ballistics opinion

[Alpo]

Do you believe that a forensic lab could tell the difference with bullets that are only two or three 1,000 of an inch difference?

 

On television they can always tell you whether that was a 9 mm or that was a 38 special, but the nine uses the 0.355 and the 38 uses a .357 and there ain't a whole lot of difference there. But they can always tell you on TV. Reckon they could in real life?

 

The murder weapon in the movie I am currently watching is a 32. But is it a 32 automatic, which normally has a fmj77 grain bullet, or a 32 long, which normally has a lead round nose 88 grain bullet, or a 32 Winchester which normally has a lead round nose flat 100 grain bullet. And I can tell the difference by weighing the bullet. If it was all there. But the 32 automatic uses a smaller in diameter bullet than a 32 revolver. Can they tell by that?

 

I remember a cop show where the murder weapon was 30 caliber. It turned out to be an automag 2 in 30 M1 carbine. And I was just amazed that they could tell the difference between that 308 bullet and a 311 .32.

 

I bet you I could load a 32 Smith & Wesson long into my Ruger Blackhawk 30 carbine cylinder - where it will fit and it will fire because I have tried it and I know it will fit and it will fire - and shoot that 311 bullet down that 308 barrel and confuse the ballistics tech all to hell.

[Abilene Slim SASS 81783]

I’d love to see how TV forensics would ID a hollow point plucked from the victim. Hollywood bullets are always so pristine.
 

I haven’t watched a TV cop show all the way through since the 70’s. Has that situation ever come up on these shows?

[Sgt. C.J. Sabre, SASS #46770]

As a for instance, 9mm bullets are different than .38s by type. A 9mm typically uses a 115, 124 or 148 grain bullet, while a .38 might use a 110, 125, or 158 grain bullet. 9mm will usually be a FMJ, while a .38 will usually use a lead or semi jacketed bullet. These aren't absolutes of course, but good examples. 

As for the .30 example you site, a .30 Carbine usually uses a 110 grain bullet, while a full size rifle usually has something heavier.

If you reload, and were wanting to confuse the issue, you might resize a  125 grain semi jacketed HP.38 and load it in a 9mm case. 

[Sgt. C.J. Sabre, SASS #46770]

9 minutes ago, Abilene Slim SASS 81783 said:

I’d love to see how TV forensics would ID a hollow point plucked from the victim. Hollywood bullets are always so pristine.
 

I haven’t watched a TV cop show all the way through since the 70’s. Has that situation ever come up on these shows?

When they do get a JHP bullet, they tend to be shown in two ways: Either they are fragmented beyond identification, or the computer in the lab can scan the fragments and reconstruct the bullet and ID it. Depending on what the script calls for. Occasionally they are shown with the nose bent over, and the the body intact so they can match rifling.

[Marshal Mo Hare, SASS #45984]

I always used LRN that would 9mm bullets in my .357s

[Abilene Slim SASS 81783]

8 minutes ago, Marshal Mo Hare, SASS #45984 said:

I always used LRN that would 9mm bullets in my .357s

My 9mm rounds are always jacketed because my only 9mm gun is a Glock I use for EDC. 

[sassnetguy50]

3 hours ago, Abilene Slim SASS 81783 said:

I’d love to see how TV forensics would ID a hollow point plucked from the victim. Hollywood bullets are always so pristine.
 

I haven’t watched a TV cop show all the way through since the 70’s. Has that situation ever come up on these shows?

Not a hollow point but it is pristine, the brass stayed on the projectile.

[Pat Riot]

4 hours ago, sassnetguy50 said:

Not a hollow point but it is pristine, the brass stayed on the projectile.

Probably used a wrist rocket slingshot. 

[Alpo]

7 hours ago, Sgt. C.J. Sabre, SASS #46770 said:

or the computer in the lab can scan the fragments and reconstruct the bullet and ID it.

I've always liked that. Almost as much as when they have a photograph of somebody from a high angle, so basically all you see is the top of his head and the tip of his nose, and the computer can tip that photograph back far enough you got a full face and then you can do a facial recognition.

 

Computers can do such wonderful stuff nowadays.

[Pat Riot]

I love it when the cop or coroner states “Looks like a 9mm fired from a Glock”

 

In real life I am sure they could tell the caliber of a bullet extracted from a body. 
 

I wish I could remember what the heck I was watching a couple of years ago but the “victim”(1) had been determined to have been shot with a 9mm. They investigators were baffled because the couldn’t find any “casings”(2) on the ground thus concluding the shooter picked up the “casings” and was probably a skilled assassin. 

At another point it was suggested the shooter may have used a 9mm revolver. A statement was made that the shooter was “truly devious”. I had to laugh at the idiocy of the show and lost interest in it 

 

1. The person shot is always a “victim” in TV shows & movies. 

2. “Casings” are for sausage. 

[Alpo]

I've often thought about, when you go shoot somebody, use the wrong type of bullet. To confuse those forensic scientists.

 

Like shoot somebody with a 77 grain full metal jacket 32 ACP bullet, but load it into a 32 H&R Magnum revolver. Abby will have them looking for a 70-year-old automatic, while Kasie will have them looking for a PPK. 

 

I have a Smith 940 - 9 mm Luger five shot revolver. Uses a moon clip. One day, just for gits and shiggles, I decided to see if I could shoot 380 in it. A 355 bullet is a 355 bullet. And 380 fit in the moon clips. Now the cases expand quite a bit, because 9 mm is a tapered case in 380 is straight, so the back end of a 9 mm a bit bigger around than the back end of a 380.

 

But it will work. So if the world goes to hell and the only thing you can shoot is stuff you can find, and all I can find is 380, I can shoot it in my 9 mm revolver. Good to know.

 

I can shoot 32 automatic in my 32 H&R. Skeeter Skelton said you could shoot it in a 32 Smith & Wesson long, but I have been convinced that the 32 ACP is a bit hotter than a 32 Smith & Wesson long, and therefore it would be equivalent to shooting proof loads. No sense beating up my gun if I don't have to.

 

For that matter, I can shoot 32 acp, 32 smith, 32 Smith long, and 32 H&R in my 30 carbine Blackhawk. I don't know about 327 - I have not looked at the length or the pressures. It might be too long to fit or it might be too hot. Probably not too hot, but it might be.

[El Chapo]

In every firearm murder case I've touched, there has been some circumstantial evidence besides the expended projectiles to tell what caliber of gun was used to kill the victim.  The guy who got his brains blown out by 3 rounds of 00 buck, for example, there were pellets that fell out of his head and landed in the body bag when he got to the medical investigator's office (and more recovered from the body during the autopsy).  If there weren't eye witnesses to the killing and the murderer carrying his Mossberg shotgun before the killing, I suppose someone could have loaded a .32 revolver with round lead balls and blasted him 20+ times, but that didn't seem likely given the evidence.  My understanding is that he took the stand and admitted shooting the victim with the shotgun at the trial and claimed self defense.  He's currently serving a life sentence.

[sassnetguy50]

@Alpo I have compared SAAMI for 327 Fed Mag.  It is shorter, narrower, and higher pressure than 30 Carbine.

[Sgt. C.J. Sabre, SASS #46770]

3 hours ago, Pat Riot said:

I love it when the cop or coroner states “Looks like a 9mm fired from a Glock”

They usually say that they conclude a Glock because the bullet has polygonal marks on it instead of conventional rifling. They seem to never know that older HK pistols had the same thing.

[Alpo]

I like when they look at the brass and say that it was either fired in a Glock or a Beretta.

 

The firing pin hit from a Beretta looks like a round dent. But the firing pin hit from a Glock is a rectangular shape.

 

[Alpo]

1 hour ago, sassnetguy50 said:

@Alpo I have compared SAAMI for 327 Fed Mag.  It is shorter, narrower, and higher pressure than 30 Carbine.

Appreciate it. I guess I won't shoot any 327 in my 30.

 

I never really planned on it, because I see no sense in buying ammunition that I don't have anything chambered in that. But it's nice to know that if I did plan on it, it would be a bad plan.

[Sgt. C.J. Sabre, SASS #46770]

20 minutes ago, Alpo said:

But it's nice to know that if I did plan on it, it would be a bad plan.

Sounds like something you'd try, knowing that it's a bad idea. I want pictures.

[Subdeacon Joe]

1 hour ago, Sgt. C.J. Sabre, SASS #46770 said:

They usually say that they conclude a Glock because the bullet has polygonal marks on it instead of conventional rifling. They seem to never know that older HK pistols had the same thing.

 

That still narrows it down considerably. 

 

Back in '04 there was a double murder on the beach near Jenner,  California. The rifling on the recovered bullets narrowed it to only two makes and models of rifle. Investors then examined the Bound Books of the gun shops and pawn shops in Sonoma and surrounding counties looking for those two types.  Eventually it paid off,  even though the murderer had disposed of the weapon. 

[sassnetguy50]

3 hours ago, Sgt. C.J. Sabre, SASS #46770 said:

They usually say that they conclude a Glock because the bullet has polygonal marks on it instead of conventional rifling. They seem to never know that older HK pistols had the same thing.

As do XDM pistols.

 

From Wikipedia 

"Polygonal rifling prevents the forensic firearms examiner from microscopically measuring the width of land and groove impressions (so-called "ballistic fingerprinting") because the polygonal riflings have a rounded profile instead of well-defined rectangular edges, which causes few noticeable surface deformations. In the FBI GRC file, the land and groove widths for these firearms are listed as 0.000. However, forensic identification of firearms (in court-cases, etc.) is based on microscopic examination of tooling marks on the surface of the bore, produced by the manufacturing process and modified by the drag of bullet jackets on that same surface. Thus, the bore surface of individual firearms is always unique."

 

So a $30 barrel swap and a hammer to the firing pin will defeat the test?

[Sgt. C.J. Sabre, SASS #46770]

1 minute ago, sassnetguy50 said:

So a $30 barrel swap and a hammer to the firing pin will defeat the test?

There was a series of "Men's Adventure" books back in the '80s, (think "The Executioner", "The Destroyer', etc.) who's title character did just that with his 1911 after every fight. Unfortunately my rememberer can't find it right now, but I'll bet one of you guys knows it.

[Subdeacon Joe]

1 hour ago, sassnetguy50 said:

So a $30 barrel swap and a hammer to the firing pin will defeat the test?

 

A couple of passes with some 400 grit sand paper, or an emery board, will do the trick.   Don't forget to hit the inside of the extractor.  Run a Flex-Hone straight in and out of the chamber, don't chuck it into a drill, just straight in and out a few times.

 

Tests on "microstamping" show it to be unreadable after about 50 or 60 rounds. 

[Pat Riot]

5 hours ago, Sgt. C.J. Sabre, SASS #46770 said:

They usually say that they conclude a Glock because the bullet has polygonal marks on it instead of conventional rifling. They seem to never know that older HK pistols had the same thing.

Thing is they never say why they think it’s a Glock. Also, newer Glocks have a more traditional rifling. It’s somewhat rounded but it’s not polygonal. 

[Alpo]

3 hours ago, Sgt. C.J. Sabre, SASS #46770 said:

There was a series of "Men's Adventure" books back in the '80s, (think "The Executioner", "The Destroyer', etc.) who's title character did just that with his 1911 after every fight. Unfortunately my rememberer can't find it right now, but I'll bet one of you guys knows it.

I can't place that book, but Mickey Spillane had Mike Hammer do that with his 1911 in one book (put them both in a 1-quart beer can - I didn't know beer came in one quart cans - and threw the can in the building incinerator), Dog Kelly did that with his 1911 in The Erection Set (buried them in the sand at the beach), and Mike Hammer did it with his secretary Velda's 32 in one book.

[Subdeacon Joe]

1 hour ago, Alpo said:

I can't place that book, but Mickey Spillane had Mike Hammer do that with his 1911 in one book (put them both in a 1-quart beer can - I didn't know beer came in one quart cans - and threw the can in the building incinerator), Dog Kelly did that with his 1911 in The Erection Set (buried them in the sand at the beach), and Mike Hammer did it with his secretary Velda's 32 in one book.

 

 

Both???

 

I can see maybe the barrel if you swap it (run a hone through it instead).  

But I'm thinking that 

4 hours ago, sassnetguy50 said:

hammer to the firing pin

means just tapping the face of it.

[Alpo]

33 minutes ago, Subdeacon Joe said:

Both???

Yes both. The barrel, because the rifling would match with the bullet in the dead guy. And the firing pin because the firing pin dent  on the primer of the three or four cases that he didn't have time to stop and try to pick up.

[El Chapo]

9 minutes ago, Alpo said:

Yes both. The barrel, because the rifling would match with the bullet in the dead guy. And the firing pin because the firing pin dent  on the primer of the three or four cases that he didn't have time to stop and try to pick up.

 

Firearm toolmark is junk science.  In my lifetime, that will no longer be admissible against anyone.  A detailed report came out years ago showing that there has never been a peer reviewed, double blind study demonstrating that looking at scratches on a bullet can uniquely identify the firearm that fired it.  And I'm not even sure the people who believe that is legitimate science would claim that they can do it for a bullet that passed through a person's body.

[Subdeacon Joe]

14 minutes ago, Alpo said:

Yes both. The barrel, because the rifling would match with the bullet in the dead guy. And the firing pin because the firing pin dent  on the primer of the three or four cases that he didn't have time to stop and try to pick up.

 

As I said, a couple of passes with an emery board or sandpaper can deal with the firing pin face.  A couple of passes with a hone will change the machine marks in the barrel. It just has to be different enough to cause doubt. 

[sassnetguy50]

1 hour ago, Subdeacon Joe said:

 

 

Both???

 

I can see maybe the barrel if you swap it (run a hone through it instead).  

But I'm thinking that 

means just tapping the face of it.

No, hit the tip sideways. It is used in the rimfire world to get a good strike on the primer.  

[Sedalia Dave]

Just to muddy the waters a bit.

 

9mm and .38/.357 Barrel Bore Diameters Explained

 

Kinda like how almost all modern 44-40 barrels and 44 Spcl / 44 Mag barrels have the same bore diameter.

[Dapper Dave]

I can tell brass that is fired in a Glock...other than that, I don't know squat, but I can tell you the TV people -can do anything with nothing, because I've seen them pull some FUNNY stuff.

Case in point, Walker, Texas Ranger, he is flying a light plane and is shot down by a guy with an armed P-51 Mustang. Trebet, his partner, goes diving in the ocean to the crash site, and comes up with one pristine bullet...and he waves it in front of the bad guy, "This is a 50 MILLIMETER, the same size as the wing CANNONS in your plane..." I laughed for some time after that.