Topic: Unusual (to me at least) impressions on a bullet

[Brandon Bertolli]

I hope someone can set me on the right path here.


This is a bullet that was recovered from a patient in my PTLGC research (I've posted links to that research elsewhere):

















I suspect it is from a .32ACP cartridge. It was recovered from the patient's chest, whilst I observed the procedure. The surgeon was careful not to mark this bullet.


I have no weight or any measurements, all I did was photograph it.


To me, the marks on the bearing surface are unusual. They aren't the traditional land impressions I would expect to see.
I've seen marks like this on other bullets fired from guns with polygonal rifling, but even in those cases the striations have a left or right twist to them. This looks straight to me, no left or right twist.


Am I right?


If so, could this be from a home-made or improvised weapon?

[Bob Kennington]

Not much to go on.  Normally, I'd hold the base of this bullet to the base of a known 6- or 8-grooved bullet. 'Course, that can't be done remotely.

Are others here seeing a slight twist to the right, and L&G impressions that are relatively narrow? 

The bright (brassy) areas are suggestive of "bore misalignment", which in turn, is suggestive of having been fired in a revolver. (Or fired in a smoothbore—who knows for sure?) 

My mentor and AFTE Member Emeritus , John Sojat, would say the above "observations" were "horseback-opinions". 

[Matthew Kurimsky]

Brandon,
Occasionally in our lab we will see bullets from test fires or evidence that look like your photos. Most of the time its a result of very shallow/ poor quality rifling. Having said that a couple of years ago we had an older 32ACP CZ pistol come in that had no discernible rifling in the BBL at all. It left very, very few marks, in fact you really would have struggled to even say the bullet was fired as opposed to a new or pulled bullet. The interesting thing about that pistol was despite having no visible rifling, it actually shot pretty well (at least out to 25yds).

[Brandon Bertolli]

Thanks all, makes sense now (as a possible explanation of the appearances)

[Robert Thompson]

In Europe and former Soviet countries there are many converted gas guns that are able to fire cartridges from a smooth bore.  I'm not sure of the incidence of them in this caliber, but the bullet sure looks like some of the specimens I have seen in proficiency tests. 

[Brandon Bertolli]

It's a possibility, although this case was from Johannesburg, South Africa.
The bullet struck the man in the region of the left armpit and then moved posteriorly to a palpable position where it could be removed.
I'll post some sneak previews here before I put the case on LinkedIn.

[Aaron Brudenell]

I've seen a number of examples of ordinary conventionally rifled firearms with old and well corroded/worn bores to leave these sorts of fine striated marks over both land and groove impressions alike.  In some cases, the original rifling appears rounded or shallow (both in the gun or on the bullet exterior),  and often those guns will still give the bullet a proper spin and shoot accurately.  The key thing to notice in my experience is evidence of twist and if possible counting/characterizing the original GRC.  If you find neither, then a smooth bore or unrifled gun (possibly home made) is a possibility.   

[Brandon Bertolli]

Is it safe to say then, that it is not possible to say whether the barrel was rifled or not, without having the actual bullet available to inspect it?

[Brandon Bertolli]

As promised, some preview images from PTLGC Case 7...


The wound was in the vicinity of the left armpit:





Here is the bullet being retrieved via a surgical incision:





And a repeat of a previous image, this time including a rule (in mm). That rule was attached to my camera:

[Aaron Brudenell]

Is it safe to say then, that it is not possible to say whether the barrel was rifled or not, without having the actual bullet available to inspect it?

Sometimes the photo and bullet condition make it obvious, this time, while the photos are very good, I would reserve making an opinion until I got to look at the bullet under a stereo scope.

[Bob Kennington]

Is it safe to say then, that it is not possible to say whether the barrel was rifled or not, without having the actual bullet available to inspect it?

I don't think you'll find anyone at AFTE who would give their opinion from photographs.   

A barrel's factory rifling can be affected by wear, corrosion, intentional damage, or misadventure. Barrels have left the factory with no rifling at all!

A case for rifling would be improved by photographing the evidence bullet base-down on a countertop, turning it 180°, and photographing it again. If there was rifling present, it should appear consistent with the same "leaning"—right or left. (Be sure to hang that apparent tab on the base off the counter ).

------------------

My "palpable" moment:
While waiting outside a Florida courtroom on a different case, I was approached by an Assistant State Attorney, who was pushing a wheelchair containing a shooting victim.  I was asked in the hallway if a palpable bullet was consistent with 38 caliber.   

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[Brandon Bertolli]

Thanks all, that is very helpful! I will let you know when I put the whole case online.
Credit will be given to AFTE members for pointing out all the possible causes of these appearances (given the limits of not having access to the bullet).

[Qendrim]

Actually in our Lab I saw and examine a lot of bullets with the similar marks like the bullet in your photo.
Usually we find those kind of bullets (marks on bullet) to the gas or blank pistols made be EKOL who are converted from 9mm gas to .32 (7.65x17mm). So there are not any rifling, but it works to cause a death injury.

[Brandon Bertolli]

That sounds interesting, Qendrim. Are they putting some kind of sleeve in the barrel, or are they only adapting the chamber side to accept .32ACP?


Or do they put some kind of home made sabot around the .32ACP bullet?

[Brandon Bertolli]

I've put the case on LinkedIn here:

https://www.linkedin.com/pulse/ptlgc-case-7-brandon-bertolli