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Discussion > Writing Class > Guns, Bombs and Sundry Other Things Like That

Guns, Bombs and Sundry Other Things Like That

Semirrahge (November 4th, 2002, 2:00 am)

My range of technical knowledge is great, but not expert. Other things I know about, but not enough to answer questions accurately.

However, because I own guns, shoot regularily, and sell ammunition, I know more about guns than your average guy who merely knows that when you pull the trigger it fires and that they are cool.

So. If anyone has any questions about things they saw in a movie, game, or anime, ask me - If I can't give you an answer straight off, I can find it out.

Or, if you'd simply like to know a basic overview of how a gun works; the differences between revolvers, automatics, and machine guns; or how bullets work in killing or penetrating things... just let me know and I'll try and work up a small article.

For now, I'd like to tackle automobile window glass. The front and rear windows are constructed of two laminated safety glass plates, sandwiching a plastic sheet. The side windows are simply made of one sheet of safety glass.

For those of you who don't know, safety glass is a special type of glass that (and I'm not sure of the specifics here), has regular (as opposed to irregular) crystalline fault lines. I'm not sure if you call them fault lines, but basically what it means is if you break a sheet of ordinary glass, you get nasty shards. If you break safety glass, you get little squares.

Now, when you shoot a single sheet of safety glass, it goes all to smithereens. The different crystalline structure causes a reduction in strength once damaged, and the stuff just falls apart.

However, and this gets complex, and I can't explain all the physics, but; Glass in ANY form is VERY hard. Because of this hardness, and because of the angles of the winshields, it's actually very hard to shoot through window glass in a car.

Generally, and this all depends on caliber/weight/speed of bullet, a bullet that intersects the winshield at an angle less than 70 degrees will just deflect. You might get some form of damage done to the window, but the bullet would NOT enter the cabin, and - this is the real kicker - the window would not crumble into your lap.

I've shot at window glass using .45 ACP (automatic, not revolver .45) caliber, and know first hand that this is true. In my case, I got a 3-4 inch long gouge in the winshield. I don't remember any cracking taking place.

However, lets say that your bullet weight/caliber/speed ratio is good, and you have an angle that is greater than 70 degrees, say, 85, and you get penetration. The window is going to remain intact. You might get some spiderwebbing effect, but the majority of the damage is going to be in the spot where the bullet hit.

As another example, one day I was riding with a friend in his truck when a bolt or rock (or something) flew off a passing semi (no, not me!) and crunched into the winshield in front of my head (passenger side). Whatever it was did not come through, but tiny glass shardlets sprayed EVERYWHERE inside the cabin, and the window remained intact.

As I remember, there was minor spiderwebbing over the rest of the winshield, but aside from the crunched-up bit where the object had hit, it was ok.

My point in saying all this is that those movies that show one bullet shattering a front/rear window is bull. I don't know how many bullet holes a winshield can take, but it is a LOT more than one measly 9mm slug.

Ah! Good to know.

Narainsbrain (November 4th, 2002, 6:52 am)

Yeah, just like windows burst into spiderwebs with just a tiny hole in the middle when shot at. To really shatter a whole piece of glass into tiny shards requires something of significant size - like a rock. I'm not speaking from presonal experience, of course.

I WOULD appreciate a little writeup explaining the diferent kinds of guns, Semi, especially since I can't tell a pistol from a rifle.

"...a passing semi (no, not me!)" Hahaha! Funny!

One last thing: I know an open lump of explosive is pretty useless by itself - confining it to explode in one direction and/or drive a solid object makes a much more powerful weapon/tool. I'm curious though, if you just have a lump of explosive lying around on the floor, and you set if off (remotely, if you're not a fool), how much damage does it do, and till how far?

Pretty pointless question, eh? Well, you asked. =)

Useful stuff

cruise (November 5th, 2002, 9:07 pm)

Most of the basics I know already...working on three first-person shooter mods has taught me more about guns than I ever thought I'd want to know, but a good reference person is never a bad thing :P

Ok, well...

Semirrahge (November 6th, 2002, 6:05 pm)

Again, generalizing physics - esp. advanced high-energy/velocity stuff, since even basic physics math is beyond me - is difficult.

What kind of explosive, how much, what type of floor surface, what's the burn rate, etc... Also, remember that an explosion only happens because:

Material burns. Burning process causes breakdown into waste gases. The gases use more volumetric area, and expand. The explosion happens when the gases expand at a rate greater than the containers walls will move or break down. Eventually the walls rupture, causing instant pressure release. Explosion.

If you have a mound of powder (gunpowder) on the floor and light it, nothing will explode. The burn rate is not high enough. You'll end up with a lot of smoke and a scorched mark. TNT (Dynamite, or Trinitrotoluine(I think that's how you spell it)) is a big version of the firecrackers used on the American Independence Day celebrations. Plastic explosive is it's own container, and depending how you lay it, it can be a shaped charge.

If you took a block of C-4(Composition 4; R.D.X. or Cyclonite), say, a 1/2lbs rectangle, and detonated it inside a cement slab house, 20 feet by 30 feet (Pretty much a standard size where I live), it would probably blow the whole house down.

Again, this is knowledge taken aside from math. :) I could be all washed up, but C-4 is VERY mean stuff. You don't want to be ANYWHERE near a block of the stuff when you detonate it.

And, to further complicate matters, a nuclear explosion is totally different. Sorta. :)

Anyhow, pointless questions are fine. Things that go boom are one of my favorite topics. :)

As for a SUPER-BASIC overview of guns...

- - -

The two basic types of personal (I.E. guns you can carry and operate with relative ease. A minigun (rotary autocannon) is theoretically human-portable, but because of certain technical issues, the gun featured in Predator is not realistic) guns are Rifles/Long Guns; and Pistols/Hand Guns. A rifle is normally designed to be fired from the shoulder, and requires two hands to operate properly. There are exeptions to this, like a machine gun fired from the hip, but I can't think of any reason to shoot a long gun with one hand. Oh, and on a side note, the term "Rifle" originally came from the "riflings", or the spiral ridges/grooves on the inside of the barrel; designed to impart spin on the slug as it traversed the length, and thus giving the projectile gyroscopic stabilisation once it left the guiding walls of the barrel and thereby increasing accuracy, and thereby increasing the range of the weapon. Rifling was a major technological breakthrough, and initially it was only available on long guns. The term became synonymous with the long gun, and it stuck.

A handgun, or pistol, is smaller, and is specifically designed to be used with one hand. "Machine Pistols", or fully-automatic handguns, sometimes have a foregrip so you can use two hands to help compensate for increased recoil. The pistol also has a smaller barrel, and the bullet size/powder charge is less. There are exceptions to this, of course, notably during the "Old West" period of American history, when several rifles fired the same ammunition as pistols. Even today, one can find some of that crossover in modern weapons, although to a much lesser extent.

Also, the barrel length is not always a given, as there are many guns, esp. in the larger calibers (.45 LC; .454 Casuul; .50 AE) that have barrels approaching 12". Also keep in mind that machine pistols, like the Heckler and Koch MP5 PDW, often look like a cut-down rifle, and often are.

There are variations on the Pistol design, as well. You will find Revolvers, or "wheel-guns" as they are sometimes called; and Automatics. The differences in design and operation are drastic, to to point that revolvers and autos (normally) have to use different ammunition.

I will do my best without the assistance of diagrams, but please ask for clarification on things that are unclear.

First I suppose I had better point out the differences between "Double-Action" and "Single-Action" mechanisms. A "Double-Action" weapon will cock the hammer from a down position, and drop it again, simply by pulling the trigger.

A "Single-Action" weapon must be put into "battery" - or, ready-to-fire-mode, so to speak - manually; normally by pulling back the hammer with your thumb. If the hammer is down, I.E. resting against the back of the chamber, pulling the trigger will do nothing.

A double action gun can be fired like a single action, and it's often best to do that, because it can reduce the distance the trigger has to travel by 3/4.

The revolver is traditionally a single action gun, but modern revolvers, especially the new hammerless(not really, but they are called that because a shroud covers the entire hammer mechanism) guns are double action or even double action only.

The essential operation design, however, has remained unchanged since the mid-1800's; a revolving cylinder functions both as a magazine to store the ammunition and as a firing chamber.

When the gun is put into battery, either by cocking the hammer manually or by pulling the trigger, the entire cylinder rotates, aligns a new round with the firing pin and barrel, and locks into place so the cylinder won't move under the pressures caused by firing.

I think it needs to be pointed out that when you fire a double action only, or DAO, gun, there is not a stopping point where the hammer locks into place. You just pull the trigger all the way back, the hammer comes back, and then trips and falls.

The automatics, on the other hand, are much more complicated. The whole mechanism relies on the principle that every action has an equal and opposite reation for the entire process or operation. These guns use a magazine - often and incorrectly called a "clip" - to hold the ammunition before firing.

Personally, the mechanism of the autoloading handgun is amazing. I'll do my best to describe its operation in a manner that's easy to understand, but I wish I had some diagrams. :)

Where to start? I guess to say that when the gun fires, the recoil knocks the slide back, ejecting the spent cartridge, recocking the hammer, loading a new round and locking it into place.

Not all autos have an external hammer. Those that follow the design of the Glock, for example, use a spring mechanism to operate the firing pin in place of a hammer, but the essential function is the same - aside from the fact that those guns are DAO. I'll be using the Glock mechanism for my example, but keep in mind that there are slight variations to the operation of the different designs of guns.

The first thing that happens when you pull the trigger is the firing pin detonating the primer, which causes the main powder charge to go, and push the slug down the barrel. This causes gas pressure, of course, which rapidly builds up to overcome the return spring and knock the slide back. This, in turn, causes the barrel itself to drop down slightly (about 1/8" {~2mm} in the one I have in front of me), pulling the spent cartridge down off the breech face by that much, and this drop also allows the slide to move back (When the slide is at its "home" or ready to fire position, the barrel is directly in line with the breech face - this is what the bottom of the cartridge butts up against, and the firing pin is in the exact middle - and the forward pressure of the return spring pushes the barrel up, which locks the whole mechanism into battery. If the gun is not "in battery", I.E. the breech disengaged from the chamber, it won't fire. This lockup is not very strong, but if you grab the slide and try to move it by hand you will notice a small amount of rearward motion is possible before the barrel disengages.). As the slide reaches the end of its travel, a pin kicks the spent cartridge free, clearing the way for the next round. The slide having lost its rearward momentum, the return spring now has the freedom to push it back forwards. At this point - with the slide all the way back (nearly 1 1/2" on this gun) - the hole in the slide is directly over the top of the magazine, which has a spring in the bottom that pushes the new rounds against two curved retainers. The shells can only exit the magazine in a forward motion because of these retaining clips, and as the slide begins its return, there is a hook (not really a hook shape, but I can't think of a better term. It's more like a stud or a plate.) that engages the rim of the cartridge, pushing it along. As the cartridge leaves the magazine, the bullet nose hits a feed ramp on the bottom of the chamber (part of the barrel, which, remember, is still at a slight downward angle) and is pushed into position in a smooth motion. The final step is to return fully and engage the battery, which also aligns the trigger mechanism with the firing pin trip.

Suddenly I feel very tired. :) I think I'll save any more details, and the section on rifles, for another day.

Heh. No wonder. Word gives this article 3 full pages, with 1,600 words - including this sentence.

Ok, well...

Eldritch (November 7th, 2002, 1:50 am)

Oh... Uhm...I don't know too much about giuns, except I've used them once in a while...Rifles or long guns are my personal favorites. Added accuracy is always good :D It's fun shooting toy soldiers... Anyway, weapons with AP rounds tend to leave "cleaner" holes than other weapons. API(armor piercing incendiary) are amonst the most powerful(those are the ones usually used for war jets and gunships), seeing as they pierce and then explode inside, creating a devastating effect.Flat or round rounds have a larger area effect, but smaller piercing ability... That's about all I know about ammo. Oh, BTW Semi, is it possible to create a low-heat gun by the use of magnetic-propulsion to fire off the bullet? I think it's tough, but I'm sure it's "makeable" . If you can , please explain why or why not.

cruise (November 7th, 2002, 6:38 pm)

They already exist.

The "barrel" doubles as the magazine. Each slug is queued up within it, and is acclerted out in turn by electro-magnetic means.

Because there is no cocking/rechambering required, and no moving parts except the slug itself, the fire rate is insane. I have seen the video clips, where their larger versions, which fire shells about the size of a standard grenade canister, eject each shell at normal bullet velocities with only about a foot or so gap bewteen them.

It works out in the order of hundreds of thousands of rounds per minute. Which is pretty damn scary, really.


Eldritch (November 7th, 2002, 9:19 pm)

Damn... Then why aren't those bastards up in production and replacing regular guns?!

cruise (November 8th, 2002, 11:13 pm)

Patented and carefully licensed tech. Plus it's still being in the "testing" phase, I believe.

I can't remember the website now, unfortunately, or else I'd point you in its direction.

Oh, ok!

Eldritch (November 9th, 2002, 1:45 am)

If you do remember, please gimme the link... I'd like to see that in action =D

Guns Pt. 2

Semirrahge (November 11th, 2002, 9:19 am)

But, first things first...

Cruise, where'd you hear about this? I've never heard of that... The only thing similar is the, um... Hellstorm weapons system, and it runs off caseless ammo.

Eldritch, another reason you don't see the gun is COST. Even with mass-production, the development costs would have been ASTRONOMICAL... This gun, if ever sold, will cost a fortune. Besides, who wants a gun you have to throw away after you use it? Only the military.

Another thing you might have been curious about is the Electromagnetic Propulsion guns, i.e. Rail and Coil guns. These guns work on the same basic principle, which is to use electromagnets to hurl the projectile at high velocities. The problems are: TREMENDOUS power usage(and I do mean tremendous. The bank of capacitors needed to run the thing cost more than the gun and ammo combined), the Rail method needs new rails every few shots, and both have the problem of hurling the projectile so fast that it burns up.

The currect EMP-fired projectile, last I heard, was some sort of ferrous metal embedded in high-temp ceramic. Also, I seem to recall them doing it the other way round, in the Coil guns, and the ferrous Sabot would just fall off after leaving the barrel.

Last time I was here I posted about Pistols, now I'm going to tackle Rifles.

Because most modern guns all use the same principles, whether auto-loading or single-shot, I'll just focus on the mechanism used in the AK-47 as my example.

AS most of you may know, the AK-47 is the mainstay assault rifle for all third-world countries. Its simple, robust design makes it well suited for harsh-condition, low-maintenance environments.

The design is essentially the same as the automatic pistol, with a few changes. Of course. :)

When you pull the trigger, the hammer trips and falls onto the end of the bolt, hitting the firing pin and detonating the round. Something I should point out here is the fact that because the breech mechanism in Rifles locks into battery so firmly, they use a blowback rod instead of simply relying on recoil alone to shoot the bolt back. The gas buildup inside the barrel leaks back up a gas port near the end of the barrel (it's put at the end because it keeps the bullet velocity up), and helps to unlock the bolt and slide it back.

The bolt ejects in the same way, the bottom of the spent cartridge hits a metal pin and is tossed out the ejection port. The bolt catches the top of the hammer which knocks it back and locks it into the trigger mechanism, reaches the end of its travel and begins the return trip. Here, the bolt catches the bottom of the round and pulls it by the use of feed ramps onto the breech face. Here the pistol similarity ends, because as the cartridge slides into the chamber, the bolt hits guides and rotates into place. This is unbelivably cool to me. :)

I'm getting tired again, but I want to comment a little on the difference between Assault Rifles and Battle Rifles. An Assault Rifle is a short, lightweight gun, very similar to a carbine in length that fires small caliber ammunition. It is designed to be easy to maintain, and equally easy to carry and operate by one person. Guns in this category are the M-16 and AK-47, among others. The short barrel length reduces range and accuracy, and the loose lockup reduces accuracy further. The Battle Rifle, on the other hand, is heavy (weighing up to 3 TIMES what an Assault Rifle does), more accurate, and often designed for an emplacement and/or crew operation. The recoil is greater, as the barrels are longer and the caliber larger, which also means that the ammo weighs more. Guns in this category are the FN Minimi/M-60/SAW; H&K G3; and the FN FAL.

On a closing note, Sniper-grade weapons use the largest calibers (normally NATO rounds, but since military snipers are SpecOps then anything goes) and are 99% of the time bolt-action. I don't have the time to get into why bolt-actions are used, other than the fact that they are more accurate, and I don't know that I could explain why they are more accurate anyhow. Just so you know. :)

Next time, I'll finish up with ammo types.

Oh, and if I can find me an artist at DA, I'll make this an official article. Cool, eh?

Guns Pt. 2

Eldritch (November 12th, 2002, 11:05 pm)

Yes :D Anyway...I wouldn't consider de m-16 all that short... Shorter than a battle rifle, but not as small as an AK-47. Oh, and, tackle machine guns...Those are the coolest.

Wow, Semi!

Narainsbrain (December 5th, 2002, 4:51 am)

Now that's one heck of an article. Thanks, though you lost me in parts, mostly since I have ony a very vague picture in my head. But I'm bookmarking this for future reference =)

Btw, I'm an artist at dA! ;) but if you're looking for pictures of guns to be made, sorry, can't help you there. But it sure would be incredibly cool to make this a full-fledged article!

And sorry for being away all this while.


Semirrahge (December 9th, 2002, 4:41 am)

I've been gone longer, I think. :)

Anyhow, what parts did I lose you on? I'm very good at descriptions. :P Style is my only strong point...

Yeah. If I had more sway at DA, I would go asking folks for help... But, I think I have 500 pageviews in nearly a year. That's a real and gen-u-wine nobody. Ah well.

At least I'm known and loved here. :P

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