Bullet drop

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folmerveeman
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Bullet drop

Postby folmerveeman » Sun Oct 10, 2010 1:10 pm UTC

Would it be possible to utilize adjustable velocity in bullets (assuming that there is a way to adjust it) to actually use bullet drop as special weapon?
I mean, if a long-range sniper would fire a bullet at a window at like 45 degrees upwards, at a lower velocity than normal, it would go into the house at a certain arc as well, and for example hit someone hiding below it.

Is this enough for you people to understand? If not, please tell!

But I'm wondering, would it be POSSIBLE (not practical) to adjust velocity of bullets to utilize the arc?

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Re: Bullet drop

Postby Tass » Sun Oct 10, 2010 1:19 pm UTC

In general it would be moving fast enough to be dangerous at such an arc. Unless it is a cannonball.

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Re: Bullet drop

Postby folmerveeman » Sun Oct 10, 2010 1:24 pm UTC

Do you reckon it would be applicable? Because, essentially, it could allow you to ignore cover.

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Re: Bullet drop

Postby Mr_Rose » Sun Oct 10, 2010 1:46 pm UTC

folmerveeman wrote:Do you reckon it would be applicable? Because, essentially, it could allow you to ignore cover.

The thing is, avoiding cover is much easier to do with an appropriately timed fragmentation explosive (which are now available in calibres suited to sniper weapons) than with barrel/charge adjustments. Or by simply putting in an even bigger charge and going through the cover.
At least, that's the case in man-portable weapons, where variable charges would cause all sorts of logistical and reliability problems that no-one wants to have to deal with. Variable barrel inclination and propellant charge is already in use to circumvent cover in quite a lot of modern artillery, particularly naval guns.
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folmerveeman
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Re: Bullet drop

Postby folmerveeman » Sun Oct 10, 2010 1:54 pm UTC

Mr_Rose wrote:
folmerveeman wrote:Do you reckon it would be applicable? Because, essentially, it could allow you to ignore cover.

The thing is, avoiding cover is much easier to do with an appropriately timed fragmentation explosive (which are now available in calibres suited to sniper weapons) than with barrel/charge adjustments. Or by simply putting in an even bigger charge and going through the cover.
At least, that's the case in man-portable weapons, where variable charges would cause all sorts of logistical and reliability problems that no-one wants to have to deal with. Variable barrel inclination and propellant charge is already in use to circumvent cover in quite a lot of modern artillery, particularly naval guns.


So you're saying it's possible and could be semi-practical, but the need has been circumvented?

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Re: Bullet drop

Postby firechicago » Sun Oct 10, 2010 2:21 pm UTC

A couple problems off the top of my head:

1) Arcing a shot onto a man sized target over an obstacle requires a lot more precision than just compensating for drop and shooting "straight".

2) How is it you're able to draw a bead on this target that's behind cover?

3) For exactly this reason, when you get behind cover you get right behind it. The closer you are to your cover, the higher the arc of the parabola a bullet will need to take to hit you. That means that the shooter is firing almost straight up (and accepting the extreme inaccuracy that will result.)

4) In order to get a significant enough drop at ranges of less than about 100m (i.e. the ranges most firefights happen at) you would need to reduce the muzzle velocity from "you shot me, my internal organs now have the consistency of chunky salsa" levels to "you shot me, man that stung, I'm going to have a nasty bruise there tomorrow."

All this before considering the engineering problems of actually designing a gun that can reliably and extremely precisely determine a variable muzzle velocity.

All that said, the idea isn't totally crazy. I've heard stories of snipers doing this at extreme ranges (where they're already compensating for many meters of bullet drop). But the practical difficulties of making it work more often than once in a blue moon make it extremely unlikely to be worth the tradeoffs involved majorly redesigning their weapons.

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Re: Bullet drop

Postby Mr_Rose » Sun Oct 10, 2010 3:04 pm UTC

folmerveeman wrote:So you're saying it's possible and could be semi-practical, but the need has been circumvented?

I'm saying it's plausible, in that the physics work and the required mathematics is a solved problem, and it is highly impractical with chemical propellants, but yes the need has been circumvented anyway.
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Re: Bullet drop

Postby gorcee » Sun Oct 10, 2010 5:40 pm UTC

The military term for this kind of thing is "indirect fire." there are too many factors to do it effectively with a single bullet, but weapons such as the Vickers machine gun, used in ww1 and ww2 were often used in indirect fire roles. Artillery, of course, is also indirect fire.

I should also mention that machine guns don't really change the velocity (which can be accomplished by manipulating the amount of powder), but artillery very often does.

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Re: Bullet drop

Postby _Axle_ » Sun Oct 10, 2010 8:42 pm UTC

Quick Math :
Unrealistic, but ignoring moisture, terminal velocity and drag ( yeah, basically the real physics, but away from my usual books and just did the quick math in 2 minutes )

At a range of 1600 meters ( about 1 mile, near max range for snipers, at least good rifle efficiency range ). It would take ~18 seconds for the bullet to drop 1 meter below where it was shot from, if angled at 45 degrees above the horizon. The Muzzle velocity would be around 126 m/s

( I can type up my math if you want proof, but I basically just broke it out in X and Y components, 2 unknowns, 2 equations )

Real use :
Sniper fire and Indirect fire are in completely opposite side of the military strategy. Indirect fire is good guess work, taking a direct shot for 1 target is as precise as you can be. The math will be different, but 18 seconds is way too long for any efficiency at precision targeting. For taking a target out behind cover, its the reason something like the Barret M82 was invented. Goes through cinder blocks, small/medium sized car engines, etc.
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Eebster the Great
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Re: Bullet drop

Postby Eebster the Great » Mon Oct 11, 2010 1:32 pm UTC

I would like to add that entirely new bullets would have to be designed that can accurately arc. Current bullets will tend to wobble all over the place on the way down from even a slightly steep arc, so that really wouldn't be acceptable. You'd get better accuracy with a musketball.

But I'm sure designing the bullets would be the least challenging part.

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Re: Bullet drop

Postby Thesh » Tue Oct 12, 2010 5:00 pm UTC

I don't t think it would be useful. It would be almost impossible to hit a point target due to the amount of distance the bullet has to travel. For these situations, they have been experimenting with grenade launchers where the grenade detonates after a set distance. That's a much more effective tool.
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Re: Bullet drop

Postby gorcee » Tue Oct 12, 2010 7:15 pm UTC

Not to mention that the report from the shot would reach the target well before the shot itself did.

*BANG*

"Ok, guess I should move"

12 seconds later... *bullet hits the floor*

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Re: Bullet drop

Postby nehpest » Tue Oct 12, 2010 7:31 pm UTC

To echo what's been said above, this system would be cripplingly impractical.

If you watch the Discovery Channel, you might remember seeing the XM307 from Future Weapons. This weapon system uses a timer to detonate a smart round at a predetermined distance, which is determined via laser measurements. The whole thing is computerized.

Edit: I fail at capitalization.
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folmerveeman
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Re: Bullet drop

Postby folmerveeman » Tue Oct 12, 2010 7:57 pm UTC

I don't know.. Future Weapons always seems a bit propaganda-ish to me, not to be be a conspiracist though.. But if all our weapons are that grand, why do we still struggle against terrorists?

Also it only features weapons from the 'western world'. I don't believe we have all the weaponry portrayed in that show, or at least not in working order.

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Re: Bullet drop

Postby Thesh » Tue Oct 12, 2010 8:09 pm UTC

folmerveeman wrote:I don't know.. Future Weapons always seems a bit propaganda-ish to me, not to be be a conspiracist though.. But if all our weapons are that grand, why do we still struggle against terrorists?

Also it only features weapons from the 'western world'. I don't believe we have all the weaponry portrayed in that show, or at least not in working order.


It's called future weapons, not weapons that are currently in place today (although, they may be, I don't watch the show). I'm guessing the reason why they only show US weapons is probably two fold. One, because they don't have the budget to travel all over the world. Two, because the US spends a lot of money on developing all sorts of crazy weapon ideas. Also, the XM307 project was canceled, but the XM25 is currently in field testing.

http://en.wikipedia.org/wiki/XM25_Indiv ... pon_System

Also, all these cool weapons don't protect us from IEDs, which is the leading killer of troops in both Iraq and Afghanistan.
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Re: Bullet drop

Postby jmorgan3 » Tue Oct 12, 2010 8:24 pm UTC

Thesh wrote:Also, all these cool weapons don't protect us from IEDs, which is the leading killer of troops in both Iraq and Afghanistan.

OT: Here's some cool stuff that will, though:
http://kitup.military.com/2010/10/natur ... flame.html
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Re: Bullet drop

Postby Sockmonkey » Tue Oct 12, 2010 9:16 pm UTC

I hate the host of that show. He acts like the Steve Irwin of guns. I'd pay real money if he would just shut up or at least tone down the forced intensity narration.
In any case, you can't aim a rifle by hand accurately enough to pull off a ballistic arc like that. Just use your classic grenade launcher.

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Re: Bullet drop

Postby Mr_Rose » Tue Oct 12, 2010 10:59 pm UTC

folmerveeman wrote:I don't know.. Future Weapons always seems a bit propaganda-ish to me, not to be be a conspiracist though.. But if all our weapons are that grand, why do we still struggle against terrorists?

Also it only features weapons from the 'western world'. I don't believe we have all the weaponry portrayed in that show, or at least not in working order.

Regarding your first point: Because fancy weapons don't win wars; appropriate strategy & tactics, and trained soldiers do. And, to be totally frank, not a very great deal of those were deployed to either Iraq or Afghanistan...

As for your second: Not all of the weapons there are ever intended for soldiers. The HIWS, for example, is a proof-of-concept "hey, if we can turn an 80mm mortar into a shoulder-fired weapon, imagine what we could do for a rifle?" type deal, rather than an actual thing you'd ever fire at an enemy.
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Eebster the Great
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Re: Bullet drop

Postby Eebster the Great » Wed Oct 13, 2010 12:36 am UTC

Besides, Americans don't "struggle with terrorists" in terms of relative deaths, just absolute deaths. Many, many more Afghan soldiers and terrorists have died than Americans despite them having "home court advantage" so to speak.

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Re: Bullet drop

Postby ectoid » Wed Oct 13, 2010 1:09 am UTC

Perhaps as a U.S. Marine I can offer some insight into some of these issues(though perhaps not a lot of insight, as it were).

First, for the OP: a variable drop bullet, though technically plausible, is not feasible for the military. This is primarily due to several reasons listed above, which I will reiterate for posterity.

1)Logistics - We've been fielding weapons to our grunts in a very limited variety of calibers for a very long time. The primary caliber utilized by the average Marine or Soldier is the 5.56, with 7.62 and .50 machine guns. These are the common weapons that you will find anywhere in the military. At the time when I exited active duty, the standard issue for a Marine was the M16A4, though there were some being issued the M4 carbine. Add on handguns for Staff NCOs, Officers, and selected billets, the occasional shotgun and sniper rifles, and it is plain to see that there is not a large amount of variation in weapon calibers. This is a good thing, because it means that ammunition becomes cheap and readily available(i.e, in a firefight you don't want to ask your buddy for a spare magazine and find out he is shooting something entirely different than you). So logistics plays a big role in the equation.

2) Training - This goes along with logistics, really, but the introduction of a special weapon requiring special tactics and techniques for utilization increases training demands. Who gets these special bullets? Just snipers? Regular infantrymen? These complications can drastically change things like the time it takes to adequately train a serviceman.

3) As stated by someone else above, it is much easier to just shoot through the material, throw a grenade, or utilize an existing form of indirect fire(mortars, artillery, the M203 grenade launcher(or its predecessor the M79). These are more cost effective and practical methods. Though the .50 sniper rifle isn't the most commonly deployed, it does see action, and it will punch a hole through lots of materials an enemy might seek cover behind. And that's with normal ammunition. Google for the different types of .50 caliber ammunition and you'll find some interesting ones(SLAP rounds :D)

As well, though a bullet with variable drop is infeasible, a similar concept IS employed with machine guns(and arrows...). Obviously any bullet is going to follow a ballistic trajectory that will be affected by many known factors that don't need to be discussed(I guess they could be, but I'm just moving to the next point). Due to the ballistic trajectory, there is a 'beaten zone' at the end where the rounds impact the ground. This is exploitable to the same advantage as your idea of a variable drop bullet. Some quick googling for related terms should give military training manuals and such explaining the matter if there is any confusion from my lack of eloquence.

Spoilered for off-topic:
Spoiler:
And in reply to Mr_Rose, your comment on the training of our servicemen and women is baseless. Though I could point out the failings of the Army(rivalry and all), and a noticeable drop in the quality of recruits entering the service(Maybe quality isn't the word to use, but it seems to fit best. There are a large number of kids going in that have never been in a fight, never been yelled at, and can't handle the stresses of service. This is largely an issue with our society. Basic Human Decency and coddling breeds weak and ineffective children that should not be introduced into a warrior culture), we currently are in possession of an excellent fighting force. Disregarding the turds that will always crop up looking for a free ride, today's Marine Corps is one of the most intelligent, well trained, and effective fighting organizations around(I will go ahead and cut out any criticism such as "well the IDF or ROK Marines are better blahblahblah" by saying that there are many other formidable forces in the world, and having trained with the ROK Marines, I have the utmost respect for them. The point of this rant is not to deny the skills or abilities of any other force, not to bluster and toot a horn for the Corps, but instead to put to rest the fallacy that our current servicemen and women are not up to snuff.)

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Re: Bullet drop

Postby Mr_Rose » Wed Oct 13, 2010 11:01 am UTC

Spoilered for off-topic:
Spoiler:
I find it amusing that you think I was referring explicitly or exclusively to American service personnel. Also, I wasn't aware that the marines were the only US troops deployed in either of the mentioned conflicts...
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Re: Bullet drop

Postby folmerveeman » Wed Oct 13, 2010 1:47 pm UTC

ectoid wrote:Snip


Wow, thanks for your reply, it was really insightful! :)

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Re: Bullet drop

Postby ectoid » Wed Oct 13, 2010 2:30 pm UTC

Here's an interesting one for the topic of snipers and whatnot: the world record for longest confirmed kill by sniper fire is now owned by a Brit, at ~2740 meters, or ~1.5 miles. This figure was from a quick google, so it may be inaccurate.

To elaborate on something pertinent to the OP, a quick google of .50 demonstrations will show why such methods of indirect fire are generally unnecessary. For anything that that won't punch through, the M203 grenade launcher has an effective range vs. a point target(say, a person) of 150 meters. Against an area target(several people, big things, etc.), you can effectively engage at 350 meters. When fired at these ranges, the trajectory of the grenade will accomplish through simple means what you seek to accomplish through complexity.

:D


This is the last I will say on these matters, and any follow up discussion should be constrained to PMs. I guess my first several posts on a forum I've been lurking on really shouldn't contain so much vitriol...

And also maybe should have started in PMs, at least inasmuch as they and the replies to them have dragged this well off topic. - gmalivuk

Spoiler:
I am sorry for any muddying I may have done to the waters by not explicitly prefacing my argument with disclaimers, such as the following.

As a U.S. Marine, I can only give insight into the training, weapons, lifestyle, general efficacy, operational tactics, or any other category of discussion from the viewpoint of a Marine. Certain categories may be extrapolated to the other branches of service(weapons for instance, are fairly standard, though the other branches may have a larger number of M4s instead of M16s). Others are going to be completely incompatible(quality of life in the Air Force, Army and Navy? Pretty good. In the Marine Corps? Heh...).

Perhaps this disclaimer would have negated the need for a statement such as your last, Mr_Rose.

Additionally, there did not need to be an explicit reference to American personnel, as in the conflicts you pointed out are largely American conflicts(a look at the breakdown of coalition forces deployed will support this statement. And as above, I am not negating or belittling any other nations contributions, as the burdens of war are born heavily by all who participate). In this light, it would be appropriate for you to explicitly state what forces were being discussed, unless American forces was implied(which I believe you did imply, and then made this statement to cover your rear).

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Re: Bullet drop

Postby Mr_Rose » Wed Oct 13, 2010 4:04 pm UTC

Spoilered for off-topic:
Spoiler:
You're right, trained was the wrong word. Perhaps experienced would be better? Mostly though, I was talking about the first half of the sentence, the strategy & tactics bit. Of course, I'm one of those silly people that thinks the strategy failed the moment someone came up with deploying an invasion force as a way to win over the other side in what is basically an ideological conflict regarding resource distribution.

EDIT: Actually, I think I was right the first time. As a Marine, how much training do you get in "how to be an army of occupation?" Because whilst the initial invasion was performed with precision and fortitude, the moment the coalition "won" (declared itself the winner without bothering to accept the enemy's forfeit more like) it stopped being an attack on defined military targets and became a force of occupation, defending against sporadic attacks from non-military partisans.
Microevolution is a term — when used by creationists — that is the evolutionary equivalent of the belief that the mechanism you use to walk from your bedroom to the kitchen is insufficient to get you from New York to Los Angeles.

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Re: Bullet drop

Postby ectoid » Wed Oct 13, 2010 8:38 pm UTC

Spoilered for off-topic:
Spoiler:
I came out of lurking to dispel a fallacious statement. I believe that despite your backtracking I have been successful. I did not, however, come to discuss issues such as politics or facets of the conflicts in general. As someone who has personally bore those burdens, and has brothers in arms that are still bearing it, this is a topic that I have a hard time trying to discuss with people over the 'tubes. That is not to say that I lack a developed viewpoint, or anything to that nature, just that it is a fruitless endeavor to try to attempt.

With that said I guess I will take the bait one last time and leave the discussion with this.

You are correct in the affirmation that Marines aren't an occupying force. However, as true as this statement is, it neglects the agility of the Marine Corps in re-posturing itself to take on new missions. This is something that has grown from the Marine Corps having to defend itself against dissolution through the years - there have been many attempts to merge the Marine Corps with the Army, simply disband it, etc. Our strategy for dealing with this is adapting to any mission that arises, whilst the Army is slow to adapt to new mission types. There are issues that arise when the Corps takes on a mission such as occupation, but they're not primarily issues of training or experience, but instead numbers. Numbers of troops, logistical supplies, and the budget are all limited(when I joined we numbered ~198,000. Over several years our strength grew to ~243,000. This is in contrast to the Army's ~1 million.).

As an example of the Marine Corps' re-posturing to take one new roles I will provide a comparison between the two latest hand-to-hand combat systems employed by the Corps. The previous system, known as the LINE system, was structured almost entirely around deadly force. Most techniques were concluded with the user stomping the skull of his opponent. The new system, known as MCMAP, has many benefits, one of which being its embrace of the full spectrum of violence, from less than lethal to lethal. The provides Marines with an effective tool for engaging new missions, such as peacekeeping, police missions, and humanitarian missions where you aren't always going to want to go straight to stomping skulls.

As a Marine, I was trained to improvise, adapt, and overcome so that I can fulfill any role assigned to me, whether it be humanitarian, peacekeeping, occupation, police action, or simply kicking in doors. To ride your tangent on Marines not being trained to be an 'army of occupation' further, we also aren't specifically trained to provide humanitarian relief, but I've done that one as well in Southeast Asia. You don't hear about that stuff as much, because it isn't a divisive issue such as our current conflicts, so it doesn't really afford people's attention for as long.

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Re: Bullet drop

Postby gmalivuk » Fri Oct 15, 2010 7:01 pm UTC

Please try to keep the whole discussion more on-topic.
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