Tags:
  1. Killer300
    Offline

    Killer300 Active Member

    Joined:
    May 1, 2011
    Messages:
    1,064
    Likes Received:
    37

    Firearm questions

    Discussion in 'Research' started by Killer300, May 2, 2011.

    1. Okay, if dozens of guns were to fire within a room the size of the average bar, would everyone in experience severe ear damage from the immense noise? The guns include two .45s, three 12 guage shotgun, four 9mm machine pistols, and three assault rifles chambered in 7.62mm. None of the weapons are suppressed, and no one is wearing ear protection.
    2. Does it take significantly less time to pull the trigger on a hair trigger than a normal one?
    3. If guns are fired in a closed room, i.e. the door and windows are closed, would the sound still be heard outside? The number and calibar of firearms is in the first question.

    I'm wondering all of this in relation to the beginning of a story involving firearms.
     
  2. Lothgar
    Offline

    Lothgar Contributing Member

    Joined:
    Aug 31, 2010
    Messages:
    417
    Likes Received:
    37
    Damage, doubtful, but their ears would ring for a while afterwards.

    Significantly, no, fraction of a second difference maybe. A hair trigger is just easier to pull (for example 5 lbs of pull pressure instead of 12 lbs of pull pressure).

    It would be heard all the way down the street, but the sound would be dulled, muffled, but still heard.
     
    1 person likes this.
  3. Killer300
    Offline

    Killer300 Active Member

    Joined:
    May 1, 2011
    Messages:
    1,064
    Likes Received:
    37
    Thanks, and I hope you can help me with these questions too.
    1. In the average sized bar, would there be any cover that could withstand assault rifle rounds like 7.62mm and shotgun rounds? This is important because otherwise this fight I think would have no survivors.
    2. How likely are rifle rounds to ricochet in such a room? Same calibers as with previous question.
     
  4. TWErvin2
    Offline

    TWErvin2 Contributing Member Contributor

    Joined:
    Nov 30, 2006
    Messages:
    2,529
    Likes Received:
    561
    Location:
    Ohio, USA
    What Lothgar said.

    The structure of the room, whether there is any carpeting vs. tile floors, the type of ceiling (foam drop or plaster for example) would make a difference, but nobody would be hearing much right away afterwards--those still standing. Permanent, not likely, but of course if someone had the muzzle near an ear for multiple shots? But that'd be an odd situation.
     
  5. Cogito
    Offline

    Cogito Former Mod, Retired Supporter Contributor

    Joined:
    May 19, 2007
    Messages:
    35,935
    Likes Received:
    2,043
    Location:
    Massachusetts, USA
    Also note that two weapons of the same caliber can have different propellent loadings, which will affect the magnitude of each report. Barrel design and length will also affect the rate of expansion of the propellent gases, and the direction, and that will affect the sound output and directionality. Also, the projectile's velocity as it leaves the barrel affects the shock wave produced.
     
  6. Porcupine
    Offline

    Porcupine Contributing Member

    Joined:
    Feb 13, 2011
    Messages:
    346
    Likes Received:
    21
    Location:
    Frankfurt, Germany
    Re 1: Depends what material the bar is made of. If it happens to be made or armour plate, yeah. Otherwise, not really. Though even a solid wooden bar with two thick planks spaced far enough apart could potentially stop (at the second plank) shot from a shotgun (but perhaps not a slug). Nothing will stop the assault rifle rounds, at least I certainly wouldn't want to take such a chance in real life. Any brick or better reinforced concrete walls in your bar?

    Remember, however, that "cover" is both visual and physical. In order not to be hit, you can be either behind a physical barrier which stops the bullets, or you can just be hidden, and hope the assailant aims in the wrong place. In a gunfight, even a regular table thrown over as a shield provides some cover, since your opponent does not know exactly where you are behind that table, and has to guess. If you're flat on your belly, you might have a chance of survival.

    Re 2: Pretty likely to ricochet around quite a lot.

    :D Lothgar is quite right. The din will be heard a mile away or more, and anybody with some exposure to firearms will know what is going on, too.
     
    1 person likes this.
  7. Jayyy1014
    Offline

    Jayyy1014 Jerrica Contributor

    Joined:
    Apr 9, 2011
    Messages:
    1,363
    Likes Received:
    46
    Location:
    United States
    Good luck with the story, If it is firearm involved, I'm bound to read it :)
     
  8. Killer300
    Offline

    Killer300 Active Member

    Joined:
    May 1, 2011
    Messages:
    1,064
    Likes Received:
    37
    Thanks guys, and it will come soon. This scene actually is right off the bat, and I'm not sure what the bar is made of. I do have a feeling though that there will only be one survivor. And, that's only because that character has made preparations. This is sort of a begins at the end style story.

    One question I do have is this. Can a bulletproof vest survive two entire magazines from assault rifles chambered in 7.62mm? It would help if same vest can survive all the other guns present, which have been shown in previous posts. Assume the vest has to be hidden.
     
  9. TWErvin2
    Offline

    TWErvin2 Contributing Member Contributor

    Joined:
    Nov 30, 2006
    Messages:
    2,529
    Likes Received:
    561
    Location:
    Ohio, USA
    Even before that is considered, would all the rounds shot at the individual actually hit him only in the vest?

    How many rounds from an assult rifle? Shotgun blasts (unless they're using something like deer slugs) won't be limited to a vest at any reasonable distance. And if someone keeps getting shot in the chest, knocked down and survives, wouldn't someone logically shoot him in the legs or head/face?

    I'm not an expert in body armor, so I can only answer in general terms.
    What type of vest? Some are of woven/laminated layers, others add metallic plates, etc. Most are effective against small calibar pistols and shotguns, but that doesn't mean the fellow won't be knocked around, bruised and injured.
     
  10. Killer300
    Offline

    Killer300 Active Member

    Joined:
    May 1, 2011
    Messages:
    1,064
    Likes Received:
    37
    This is more the vest gets hit repeatedly because a lot of people are firing, therefore the person is also getting hit by richoeting bullets and by people just aiming in their general direction. The entire fight takes like, a single minute. It's a furious close quarters battle that feels a lot longer to those in it than it actually is.
     
  11. Porcupine
    Offline

    Porcupine Contributing Member

    Joined:
    Feb 13, 2011
    Messages:
    346
    Likes Received:
    21
    Location:
    Frankfurt, Germany
    Military body armour, as far as I am aware, can not withstand assault rifle rounds, and especially not in 7.62 mm. The vests can't, and the helmets can't either. They are designed to protect primarily from shrapnel and ricochets.

    If your character is wearing a very good vest, it will stop the shotgun blasts, and the 9mm rounds almost for sure, though he will get the wind knocked out of him, and potentially faint from shock. Stopping the .45 is doubtful, but possible, and the 7.62 mm will just go clean through.

    The only way your character could stop the assault rifle rounds is if he is literally wearing armour plate. Don't think that sounds too realistic for your scenario.

    May I ask what the assault rifles are doing there in the first place? They are very "cool" as weapons go, but neither criminals nor other shadowy (urban) characters hardly ever use them because they are bulky and almost impossible to conceal, and you usually don't need the power or the range. Think about where they are being used here in your story - in a bar, maximum range about 10 m. Assault rifles are intended to be used at ranges of 50 to 600 m. There would be no need to bring them.
     
  12. Killer300
    Offline

    Killer300 Active Member

    Joined:
    May 1, 2011
    Messages:
    1,064
    Likes Received:
    37
    Well, I can't say too much, but this is in a place where you need LOTS of firepower. Police? Nonexistent, beyond certain types of crimes that would humilate public officials like drug dealing and certain surgeries(latter is in story and I can't give it away so don't ask.)
    Therefore, if you want to survive every day, you need more than handguns. You need POWERFUL main weapons. The people carrying SMGs are actually carrying their side weapons really, and the two guys with pistols were caught off guard. When they are traveling for long distances, or going to places of danger, they carry bigger guns. The person with a shotgun has a semi-automatic shotgun that is magazine fed, and they don't leave the city. Otherwise, they would get an assault rifle. Most of the criminals in this place have to have at least two guns, one for serious combat, the other for backup.
    Some people will also carry full blown machine guns everywhere they go, like an MG3, as part of group so they can get paid for extra protection. This is like the Old West in that you have to be able to protect yourself, except here you have to be to do so against threats that range from normal criminals, to cults armed with military hardware on the level of the U.S. at times.
    So, that's why they have assault rifles. Now, they have them in the bar because they are waiting for an assignment, and here you can carry guns wherever you want except government structures. So, if someone walked into the bar carrying a minigun, which is actually possible for some people but I can't talk about it here, that would perfectly cool.
     
  13. Lothgar
    Offline

    Lothgar Contributing Member

    Joined:
    Aug 31, 2010
    Messages:
    417
    Likes Received:
    37
    Only in the movies...or an act of divine will.

    Most body armor vests are rated for various types of handgun rounds and are intended for security/police protection.

    Most military body armor is bigger, bulkier, heavier, hotter, rated to stop artillery/grenade shrapnel (shrapnel protection assumes you are far enough away from the blast that the blast itself doesn't kill you) and rifle rounds (and it is assumed that the rifle rounds are being fired from a few hundred meters away and not point blank), not intended to be hidden under the uniform, but worn over top of your fatigues.

    Military body armor is thicker and has external pockets for inserting trauma plates. There are two kinds of trauma plates that I'm aware of, the titanium metal plates and the ballistic ceramic plates. The ceramic plates usually (Note that I said Usually and not Always) stop a projectile dead in its tracks, but shatter on impact (thus dissipating the projectile's energy) The titanium plates can (Note that I said CAN, not always) stop a bullet dead in its tracks, spreading the impact energy over the entire area of the plate, instead of focusing the energy on a single point and allowing it to penetrate you. An impact tends to dent and/or deform the plate, weakening it with each successive shot. The ceramic plates are basically worthless after shattering and after a few dents/deformations weakening the titanium plates, they are becomes less and less able to prevent projectile penetration.

    FOOTNOTE: Just because military ballistic body armor stops a round from punching a hole through you DOES NOT make it bounce off of you. The full impact energy of the projectile is still transferred directly into you (Feels somewhat like getting hit with a baseball bat...leaves bruises and maybe breaks a rib, but it doesn't blow a hole clean through you and pierce your internal organs). The idea behind body armor is that it saves your life and the medics can fix you up...instead of tagging and bagging you for a flag draped casket ride home.

    The ceramic plate armor is good for taking one...sometimes two hits.

    The titanium armor can take a few hits, but each one makes it weaker until eventually it gives out.

    Trauma plates should be replaced after each combat encounter (Where you take a hit).

    Two full 30 round magazines of 7.62mm Ammo, fired at point blank range (such as inside a bar) would chew up body armor and finish you off. That many rounds fired full auto or even semi auto are unlikely to ALL hit an armored vest.

    There will be misses that hit the wall and a vest DOES NOT cover your arms, head, legs or feet. Any hits on unarmored body parts will punch holes through you, breaking bones, ripping muscle and cutting arteries as they pass through and exit out of your body (Forget the movie crap where some actor just grabs his arm and sez "Its a flesh wound", slaps a bandage on it and uses his arm like its just fine. That doesn't happen in the real world unless its just a graze...and even they can take a chunk of meat with them).

    If you are trying to make it realistic, a concealable vest isn't going to take 60 rounds of 7.62mm ammo and leave your man alive. Perhaps if the rifles were sub machine guns? Sub machine guns fire pistol cartridges instead of the more powerful rifle cartridges (such as an Uzi firing 9mm ammo, for example). A character spraying your MC would punch a lot of holes in the bar furniture and a stick a few slugs in your heroes vest as it rakes across him perhaps?

    If you are writing science fiction, you could have it be a new generation of technology in ballistic protection that does allow such a thing to happen, since it isn't real.
     
    1 person likes this.
  14. Killer300
    Offline

    Killer300 Active Member

    Joined:
    May 1, 2011
    Messages:
    1,064
    Likes Received:
    37
    Hmm, yeah, this does make sense. Well, this does take place in the future, but along with the improved vests there are improved bullets so not much has changed in many ways. There are vests that can stop them, and for that many rounds, but they can't be concealed. Also, I realize since this happens somewhat frequently here, the bar is going to be armored to say the least. Like, full on plating, which is actually worse for the people inside because of richochet, but bar owners don't really care about that. Yeah, you can't exactly sue people on this planet. Most disagreements are settled with violence, and bar owners are known to have rather powerful weapons and protectors, so not the best idea to mess with them usually.

    But anyway, okay, here are some questions I have.
    1. Would all the gun barrels be smoking after such intensive fire, like warship guns do after long engagements?
    2. Would the room smell heavily of gunpowder after the shootout, or does gunpowder not have a strong enough smell for that?
     
  15. -oz
    Offline

    -oz Active Member

    Joined:
    Jan 20, 2011
    Messages:
    132
    Likes Received:
    18
    Location:
    The Great Sandy Waste
    No. Under the right conditions, you can see smoke from a gunbarrel, but that's usually after multiple magazines in a fully-automatic rifle. The barrel would also be far too hot to touch. In such a situation, it looks more like heat rising off a road than it does smoke.

    Yes, there is a fairly acrid smell that will be smelled after the battle. I honestly don't know how long it would stick around in a closed environment, all my shooting experience has been outdoors.

    For the sake of accuracy, this is incorrect. Cover is something that can physically stop a bullet. Concealment is something that hides you from your assailant but might not necessarily stop a bullet. Hiding behind a spilled table would be concealment. Hiding behind a solid concrete wall would be cover.

    Another thing to address is ricochets. Your handgun bullets are more likely to ricochet than your assault rifle bullets, especially on hard surfaces like cover. Unless it hits a metal plate and simply bounces straight back, ricochets will only happen when it hits within around 15 degrees of the surface plane (as in almost parallel). While a ricochet can and does kill, the next bullet from the gun has a much better chance at killing someone than does the ricochet, especially if they're wearing body armor.
     
    1 person likes this.
  16. Porcupine
    Offline

    Porcupine Contributing Member

    Joined:
    Feb 13, 2011
    Messages:
    346
    Likes Received:
    21
    Location:
    Frankfurt, Germany
    -oz is right. Great post by Lothgar (as usual) too.

    Ah, yes, I see. The same word "Deckung" is used for both in German, which is why I brought the two together.
     
  17. Laser Sailor
    Offline

    Laser Sailor Member

    Joined:
    Jul 29, 2010
    Messages:
    36
    Likes Received:
    0
    I don't care what kind of armor someone has, 60 rounds of 7.62 will kill them. The blunt impact force alone would be enough. And given that even level IV ceramic plates only protect against 1-2 rounds under the best circumstances, no kind of concealable body armor can take that kind of hit. Concealable body armor is usually in the level 2a to 3a range, which will stop most handgun rounds (9mm, .45 ACP, .44 Magnum) but even though the bullet does not penetrate the body, there will still be pretty serious damage from even one shot.

    If your bar is typical, made of hardwood oak furnature, then ricochets are unlikely. And even the 9mm rounds will go through tables and the bar itself. A big heavy assault rifle round such as a 7.62x39 (Ak-47) will drive right through as well. But ironically a small and light assault rifle round such a the 5.56x45 (M16, M4 etc) will break apart after going through something as light as drywall, rendering it relatively harmless to someone on the other side (unless it's a steel core round).
     

Share This Page