WEBVTT - TechStuff Classic: TechStuff Looks at Ballistics 0:00:04.120 --> 0:00:07.160 Get in touch with technology with tech Stuff from how 0:00:07.200 --> 0:00:14.200 stuff works dot com. Hey there, and welcome to tech Stuff. 0:00:14.240 --> 0:00:18.040 I'm Jonathan Strickland. I'm the host of this podcast. I'm 0:00:18.040 --> 0:00:20.479 executive producer at how Stuff Works, and I heart radio 0:00:20.480 --> 0:00:22.960 and I love all things tech. Into this time for 0:00:23.000 --> 0:00:28.600 another classic episode of tech Stuff. This episode originally published 0:00:28.640 --> 0:00:32.479 on April eight, two thousand and twelve, and Chris Pallette, 0:00:32.800 --> 0:00:35.760 my former editor and co host, and I decided to 0:00:35.760 --> 0:00:40.320 sit down and talk about the science of ballistics and 0:00:40.720 --> 0:00:45.800 using a ballistic forensic science too to investigate a crime scene. 0:00:46.240 --> 0:00:48.760 So you are about to hear this classic episode where 0:00:48.800 --> 0:00:52.680 Chris and I kind of dig down into this very 0:00:52.720 --> 0:00:58.120 interesting field. I hope you enjoy. We did a podcast 0:00:58.160 --> 0:01:01.360 on nuclear weapons recently, Yes, we did, um, and right 0:01:01.400 --> 0:01:03.840 in the middle of it, for reasons that I can't 0:01:03.920 --> 0:01:06.840 even fathom, I started thinking about other kinds of weapons 0:01:06.840 --> 0:01:08.880 and I thought, you know what, it would be kind 0:01:08.920 --> 0:01:13.520 of interesting to do a podcast on ballistics, which is 0:01:13.560 --> 0:01:20.320 basically the science of figuring out moving stuff projectiles work. Yeah, yeah, 0:01:20.440 --> 0:01:24.880 I I was. I agree, that was a cool idea. Yeah, 0:01:24.880 --> 0:01:28.319 it's the science of deals with motion of projectiles. But 0:01:28.400 --> 0:01:30.800 of course it's been used. Sorry, I didn't mean it 0:01:30.840 --> 0:01:33.319 interrupt I was gonna say that, you know, ballistics, It 0:01:33.400 --> 0:01:38.559 also is kind of shorthand for a specific branch of forensics. Yes, 0:01:38.840 --> 0:01:41.880 which is really what we're focusing on today. Yes, because 0:01:43.040 --> 0:01:45.040 when you get down to it, the actual study of 0:01:45.040 --> 0:01:49.360 ballistics is in large part a matter of physics. Yes. Yes, 0:01:49.400 --> 0:01:52.240 there's a lot of science involved in this. We know 0:01:52.280 --> 0:01:57.320 how we much we hate science, dad gum it um. 0:01:57.400 --> 0:02:03.640 Unfortunately for the scientists, but fortunately for h crime mystery writers. 0:02:04.560 --> 0:02:09.760 Bullets do not always behave themselves in terms of physics. Like, 0:02:10.120 --> 0:02:12.760 they generally go where they're supposed to go, but they 0:02:12.760 --> 0:02:16.600 don't always follow the normal path when they get there. Yeah, 0:02:16.720 --> 0:02:20.600 let's just say that it's all due to little, tiny 0:02:20.800 --> 0:02:25.080 individual differences on a very small scale. Because we don't 0:02:25.080 --> 0:02:28.400 mean to say that bullets somehow defy the laws of physics. No, 0:02:28.760 --> 0:02:31.800 but they don't always. They do always travel a predictable path, 0:02:31.960 --> 0:02:34.840 right right. You might think, oh, well, if so and 0:02:34.880 --> 0:02:38.520 so was standing here and shot such and such over there, 0:02:38.600 --> 0:02:41.680 then the bullets should be right here. That's that's not 0:02:41.760 --> 0:02:47.040 always the case. Even even saying the cartridge for the 0:02:46.080 --> 0:02:49.160 the case for the cartridge should be right here. That's 0:02:49.200 --> 0:02:51.880 not always the case either. So to really understand this, 0:02:51.919 --> 0:02:53.280 first of all, we need to talk a little bit 0:02:53.280 --> 0:02:58.440 about how the forensics part of ballistics all came about 0:02:58.480 --> 0:03:02.400 in the first place. Yes, and and really ballistics people 0:03:02.400 --> 0:03:08.360 have been trying to get the science behind uh forensics 0:03:08.400 --> 0:03:12.280 ballistics down for quite some time, but it hasn't really 0:03:12.320 --> 0:03:15.400 been that long that we really got it down pat. 0:03:15.480 --> 0:03:19.160 I mean, in the nineteenth century, Uh, there were people 0:03:19.160 --> 0:03:20.840 who were trying to figure out how to do this, 0:03:20.919 --> 0:03:22.880 but they were the methods they were using were not 0:03:23.000 --> 0:03:26.680 at all scientific, right, And to understand how you would 0:03:26.720 --> 0:03:31.560 be able to use ballistics to try and identify a 0:03:31.600 --> 0:03:34.480 weapon that fired a particular projectile, you have to understand 0:03:34.520 --> 0:03:37.920 a little bit more about what goes on with these projectiles. 0:03:38.480 --> 0:03:48.200 So sometime around oh, the late fifteen century, uh, the 0:03:48.400 --> 0:03:51.520 people who were creating firearms at that time discovered something 0:03:52.040 --> 0:03:55.920 which was that if you were to have a barrel 0:03:56.200 --> 0:04:00.480 of a weapon have some grooves in it to help 0:04:01.280 --> 0:04:04.960 direct the projectile to spin as it comes out of 0:04:04.960 --> 0:04:10.200 the barrel, you improve the stability of that projectile's flight. Yeah. 0:04:10.200 --> 0:04:13.600 Previously they were what you call smooth bore which was 0:04:13.640 --> 0:04:17.000 basically a a smooth tube. The inside of it was smooth, 0:04:17.120 --> 0:04:19.760 so you would, uh, you know, say take your musket 0:04:20.200 --> 0:04:24.560 and fire a shot, fire a shot from it. Um. Actually, 0:04:24.760 --> 0:04:26.880 you know this is this is I was getting ready 0:04:26.920 --> 0:04:28.520 to dismiss this in my head, but I think we 0:04:28.560 --> 0:04:31.159 should mention this. Um. You know those early muskets where 0:04:31.200 --> 0:04:34.600 you would you know, uh, you'd have to get everything ready. 0:04:34.600 --> 0:04:36.279 You'd have to put the wadding and the and the 0:04:36.320 --> 0:04:38.640 powder in and then the musket ball and tamp it 0:04:38.680 --> 0:04:40.920 all down with the rod before you could fire the weapon. 0:04:41.360 --> 0:04:43.839 You know, whether it's matchlock or flint lock, which we 0:04:43.880 --> 0:04:47.640 talked about in another podcast. Um, but you have a 0:04:48.120 --> 0:04:52.479 basically a roundsh ball made of lead which is fired 0:04:53.200 --> 0:04:57.680 using um, the explosive gunpowder and the the gases propelled 0:04:57.680 --> 0:05:00.279 the ball out of the tube, and you know they go, well, 0:05:00.480 --> 0:05:02.800 they go where they go. They generally go in the 0:05:02.839 --> 0:05:06.720 direction that the barrel was pointing. Yes, more specific than 0:05:06.760 --> 0:05:10.440 that we cannot naked. Yeah, they weren't nearly as accurate 0:05:10.480 --> 0:05:12.800 as a rifled barrel, which is what which is what 0:05:12.880 --> 0:05:15.760 Jonathan was just talking about, where they there are grooves 0:05:15.920 --> 0:05:21.080 inside the barrel and they are um, and they travel 0:05:21.080 --> 0:05:23.760 in a spiral patterns. I remember, correctly, didn't we talk 0:05:23.800 --> 0:05:27.880 about something in the rim when they started grooving the barrel? 0:05:27.920 --> 0:05:30.640 But they weren't. They weren't in a spiral pattern. They 0:05:30.680 --> 0:05:33.960 were straight. It might may have been I remember, I'm sorry, 0:05:34.200 --> 0:05:37.280 I just came to mind. But eventually they did hit 0:05:37.320 --> 0:05:41.159 onto the fact that a helical groove spiral groove would 0:05:41.320 --> 0:05:45.520 h helical'd on where where that would create enough spend 0:05:45.560 --> 0:05:47.880 so that the projectile would become much more stable off 0:05:47.920 --> 0:05:51.480 Like this is the same sort of idea you get 0:05:51.520 --> 0:05:54.240 when you have a football player throwing a football, absolutely 0:05:54.320 --> 0:05:58.400 American football. American football player, Um, how to touch the 0:05:58.400 --> 0:06:00.000 ball with your hands? You know when you hear about 0:06:00.000 --> 0:06:02.680 like when you hear about like a tight spiral that 0:06:02.800 --> 0:06:06.880 helps that projectile, in this case the American football maintain 0:06:07.080 --> 0:06:11.520 a precise flight path. Well, while that was very useful 0:06:11.720 --> 0:06:16.919 in making firearms more accurate, it was not thought of 0:06:17.080 --> 0:06:19.800 as a way of identifying a firearm based upon a 0:06:19.800 --> 0:06:22.719 projectile that had been fired for several centuries. It wasn't 0:06:22.800 --> 0:06:26.760 until the eighteen hundreds. Yeah, and uh, actually I have 0:06:27.240 --> 0:06:30.919 the earliest and this this is all from a website 0:06:30.920 --> 0:06:34.400 called Firearms i D. And it was created by a 0:06:34.400 --> 0:06:40.080 guy named Scott Doyle who did some amazing research on ballistics, 0:06:40.120 --> 0:06:42.400 the history of it and all of the elements that 0:06:42.480 --> 0:06:46.760 go into identifying firearms. If you are interested in the subject, 0:06:46.760 --> 0:06:49.440 I recommend you check out Firearms i D because it 0:06:49.560 --> 0:06:53.000 is truly exhaustive. I'm only going to give a small 0:06:53.040 --> 0:06:58.040 fraction of what he made available. So the earliest event 0:06:58.200 --> 0:07:03.040 he found, the earliest documented case of identifying a firearm 0:07:03.560 --> 0:07:07.920 UH in a criminal case happened in eight in London, 0:07:08.560 --> 0:07:14.360 and what had happened was a homeowner was killed by 0:07:14.360 --> 0:07:18.200 by a gun and a servant was suspected of being 0:07:18.400 --> 0:07:23.960 the perpetrator. And UH a fellow named Henry Goddard UM 0:07:24.360 --> 0:07:27.720 who was with the London Police or with a branch 0:07:27.800 --> 0:07:31.960 of the London Police, was assigned the case and he 0:07:32.720 --> 0:07:38.520 examined the the the projectile that killed this shop owner 0:07:39.080 --> 0:07:42.160 and determined that it was made by a particular mold 0:07:42.920 --> 0:07:46.200 um by UH, which meant that it came from a 0:07:46.240 --> 0:07:51.119 specific company. And then he looked at the paper patch 0:07:51.240 --> 0:07:55.720 that was used in the the the firing as well. Now, 0:07:55.720 --> 0:07:58.120 this paper what it did was it created a seal 0:07:58.280 --> 0:08:03.200 between the powered and the projectile so that when the 0:08:03.200 --> 0:08:06.680 powdering knights and the gases expand, the projectile would have 0:08:06.760 --> 0:08:08.640 a good seal on it, so it would it would 0:08:08.640 --> 0:08:11.680 fly out properly. And you saw that this paper patch 0:08:11.760 --> 0:08:16.160 had been made from some newspaper that had been in 0:08:16.200 --> 0:08:18.680 the room. He actually found the page where the newspaper 0:08:18.680 --> 0:08:22.000 had been torn to make that patch, and so they 0:08:22.000 --> 0:08:25.120 were able to determine that it was in fact the 0:08:25.200 --> 0:08:28.680 servant who appeared to have fired on this shop owner. 0:08:29.600 --> 0:08:32.160 And so that was the first case. Now in that case, 0:08:32.240 --> 0:08:35.720 it wasn't an idea, you know, specifically checking the bullet 0:08:35.800 --> 0:08:40.360 for the spiral marks that would indicate, um, what gone 0:08:40.360 --> 0:08:42.480 fired it, because that's that's something else we should mention. 0:08:42.600 --> 0:08:45.480 These rifling marks, uh ifact, That's why we call it 0:08:45.480 --> 0:08:48.520 a rifle. There's these rifling marks that are on the 0:08:48.520 --> 0:08:52.640 bullet itself. That's that's caused as a bullet travels down 0:08:52.720 --> 0:08:59.480 this this grooved barrel, it cards little scratches into the bullet. Yes, 0:09:00.160 --> 0:09:04.640 and so these scratches are unique to a particular weapon. 0:09:05.160 --> 0:09:07.600 Even even two weapons of the same make and model 0:09:08.240 --> 0:09:12.080 will produce different scratches, at least on a on a 0:09:12.120 --> 0:09:15.439 tiny you know, beyond a superfluous glance, you'll be able 0:09:15.480 --> 0:09:19.160 to see that there are differences, and so it's almost 0:09:19.200 --> 0:09:23.520 like a fingerprint. If you are able to see, you know, 0:09:23.600 --> 0:09:27.800 tell that two different bullets are close enough and identity 0:09:27.880 --> 0:09:31.000 that these these markings are really really, you know, to 0:09:31.120 --> 0:09:34.560 all intents and purposes identical. You can say that they 0:09:34.559 --> 0:09:36.680 were both fired by the same weapon. So if you 0:09:36.720 --> 0:09:39.280 happen to have that weapon in your possession and you've 0:09:39.320 --> 0:09:41.679 done a bunch of test firings and all the bullets 0:09:41.679 --> 0:09:43.480 are coming out the same way and they matched the 0:09:43.520 --> 0:09:45.920 bullet that was used in a crime, you can feel 0:09:45.920 --> 0:09:48.560 pretty confident saying that that, in fact was the weapon 0:09:48.600 --> 0:09:53.000 that was used in that crime. Um. So yeah, I 0:09:53.000 --> 0:09:56.880 mean there, Um, there are many cases in which you 0:09:56.920 --> 0:09:59.280 know this has been this has been used. I mean 0:10:00.000 --> 0:10:01.480 one of the first I read, and I read an 0:10:01.480 --> 0:10:07.040 excellent article by Katherine ramsland um in uh in which 0:10:07.080 --> 0:10:10.240 she was talking about do you remember learning about Sacco 0:10:10.360 --> 0:10:14.360 and Vanzetti in your American history class? This very controversial? 0:10:14.440 --> 0:10:19.520 Absolutely absolutely, Um. This was a case in which, uh, Um, 0:10:19.679 --> 0:10:23.440 the payroll was being delivered to a shoe factory and 0:10:23.679 --> 0:10:27.839 a a couple of guys came up and shot the 0:10:28.440 --> 0:10:31.360 guards and UM, you know, they basically made off with 0:10:31.360 --> 0:10:35.320 the money and UH so they started looking for information. 0:10:35.320 --> 0:10:40.199 This by the way, was April fifty, UM, and this 0:10:40.280 --> 0:10:44.440 is when they started looking. Uh. This really was the 0:10:44.480 --> 0:10:49.520 incident that made modern ballistics a science, I think, UM, 0:10:49.559 --> 0:10:52.800 just from from the way they handled it. So UM, 0:10:52.920 --> 0:10:57.560 the investigators behind this uh collected all the evidence they could, 0:10:57.559 --> 0:11:00.680 including the the spent shell casings. UM. They went back 0:11:00.720 --> 0:11:04.679 to looking at the manufacturers of of weapons. UM. There 0:11:04.679 --> 0:11:07.600 were about six at the time that they looked at, 0:11:07.640 --> 0:11:10.080 and uh they turned out to be Remington, Winchester, and 0:11:10.120 --> 0:11:14.480 Peters UM that that could use these these casings. UM. 0:11:14.720 --> 0:11:19.600 And what they what they ended up doing was they started, 0:11:19.920 --> 0:11:23.840 uh you know, looking around at you know, what they 0:11:23.880 --> 0:11:27.600 could get from this information. And as it turns out, 0:11:27.640 --> 0:11:30.320 one of the incriminating factors was the fact that for 0:11:30.480 --> 0:11:33.240 one of the weapons that they had, the only bullets 0:11:33.280 --> 0:11:36.840 that they could find, uh that would fit that weapon 0:11:37.720 --> 0:11:43.440 or in Psacho's pocket. UM, which is pretty incriminating evidence, 0:11:43.440 --> 0:11:47.400 but it's not exactly that's circumstantial, you know. UM. So 0:11:47.480 --> 0:11:49.080 what they did was they talked to somebody who had 0:11:49.120 --> 0:11:52.400 worked with uh sort of preliminary ballistics technology. His name 0:11:52.480 --> 0:11:56.360 was Albert H. Hamilton's and UH he actually had been 0:11:57.040 --> 0:12:02.760 UM working with UH with other cases and UH he 0:12:03.280 --> 0:12:08.200 wasn't completely scientific um in his methods, but he he 0:12:08.320 --> 0:12:11.120 actually got stuck in the middle of the case and 0:12:11.200 --> 0:12:15.320 during this UH the Sacco and Vanzettie case, UM came 0:12:15.360 --> 0:12:19.760 in with new weapons that were uh similar to the 0:12:19.760 --> 0:12:22.480 ones that they had and and basically disassembled them in 0:12:22.520 --> 0:12:25.600 front of the judge who noticed that he was swapping 0:12:25.679 --> 0:12:28.760 parts with the other gun and went, no, you can't 0:12:28.800 --> 0:12:31.439 do that, and they threw it out. But they did 0:12:31.480 --> 0:12:35.920 give the information to Calvin Goddard, someone who is quite 0:12:35.960 --> 0:12:40.120 famous in ballistics forensics. Yeah, he's he's I would argue 0:12:40.120 --> 0:12:42.480 that he's probably considered by many people to be the 0:12:42.520 --> 0:12:46.600 father of this technology. He worked with a guy named 0:12:46.679 --> 0:12:49.600 Charles Waite at in New York with the Bureau of 0:12:49.640 --> 0:12:54.280 Forensic Ballistics, and he was using microscopes and a helixometer, 0:12:54.600 --> 0:12:57.200 which is a probe that you could use to look 0:12:57.240 --> 0:12:59.959 at gun barrels. UM. I imagined that was used in 0:13:00.000 --> 0:13:03.760 the manufacturing of these weapons. UM. But what he did 0:13:03.840 --> 0:13:07.800 was he fired these the weapons used or or in 0:13:07.840 --> 0:13:12.040 Sacco and Vanzetti's possession um into a lot of cotton 0:13:12.679 --> 0:13:16.520 and compared the casing and the bullet to the ones 0:13:17.120 --> 0:13:24.360 recovered in the investigation, and they were similar enough, um 0:13:24.400 --> 0:13:29.240 to incriminate both of them. Now, um, Vanzetti, I mean, 0:13:29.280 --> 0:13:31.920 they put both of them to death. But Vanzetti said 0:13:31.920 --> 0:13:36.720 he was innocent, and uh apparently Sacco's uh last words 0:13:36.720 --> 0:13:40.480 were long live anarchy, which doesn't exactly uh he he 0:13:40.520 --> 0:13:43.400 doesn't exactly say, well, you know, I didn't do any 0:13:43.440 --> 0:13:47.880 of that. But yeah, and in later years too, they've 0:13:47.880 --> 0:13:51.760 still they continue to examine that and uh, right now, 0:13:51.800 --> 0:13:55.240 although it's still controversial whether or not these guys were 0:13:56.080 --> 0:14:00.960 railroaded or whether or not they actually did commit the crime. Um, Uh, 0:14:01.000 --> 0:14:06.160 they still say that, Uh, the weapons still support Goddard's 0:14:06.160 --> 0:14:09.720 findings even years later. So the technology we're using now 0:14:11.040 --> 0:14:13.560 suggest that those weapons were the ones used. Yeah. The 0:14:14.600 --> 0:14:18.240 that Bureau of Forensic Ballistics was formed in in April 0:14:18.320 --> 0:14:21.560 nineteen five in New York City, and the whole purpose 0:14:21.640 --> 0:14:25.160 behind it was that by you remember, back in eighteen 0:14:25.200 --> 0:14:27.560 thirty five was the first time we see someone trying 0:14:27.600 --> 0:14:31.720 to identify a firearm, uh, after a crime has happened 0:14:32.200 --> 0:14:36.640 the firearm itself was the one that was used by NIVE. 0:14:37.360 --> 0:14:40.840 There had been a lot of pioneers who worked on 0:14:41.480 --> 0:14:45.280 this idea of identifying firearms based upon the projectiles they fired. 0:14:46.320 --> 0:14:52.360 And uh, the problem was that the the resources were scattered, right. 0:14:52.400 --> 0:14:54.800 I mean, you had you had some communities that might 0:14:54.840 --> 0:14:57.840 have an expert that resides within that community, but then 0:14:58.080 --> 0:15:00.200 you know, you might have hundreds of miles of of 0:15:00.320 --> 0:15:03.720 area where there is no expert, there's no one to 0:15:03.760 --> 0:15:07.000 call upon. And so the Bureau was formed as a 0:15:07.080 --> 0:15:10.960 resource for law enforcement agencies across the United States. There 0:15:10.960 --> 0:15:13.840 were other countries that were doing similar things. Actually, a 0:15:13.840 --> 0:15:17.480 lot of this early research where the idea was, hey, look, 0:15:17.480 --> 0:15:20.160 they are these markings on this bullet. They're consistent with 0:15:20.240 --> 0:15:22.600 every bullet that's fired from this particular gun, and they're 0:15:22.600 --> 0:15:25.040 different from all the ones that are fired from that gun. 0:15:25.720 --> 0:15:27.480 That kind of work was being done all over the world. 0:15:27.480 --> 0:15:29.120 In fact, there were a lot of people in France 0:15:29.400 --> 0:15:33.520 who wrote a lot of instrumental early papers on identifying 0:15:33.520 --> 0:15:37.880 firearms based upon their projectiles or Yeah, and then to 0:15:38.080 --> 0:15:40.880 the FBI. The Federal Bureau of Investigation here in the 0:15:40.960 --> 0:15:45.240 United States was directed by a their jaunty head of 0:15:45.320 --> 0:15:49.480 staff Jagger Hoover. Yes, I think that's the first time 0:15:49.520 --> 0:15:51.760 I've ever heard is I think that's what Jay stands for, right, 0:15:51.880 --> 0:15:57.720 John T. Edgar Hoover, Um, No, not at all. Uh 0:15:57.720 --> 0:16:00.320 he know. I was more like really said that elite. 0:16:00.880 --> 0:16:04.040 Uh So it was a question mark, like the sarcastic kind. 0:16:04.280 --> 0:16:08.880 It wasn't actually an interrobang, gotcha. So he directed that 0:16:09.080 --> 0:16:13.000 the FBI should create a lab for ballistics forensics as well, 0:16:13.280 --> 0:16:16.480 and so this was becoming really serious business, and there 0:16:16.520 --> 0:16:19.720 were there were a lot of early cases between you know, 0:16:19.760 --> 0:16:23.640 the late eighteen hundreds and and nineteen twenty that established 0:16:24.000 --> 0:16:27.720 that this was a legitimate means of investigation. So let's 0:16:27.720 --> 0:16:30.320 talk a little bit more about what you actually do 0:16:30.480 --> 0:16:33.520 when you're trying to identify whether or not a particular 0:16:33.560 --> 0:16:35.680 bullet was fired from a particular gun. First of all, 0:16:36.680 --> 0:16:40.320 it helps if we if we talk about bullets and cartridges, 0:16:40.360 --> 0:16:42.800 because we and we've done this in another podcast, but 0:16:43.200 --> 0:16:45.040 it always helps because a lot of I think people 0:16:45.040 --> 0:16:49.040 who are generally unfamiliar with guns don't know the anatomy 0:16:49.080 --> 0:16:51.080 of a gun. Yep. And that's part of why I 0:16:51.120 --> 0:16:55.640 wanted to mention that about the muskets um because you know, 0:16:55.880 --> 0:16:58.480 after a while they realized that the system that we're 0:16:58.480 --> 0:17:01.400 about to talk about, it makes the weapons much more 0:17:01.440 --> 0:17:05.520 reliable using those things, and faster to operate because rather 0:17:05.560 --> 0:17:07.159 than having to put the powder in the in the 0:17:07.560 --> 0:17:10.360 wadding and all that stuff in there and and prepare 0:17:10.480 --> 0:17:13.480 the weapon to be fired. I mean, I saw I 0:17:13.480 --> 0:17:14.960 can't even remember what show it was. I saw a 0:17:15.000 --> 0:17:17.400 thing on TV where they had somebody firing and must 0:17:17.440 --> 0:17:19.520 get as fast as they could, just to see how 0:17:19.600 --> 0:17:24.320 quickly a trained um musketeer could fire a weapon. It's 0:17:24.359 --> 0:17:27.000 about three times per minute. Three times per minute is 0:17:27.040 --> 0:17:30.600 considered an excellent time fast. Yeah, I know, I've seen 0:17:31.080 --> 0:17:36.000 I've seen artillery cruise that we're using, uh period cannon's 0:17:36.560 --> 0:17:39.119 um actually wasn't a cannon, but anyway, it was. It 0:17:39.160 --> 0:17:42.440 was an artillery gun, period artillery gun. And they talked 0:17:42.480 --> 0:17:46.560 about how even with a well trained group of troops 0:17:46.680 --> 0:17:49.600 who were familiar with the weapon, three times a minute 0:17:49.680 --> 0:17:54.439 was considered to be the peak performance. So one of 0:17:54.480 --> 0:17:57.680 the biggest innovations was the idea of why don't we 0:17:57.720 --> 0:18:01.040 take the system of gunpowder and wadding and shot and 0:18:01.080 --> 0:18:03.080 all that, and why don't we try and figure out 0:18:03.080 --> 0:18:06.199 a way of packaging it all into one thing that 0:18:06.320 --> 0:18:09.560 you load into a gun once and then you fire. 0:18:10.000 --> 0:18:11.919 So instead of having to load in all these separate 0:18:11.920 --> 0:18:15.280 pieces and pack them together and hope that it fires correctly, 0:18:15.600 --> 0:18:18.320 it's all packaged together. And that's the idea behind the cartridge. 0:18:19.200 --> 0:18:22.439 In fact, the earliest cartridges were these little paper cartridges 0:18:22.920 --> 0:18:26.360 that had everything packed together, and uh, they were used 0:18:26.359 --> 0:18:29.080 in the Civil War mainly, but then actually that was 0:18:29.119 --> 0:18:30.920 sort of the step between where you put the cartridge 0:18:30.960 --> 0:18:33.840 in and then and then the musket ball right right, 0:18:33.840 --> 0:18:36.879 the shot. Yeah, the cartridge contained essentially all the stuff 0:18:36.920 --> 0:18:41.240 that you would have put in previously besides the shot itself. Well, 0:18:41.560 --> 0:18:47.040 the modern day cartridges have the the fuel that's going 0:18:47.080 --> 0:18:50.280 to push the the bullet forward, and the bullet itself 0:18:50.280 --> 0:18:53.600 all packed together. So you've got a case that's typically 0:18:53.640 --> 0:18:56.479 made out of something like brass or maybe steel, depends 0:18:56.520 --> 0:19:01.040 on the particular manufacturer, and the ammunition involved a typically brass, 0:19:01.320 --> 0:19:03.560 and then you have a bullet at the end. The 0:19:03.600 --> 0:19:06.600 bullet is the actual projectile that will fire out the gun. 0:19:06.840 --> 0:19:11.080 The case remains behind. Now, the case also contains it 0:19:11.119 --> 0:19:15.640 contains powder, primer and a primer mix and uh, and 0:19:15.680 --> 0:19:18.639 that's the stuff that when a firing pin from the 0:19:18.640 --> 0:19:21.760 weapon hits the primer, that ignites the primer, which then 0:19:21.760 --> 0:19:26.320 in turn ignites the powder which creates this massive amount 0:19:26.320 --> 0:19:29.080 of gas. Massive and a relative term, I should say, 0:19:29.600 --> 0:19:33.360 um amount of gas within the case. That's what pushes 0:19:33.400 --> 0:19:38.120 that that bullet out of the weapon. So the case 0:19:38.160 --> 0:19:42.240 remains behind. The case is actually altered by this because 0:19:42.280 --> 0:19:46.080 the gases are pretty hot. Then they pushed pretty hard, 0:19:46.480 --> 0:19:48.639 so the case itself will change a little bit. Then 0:19:48.680 --> 0:19:51.320 you have to extract the case from the weapon and 0:19:51.359 --> 0:19:54.119 put a new cartridge in its place in the chamber 0:19:54.160 --> 0:19:56.440 of the weapon in order to fire it again. And 0:19:56.520 --> 0:20:00.119 of course we've also talked about machine guns. Uh, if 0:20:00.119 --> 0:20:02.280 you're talking about an automatic weapon, you put in you 0:20:02.640 --> 0:20:09.159 have a magazine feeding mechanism, feeding mechanism that will automatically 0:20:09.560 --> 0:20:12.240 pop the next it will pop the spent cartridge out 0:20:12.440 --> 0:20:15.560 of the weapon, and uh, load the next cartridge in 0:20:15.600 --> 0:20:18.760 and ready to be fired. And it happens very very quickly. 0:20:19.000 --> 0:20:22.320 So but it operates on the same same principle. So 0:20:22.440 --> 0:20:24.920 here's the interesting thing, A couple of interesting things. First 0:20:24.920 --> 0:20:27.680 of all, we talked about the rifling with the grooves 0:20:27.720 --> 0:20:30.919 within the barrel which are going to cut into the bullet, 0:20:31.840 --> 0:20:34.639 making a fingerprint on that bullet, so that if you 0:20:34.680 --> 0:20:37.600 were to find two bullets fired by the same gun 0:20:37.720 --> 0:20:39.520 and you were to compare them side by side, you 0:20:39.520 --> 0:20:43.199 should be able to see the same markings on both 0:20:43.640 --> 0:20:46.960 because it's it's going to carve it out the same way. Well, 0:20:47.119 --> 0:20:51.720 the same sort of thing goes plays for the cartridge 0:20:51.840 --> 0:20:54.720 or like the case, rather for the cartridge. Um, the case, 0:20:54.920 --> 0:20:57.199 the spent cartridge is going to have some markings on 0:20:57.240 --> 0:21:00.280 it as well. Um, some of it may be matches 0:21:00.440 --> 0:21:02.960 just from you know, the way that it sits in 0:21:03.040 --> 0:21:06.639 the chamber, or if there if there's an extractor, if 0:21:06.640 --> 0:21:10.000 there's an actual mechanical element in there that kicks that 0:21:10.119 --> 0:21:14.919 spent cartridge out, that can leave a mark on the 0:21:15.000 --> 0:21:17.760 case as well. So that way, if you don't maybe 0:21:17.800 --> 0:21:19.320 you don't even have the bullets, maybe you just have 0:21:19.400 --> 0:21:23.360 to spent cases, you can compare those and see. So 0:21:23.400 --> 0:21:27.040 I stepped one of identifying the weapon is identifying what 0:21:27.440 --> 0:21:30.720 caliber of bullet was used, and you know what kind 0:21:30.720 --> 0:21:33.760 of cartridge was used, because that will limit the type 0:21:33.840 --> 0:21:37.800 of weapons that could have fired that particular ammo, right, 0:21:37.840 --> 0:21:41.119 because not every gun fires every immunition. Because anyone who 0:21:41.160 --> 0:21:44.440 has ever worked with guns nose are very specific kinds 0:21:44.440 --> 0:21:47.240 of ammo that work with particular guns, and you cannot 0:21:47.440 --> 0:21:50.159 you cannot interchange them. Chris and I have more to 0:21:50.200 --> 0:21:54.200 say about ballistics and forensics science, but first let's take 0:21:54.320 --> 0:22:04.679 a quick break to thank our sponsor. Each weapon. Now, 0:22:04.720 --> 0:22:07.159 each manufacturer when they make when they put the grooves 0:22:07.160 --> 0:22:12.159 in there and the the section between UM. Basically the 0:22:12.280 --> 0:22:15.639 ridges around the grooves are called lands. UM. Those metal 0:22:15.720 --> 0:22:22.280 ridges basically are what helped the bullet reach its destination 0:22:22.359 --> 0:22:26.840 by providing it the spin and accuracy UM. But they 0:22:26.880 --> 0:22:32.200 also are are common to manufacturers. So one weapons manufacturer 0:22:32.280 --> 0:22:37.439 might put six grooves in the barrel, one might use four. UM. 0:22:37.560 --> 0:22:40.080 So one of the things these marks left and they 0:22:40.119 --> 0:22:42.800 are unique to every weapon. UM. These marks are going 0:22:42.840 --> 0:22:46.879 to help the forensics investigator if if if they can 0:22:46.920 --> 0:22:49.280 find the bullets, they're going to be able to identify 0:22:50.160 --> 0:22:53.359 which manufacturer made the gun. That will help track it 0:22:53.400 --> 0:22:55.720 down and then from there they can look at other 0:22:55.760 --> 0:22:58.760 things that will help them at least narrow down and say, well, 0:22:58.760 --> 0:23:01.399 this couldn't have been Uh, this couldn't have been the 0:23:01.440 --> 0:23:03.520 gun that fired it because it's not even the same manufacturer. 0:23:03.560 --> 0:23:05.399 It's not the right people. So we can rule this 0:23:05.480 --> 0:23:08.320 out because there they can look at specific guns, because 0:23:08.400 --> 0:23:11.600 multiple manufacturers can make the same type of gun. Yes, 0:23:11.680 --> 0:23:15.040 so yeah, so narrowing it down to your first you 0:23:15.040 --> 0:23:17.560 look at the caliber of the bullet, uh, and the 0:23:18.560 --> 0:23:20.840 case so that you can determine what kind of ammo 0:23:20.960 --> 0:23:23.560 was used. That narrows it down to a range of 0:23:23.600 --> 0:23:27.000 weapons that might be able to fire that. Looking at 0:23:27.000 --> 0:23:30.640 the actual patterns on the bullet itself and well, we'll 0:23:30.680 --> 0:23:34.560 give you at least an idea of of the specific 0:23:34.760 --> 0:23:38.760 type of weapon used and the manufacturer. And then again 0:23:38.840 --> 0:23:42.240 comparing that bullet with one like a test bullet fired 0:23:42.320 --> 0:23:45.919 from a weapon. We'll let you know if it's fired 0:23:45.960 --> 0:23:49.200 from the same weapon. So you're you keep narrowing it down. 0:23:49.240 --> 0:23:51.240 This is very scientific. I mean you're talking about going 0:23:51.240 --> 0:23:54.320 from the general to the very specific. So you're just 0:23:54.720 --> 0:23:58.000 eliminating all the other options until what you're left with 0:23:58.160 --> 0:24:04.480 is the only, hopefully the only uh possible answer. And um, 0:24:04.520 --> 0:24:06.760 there are a lot of different ways that that these 0:24:07.560 --> 0:24:12.359 the cartridges can have marks on Besides the ejection UM mark, 0:24:12.480 --> 0:24:16.080 there can be firing pen marks, so you can see 0:24:16.119 --> 0:24:19.760 how the firing pin struck the bottom of the cartridge. 0:24:20.240 --> 0:24:22.359 That will tell you a lot about the type of weapon. 0:24:22.440 --> 0:24:25.720 Like there's certain weapons that have a very distinct firing 0:24:25.760 --> 0:24:29.199 pen mark, so like a square, one's good indicator that 0:24:29.359 --> 0:24:32.879