targeting is in Arsenal...

Posted by: HunterHerne Jul 24 2011, 10:09 PM

It's still around, and gives spotters a mechanical use before WAR!

Posted by: Traul Jul 24 2011, 10:16 PM

That's for indirect fire. When the sniper can see his target, using indirect fire will usually cost him dice (-4 + hits on the spotting check).

Posted by: HunterHerne Jul 24 2011, 10:20 PM

THat is true, unless the spotter is very good. But that particular question didn't specify whether or not the sniper could see the target. Both answers are legitimately useful, to their respective situation.

Posted by: Tymeaus Jalynsfein Jul 24 2011, 10:24 PM

And yet, a Spotter, unless he is with the Sniper, will be seeing things from a different prespective, and therefore will be a FO for the Sniper. This is the definition of Indirect Fire. The Sniper cannot see his target directly.

If the Sniper has Direct LOS to the Target, then the Spotter can cover the Sniper, and perform some of the calculations for him? In this case, a Tacnet/Smartlink combination is the preferred method.

In the real world, the spotter is typically co-located with the Sniper, and processes most of the targeting calculations before giving them to the Sniper. Range, Movement Speed, Direction of movement, angle of shot, lead factor. These are all calculations that a competant Sniper or Spotter can calculate. Sounds an awful lot like a Tacnet in combination with a Smartlink to me.

Posted by: Traul Jul 24 2011, 10:25 PM

If the sniper cannot see his target, he will have a hard time damaging it. Although sniping through a wall is possible with a Barrett, indirect fire was mostly meant to be used with curved trajectories that can reach their target even if the straight line of sight is blocked.

Posted by: Tymeaus Jalynsfein Jul 24 2011, 10:28 PM

This is true. I even Practiced it extensively when I crosstrained as a Machinegunner in the Corps.
But in game, with the Weapons available, Indirect Fire through walls is a viable option.

Posted by: KarmaInferno Jul 26 2011, 07:23 AM

I am reminded of a story involving an old Soviet soldier, having to shoot at someone WAY out of range for his AK, telling his subordinate spotter to "walk me onto the target".

He then proceeded to point his rifle upwards at a high angle and rain bullets down on his target using a ballistic arc.







-k

Posted by: Socinus Jul 26 2011, 05:28 PM

I cant imagine that'd be very effective.

If the bullet kept a ballistic trajectory, I could see that working. But if you shoot the bullet too straight up in the air, it'll stop once it's kinetic energy runs out then drop to the ground like a penny. It'd irritate someone, but not kill them.

Posted by: Smokeskin Jul 26 2011, 06:46 PM

Of course it kept a ballistic trajectory. I just put the 7.62x39 through a ballistic calculator, and at 650 yards it has 1000 fps, at 1000 yards it has 800 fps, at 1300 yards it has 700 fps. It'll be more like getting shot with a low calibre pistol than a rifle, but still very much like actually getting shot.

Posted by: Miri Jul 26 2011, 07:04 PM

I infer from the "high angle" reference that the muzzle of the gun was pointed between 45 and 89 degrees from the horizontal. So the round would travel very high up then turn over and fall and most likely hit terminal velocity before it hit the ground.

So yes, the triggerman could have done a "point the muzzle above the target so much that he can't see said target through the sights" and let bullet drop bring the round to target. Or he could have pointed the gun nigh on straight up and used a very high angle of attack path.

Posted by: Smokeskin Jul 26 2011, 08:50 PM

I'm pretty sure you infer wrong. There is absolutely no point in going above 45 degrees. You get shorter distance, lower velocity at target (you probably won't even have the bullet impacting nose first if drag can't overcome gyroscopic forces, it might even not be spinning along its length axis anymore), longer flight time over which wind will move the target so accuracy becomes even worse. A soldier will know that all weapons use flat arcs except for mortars, and I doubt there's any chance you can get any sort of consistency from high-arcing small arms fire.

High angle probably just meant much larger than what you'd normally use for shooting.

Posted by: Socinus Jul 26 2011, 10:46 PM

That was the impression I got from the story.

Posted by: Stahlseele Jul 27 2011, 12:01 AM

should that sub title not be "reach out and (double)tap someone"?

Posted by: CanRay Jul 27 2011, 12:12 AM

Nah, the double-tap was developed for the 9mm to ensure that the person stays down when shot, IIRC.

Snipers are the "One Shot, One Kill" types. I forget what one book was titled, but it was about the cost of one 7.62mm NATO round...

Posted by: Tymeaus Jalynsfein Jul 27 2011, 12:36 PM

I was always partial to "93 Confirmed Kills" myself.

Posted by: Smokeskin Jul 27 2011, 12:58 PM

So let's see.

Either the soldier actually fired his weapon in a wholly ineffective way against his better knowledge.

Or the soldier fired the weapon effectively, and either KarmaInferno heard the story wrong, or the guy who told him the story told it wrong, or KI told it wrong, or "high angle" just means high compared to normal shooting but not above 45 degrees.

Posted by: Tymeaus Jalynsfein Jul 27 2011, 01:50 PM

Yeah, Sounds about right...

Posted by: ZeroPoint Jul 27 2011, 08:46 PM

loved that book by the way

Posted by: Tymeaus Jalynsfein Jul 27 2011, 09:12 PM

As A Marine, it is almost required reading material...

Posted by: Socinus Jul 27 2011, 09:34 PM

Or you could, y'know, not be a dick about it.

There are A LOT of battlefield myths floating around and I simply pointed out something that struck me as odd regarding the story and questioned if it wasnt possibly one of the multitude of mythology regarding what does and doesnt happen in war.

Posted by: Mardrax Jul 28 2011, 12:00 AM

Fixed that for you.

Posted by: KarmaInferno Jul 28 2011, 01:00 AM

Pretty much this.

Also, I think the intent was to get an Afghani sniper to duck or otherwise stop shooting at him, not with any real hope of actually killing the guy, but he scored a lucky hit and took out the sniper's rifle.





-k

Posted by: CanRay Jul 28 2011, 01:38 AM

Still prefer the tankers solution to snipers.

Then again, I also like explosions...

Posted by: MikeKozar Jul 28 2011, 04:15 AM

That's the third post you've made which attacks KarmaInferno for his improbable Soviet anecdote. Just curious - were you looking for a retraction, an apology, or both?

I did some Googling, and it looks like machine guns have historically been used in indirect fire mode, particularly when ammo is plentiful and area denial is an objective. One example given is on the Western Front in WWI, where machine guns were used to pepper the area behind the trenches to make resupply difficult. Source: http://www.ww2f.com/small-arms-edged-weapons/51925-indirect-machine-gun-fire-effective.html

The trick seems to be that historically, it is used as suppression fire, and enemy casualties were not the main objective. There seems to be some question as to how lethal a lucky hit from an indirect barrage of machinegun fire would be, but if you're just trying to harass enemy movement and logistics, it could be of significant psychological value.

As far as sniping someone at close range with an assault rifle, by shooting nearly straight up? Seems like more trouble then it's worth. After all, situations like that are what grenades are for.

Posted by: Blitz66 Jul 28 2011, 04:47 AM

I don't know how true it is, but my high school physics teacher said that a bullet fired into the air would come down with almost exactly the same force it had when it left the barrel, because air resistance on it is negligible and gravity would act equally to slow it down and then to speed it back up, over the same distance. So the force shouldn't really be an issue.

The real problem is aiming. Even if you had a formula on hand to calculate the precise angle you need, the best it could do, in my opinion, would put it in the center of a fairly wide circle that the bullet will fall into. Every tiny irregularity affecting its flight path would have the full length of the parabola to alter the trajectory. So yeah, you could put lead into the air for indirect fire, but unless you're firing into an enemy mosh pit, you're probably not going to hit anything worth hitting, even with the perfect angle provided to you. Cover fire is the only really effective way to use it.

Unless you happen to have an enemy mosh pit handy. In that case, have fun.

Posted by: KarmaInferno Jul 28 2011, 05:15 AM

As I said a few posts ago, "high angle" meant "higher than is normal for direct fire". Apologies if I was unclear.

Mythbusters did testing on actual high angle gunfire, though, and concluded that if the round was being fired at a steep enough angle to actually have gravity be able to significantly bleed off the force, then yes, the bullet would be more or less non-lethal when it finally came back down. This happened mostly at very high to vertical angles - the bullet would lose momentum and slow down, stop, and gravity would pull it back down. Really, it would be no different than someone up at the apex of the bullet's flight just dropping a bullet. At worst maybe you'd get a bruise if it hit you.

However, at lower angles where the bullet can mostly maintain it's forward velocity throughout it's arc, the round was probably still very much lethal if it actually hit someone. There's been actually quite few incidents of accidental shootings this way - one medical center in LA reported in a ten year span in the 80s to the 90s over a hundred cases of folks getting hit by bullets fired into the air around the holidays. About a third were killed in the accidents.

It's not true. The amount of force exerted by the powder charge of a bullet being fired is MUCH greater than anything gravity can impart to the same bullet. The only reason gravity can stop a vertically fired bullet is because gravity exerts a continuous downwards force, whereas the bullet's upward energy is supplied all at once from the powder charge.

Also, the story I related, if it is indeed true, had the soldier using multiple rounds, adjusting his angle as his spotter told him how far he was off target. Which is what "walking fire' means.



-k

Posted by: CanRay Jul 28 2011, 07:39 AM

Math is hard. I'm going to go make cookies for the boys. Tee hee.

Posted by: Smokeskin Jul 28 2011, 08:50 AM

I don't think there's anything wrong with KarmaInferno's story. Walking fire in with a spotter isn't uncommon with for example tri-pod mounted machine guns. The technique can be used without a mount, but it is very difficult because you're aiming at a spot in the air and have to correct from that - which is why it is a good story that a guy does it with an AK-47.

It was only the interpretation that he was aiming at an angle above 45 degrees I was objecting to. I wasn't looking for anything from KarmaInferno, except maybe the confirmation that the story wasn't about aiming above 45 degrees, which he gave. He and I are seem to be in perfect agreement on it.



Indirect fire doesn't have to be plunging though. If the terrain is right, you can place yourself so a small hill covers your position, but the bullets can arc over it and hit the target without plunging. Much more deadly and much more precise. If you want to drop bullets down into trenches, you'll need plunging fire by firing closer to vertical. It needs a mount made for it I would think, or digging a hole for a mount so it is steady and pointing upwards though, as most mounts won't elevate that high. Without elevation markers or some other way of aiming, you'd be very hard pressed to get rounds falling into the area for any type of indirect fire.

Posted by: Traul Jul 28 2011, 09:06 AM

You missed the point. The gravity magnitude does not matter. Gravity slows down the bullet on the way up, then it accelerates it on the way down, and the two exactly cancel each other. If the target is at the same altitude as the shooter, the bullet reaches him at muzzle speed. What if you take the same shot on Jupiter? Muzzle speed. And on the moon? Muzzle speed too.

The only thing that really slows down the bullet is air friction. Indirect fire is less lethal than direct because the trajectory is longer so the bullet suffers from more friction. Gravity has nothing to do with that.

Posted by: Smokeskin Jul 28 2011, 09:24 AM

Under normal firing, the drag forces on the bullet is strong enough to overcome the gyroscopic effect and keep it pointing nose forward. If you fire it close to straight up, at the top of the arc the trajectory changes direction quickly while the air speed is so low the drag can't overcome the gyroscopic force. So the bullet is now travelling somewhere between backwards and sidewards through the air, and drag destabilizes it - the axis of spin remains largely unchanged compared to the ground, but the bullets orientation changes so it is no longer spinning nose-to-tail (sort of like a spinning top as it falls). I'm pretty sure this is what mythbusters saw, the projectiles were hitting the ground sideways, but they misinterpreted why - I believe there was still spin along a vertical axis, but the bullet had turned so it's length axis was describing a cone.

Falling that way, the bullet has high air resistance and won't hit hard, and getting killed by that would be very unlucky.

A bullet that can keep its nose oriented in the direction of flight however, that will hit very hard, especially a rifle bullet with a high ballistic coefficient - it is very aerodynamic and has a high sectional density, so its terminal velocity will be significant.

Posted by: Smokeskin Jul 28 2011, 09:39 AM

Air resistance is very significant. The round I use for hunting loses 32% of its velocity in just 300 meters of flight. Even a .408 Cheytac round loses over 10% of its velocity over 300 meters.

Because of this, the bullet won't go nearly as high as would be needed to accelerate it back up to muzzle speed even if it was in a vacuum on the way down, and air resistance will slow it falling down too. And is I commented above, if fired too straight up, it won't come down nose first, making it even worse.

Posted by: KarmaInferno Jul 28 2011, 05:31 PM

Incorrect.

A) Escape Velocity is a little above 11000 meters a second.

An AK can generate barely 715 meters a second. Even on a planet with no atmosphere, gravity would still eventually overcome the bullet's momentum and drag it back. Air friction does have an effect as well, but it's not the only effect in play.

B) There is a maximum downward force gravity can impart to a bullet.

You know that air friction you mentioned? Applies against gravity too. Only since the overall pull of gravity at any given point is much lower, you reach the point where the downward pull of gravity is equal to the resistive effect of air friction MUCH faster. At this point gravity cannot accelerate the bullet any further. This is known as terminal velocity.

The gun overcomes the air friction on the upwards leg of travel by sheer massive force.




This part is somewhat true. However, if the AK is generating 1500 foot pounds of force to a target, and 600 foot pounds is the lethal amount, reducing the bullet's striking force to 1200 FP or 1000 FP is still "lethal", even if it is technically "less lethal".





-k

Posted by: MikeKozar Jul 28 2011, 05:43 PM

No, no, of course not. Per the linked webpage, the indirect fire wasn't going into the trenches, but rather being spread around the field behind the trenchworks. That is to say, if you were trying to run supplies in from the next town, you would need to worry about stray bullets until you got into the trenches, and that was deliberate. I suspect that this only works if the elevation to drop behind is reasonably low and the distance is reasonably far, but I would probably consider letting players in my game use a heavy weapon for suppression fire over a wider range if the situation was right and the enemy had appropriate odds of a miss.

Posted by: Mardrax Jul 28 2011, 05:54 PM

I think he was just talking about the bullet impacting the ground at the same speed it left the muzzle, if it'd be fired straight up. This would be mostly correct when ignoring air resistance, which a high school physics teacher would often be happy to do. (mostly, because I'm assuming the muzzle isn't at ground level)
Sadly, you can't.

While a bullet is generally shaped for optimal aerodynamics, and fired from a rifled barrel to keep it on a course that makes maximum use of that, air resistance is still considerable on an object with that kind of speed. When it comes back down, it likely loses the stabilising spin, starts tumbling and rolling, and aerodynamics go to hell, increasing air resistance manifold.

This not only makes impact speed smaller, but very likely also makes impact area larger, since it's unlikely the bullet strikes point-down. This distributes the force over a much larger area, which decreases trauma, and greatly decreases chances of penetration.

Posted by: Aku Jul 28 2011, 06:04 PM

This was found in the aforementioned mythbusters episode as well, iirc. instead of getting a "hole",shaped like a bullet, the ground had an oblong indention, indicating that the bullet had turned sideways and was tumbling on its return trip.

Posted by: Smokeskin Jul 28 2011, 06:22 PM

This is most likely not the case though. The axis of spin is still vertical, but the bullet just isn't pointing nose up. External ballistics studies have shown this, and it is very difficult to imagine the force that would eliminate the bullet's spin.

Posted by: Aku Jul 28 2011, 07:11 PM

Posted by: Mardrax Jul 28 2011, 07:17 PM

Shame Mythbusters is far from a reliable source. They've messed things up on more than one occassion.

Posted by: DWC Jul 28 2011, 07:21 PM

The same air resistance that saps the round's forward (or vertical in this case) velocity is going to degrade the angular momentum, reducing the spin. The forces are easy to imagine from a fluid mechanics perspective.

Posted by: CanRay Jul 28 2011, 08:38 PM

There's only one solution to this: TO THE FIRING RANGE!!!

*Runs off and comes back sheepishly* Um... You folks in the States can do that...

Posted by: Tymeaus Jalynsfein Jul 28 2011, 08:47 PM

Heh... No Range, eh CanRay? Poor Canadian...

Posted by: CanRay Jul 28 2011, 08:49 PM

No range, no firearm, not wanting to deal with all the watch lists I'd be put on for purchasing a legal one with today's laws...

Damned 'Tories, I agree with them on one thing, and it's the one they bail out on.

Posted by: Tymeaus Jalynsfein Jul 28 2011, 09:07 PM

Posted by: CanRay Jul 28 2011, 09:09 PM

Don't even get me started on the firearms registry and the travesty that's been.

Back to shooting people in the face for money at one mile, please, before I get started.

Posted by: Tymeaus Jalynsfein Jul 28 2011, 09:11 PM

How about that BARRETT? Hell of a Rifle...

Posted by: Stahlseele Jul 28 2011, 09:33 PM

And it's kinda legally obtainable right?

Posted by: Tymeaus Jalynsfein Jul 28 2011, 09:55 PM

Costs about $9,000 or so, yes. For Hunting, of Course.

Posted by: Stahlseele Jul 28 2011, 10:00 PM

of course.
for like.
i don't know . .
what IS ther to hunt in america?
i mean, what is LEFT to hunt?

Posted by: Traul Jul 28 2011, 10:13 PM

Liberals?

Posted by: Tymeaus Jalynsfein Jul 28 2011, 10:17 PM

Ahh, Come on...

In Colorado Alone:
Bear
Elk
Moose
Antelope
Deer
Mule Deer
Turkey

Our Ranch in Texas has
Deer
Mule Deer
Sika Deer
Axis Deer
Russian Wild Boar
Javalina
Antelope
Black Bear (Though you better be mauled if you shoot a Bear in Texas, as they are not allowed for hunting, and will get you arrested because there are not that many on the Edwards plateau (15 to 20 known bear in 1995)

Of course, none of these need a Barrett... My 6.5mm Swedish works on all but the Bear
Of course, the Barrett DOES work for Liberals...

Posted by: Miri Jul 28 2011, 10:28 PM

And everywhere else.. politicians.

Posted by: Smokeskin Jul 28 2011, 10:31 PM

A rifle with a 1:10" twist at 800 m/s will spin 2,400 times per second or 144,000 rpm. That's a lot of spin you need to reduce by surface friction alone, quite different from the forward movement that also has to push air aside. Imagine the sort of friction needed to reduce spin by 200 rps or 12,000 rpm EACH second - it would still take 12 seconds to get rid of the spin.

As it starts to fall back to earth and the bullets orientation changes, it now has to push air aside to spin though. But even if we imagine the bullet tip is 1 cm away from the spin axis, this is only 6.3 cm circumference per revolution, so it is only rotating at about 150 m/s, and that's the tip, the rest of the bullet is moving slower. That's fairly slow and it won't be enough air resistance to bleed away 144,000 rpm of spin, especially when you consider that the air resistance drops as the spin slows.

So sure, the forces are easy to imagine, but once you quantify it, it looks very different.

Also, doppler radar measurements of bullets in flight confirm this. Bullets don't lose their spin in flight, period.

Posted by: Blitz66 Jul 29 2011, 12:02 AM

My family's farm in Kansas is one of the best places to hunt whitetail dear in the country. There are also coyotes, bobcats, wild turkey, and quail.

So, apparently my high school physics teacher was wrong, and dismissed the air resistance incorrectly. Good to know. I'm not buying the idea that the spin stops, though. Insufficient force acting on it, as demonstrated by numbers and tests, apparently.

Posted by: CanRay Jul 29 2011, 12:15 AM

Scared Canadian Tourists.

Posted by: MikeKozar Jul 29 2011, 03:10 AM

The thing to remember about America is that it is *BIG*, as in there is a *lot* of undeveloped spaces where there are still some big critters. I've had work about 8 miles from Seattle, and they mentioned that they had brown bears going after their birdfeeders. A friend went to a tech conference in another state and was warned by the front desk staff before he went jogging at dawn, because that's when the local mountain lions are most active. Not to mention the sort of stuff you find in the Everglades - not hard to find stories of 7 to 10 foot alligators (that's about three meters, BTW) that wander into populated areas in Florida. The only thing I would consider using a Barrett on though would be a bull moose - those things are bigger then my car. I think those are mostly Alaska, though.

Seriously, those guns are for killing engine blocks.




Hey, now.

Posted by: KarmaInferno Jul 29 2011, 03:45 AM

I have a few friends from Europe that upon visiting the US, they are flabbergasted at driving for days and days and still not running out of USA to travel.

Hell, a couple of our states you can drive 800 miles in a straight line and not leave the state.

Tons of wildlife in them thar hills & woods.



-k

Posted by: Blitz66 Jul 29 2011, 04:36 AM

Now? Yes. Good idea. Since you suggest it, now is the best time for liberal-hunting.

Posted by: Mardrax Jul 29 2011, 12:57 PM

"Oh my $deity! I just shot you! Are you alright?"
"Oh, I'm sorry, I completely stepped into your line of fire there, my bad. You have my apologies. Would you like me to refund the bullet? I'm truly sorry."

Posted by: Tymeaus Jalynsfein Jul 29 2011, 12:58 PM

Heh... Awesome...

Posted by: Dreadlord Jul 29 2011, 04:10 PM

Wouldn't you also have to say that in French immediately afterwards?

Posted by: CanRay Jul 29 2011, 05:29 PM

And if you think the USA is big and spread out, try Canada and prepare to freak the hell out.

I know I did when I woke up in the Prairies.Only if it's written.

Posted by: MikeKozar Jul 29 2011, 10:40 PM

Sorry, I wasn't clear. When I said "Hey now! " I was trying to say that I know we're all friends here, but this is not the place to start flamewars about American politics. Maybe we could get back to talking about Shadowrun, huh?

Posted by: CanRay Jul 29 2011, 10:53 PM

Considering that Liberal is an actual political party in Canada, I was wondering if we were going to get a major hunting tourism boom up here again.

After they cancelled the spring bear hunts which cut the knees off a lot of Northern Communities, and increased the bear populations to where they started to be a problem to humans and the other wildlife in the area... Well, something new would be a good option.

Posted by: suoq Jul 30 2011, 12:58 PM

http://outdoornebraska.ne.gov/hunting.asp

In Nebraska, the only barrier to hunting is getting into the "overbooked the second they're announced" Hunter Safety courses. On the good side for us, the BSA summer camp out here offers Hunter Safety to all boys earning their Rifle Shooting or Shotgun Shooting merit badges, so my son is now good to go and a couple of the leaders who hunt have offered to take him with them this season.

-------------

On gravity: The deceleration force at any given height is equal to the acceleration force at any the same height or, in Portal Physics. Speedy thing goes up, Speedy thing goes down.

Air resistance and fluid mechanics are still serious barriers to velocity. Gravity is not.

Posted by: CanRay Jul 30 2011, 02:35 PM

In Canada, there is quite a bit of hunting that goes on. (http://www.arrogantworms.com/music/rocks-and-trees-3/).

Our obstacle is the firearms laws currently on the books which makes it really frightening to attempt to buy or inherit a firearm unless you got in when the laws went into place and you were able to get in through the Grandfather Clauses...