JFK Assassination Plus General Discussion & Debate > JFK Assassination Plus General Discussion And Debate
Dr. E. Forrest Chapman
Jack Nessan:
--- Quote from: Charles Collins on June 11, 2026, 11:22:20 PM ---
Thanks Jack, I don’t remember seeing a second row of images in the Kindle version of the book that I purchased recently. I have been researching further trying to understand more about the action of the Carcano rifle. Below please find a Q&A that I think might be pertinent.
For what it is worth:
Question to Google AI:
if the bolt handle of a Carcano model 91-38 rifle is slightly not completely down in the closed position can the trigger still be pulled and the rifle fire and if so, can this cause a variation in the depth of the firing pin depression in the primer of the cartridge?
Google AI answer:
Yes, a Carcano Model 91/38 can be fired with the bolt handle slightly unlatched. Because of the design of the cocking cams, pulling the trigger releases the firing pin even if the bolt is not fully locked down.
The Mechanics:
Trigger Pull and Firing: Most bolt-action rifles are designed with an "out of battery" safety that disconnects the sear or physically blocks the firing pin if the bolt is not fully closed. However, the historic Carcano M91 design lacks this modern feature. When the bolt handle is slightly raised:The trigger can still be pulled, releasing the cocking piece and firing pin. As the firing pin drives forward, its energy is often spent camming the bolt handle downward into the locked position before the pin hits the primer. Alternatively, if the bolt is held firmly in place so it cannot self-close, the firing pin will release and strike the primer while the bolt remains partially out of battery.
Effect on Firing Pin Depth (Primer Indentation):
If the bolt fails to fully lock down, it fundamentally alters the headspacing of the firearm. When the trigger is pulled:Inconsistent Depth: You will likely notice a variation in the depth of the firing pin depression. If the firing pin's forward energy is robbed by the effort of forcing the bolt to cam into battery, the indent will often be shallow, light, or off-center.
Safety Risks: Firing a rifle "out of battery" (when the bolt lugs are not fully seated and locked into the receiver) is extremely dangerous. It exposes the unsupported or partially supported cartridge case to high pressures, which can cause ruptured brass, blown primers, and escaping gas that could damage the firearm or injure the shooter.
For more context on how these components function, you can view the Carcano Bolt Disassembly and Reassembly guide.
--- End quote ---
I guess it depends on which AI is being used. This is COPILOT.
JN “can a M38 carcano rifle be discharged without the bolt fully closed”
Short answer: No. An M38 Carcano cannot discharge unless the bolt is fully closed and locked. This is a hard mechanical rule of the Carcano action — not something that varies by model.
🔧 Why the M38 cannot fire out of battery
The M38 uses the same fundamental Carcano turn‑bolt system as the M91/38 and earlier long rifles. Three mechanical interlocks prevent firing unless the bolt is fully rotated down:
1. Front locking lugs
The firing pin cannot reach the primer unless the bolt lugs are fully engaged in their recesses. If the bolt is even slightly up, the lugs block firing‑pin travel.
2. Firing‑pin cam block
The cam track on the bolt body physically stops the firing pin from moving forward until the bolt handle is fully down. This is a positive mechanical stop, not a soft interference.
3. Cocking piece/sear alignment
The sear only releases the cocking piece when the bolt is in the locked position. If the bolt is not fully closed, the trigger may “click,” but the firing pin cannot travel.
🧪 What happens if you try to fire with the bolt slightly open
On a Carcano (including the M38):
The trigger can release the cocking piece.
The firing pin begins to move forward.
The cam block stops it before it reaches the primer.
Result: a dry click, no ignition.
There is no known case — in military testing, civilian use, or forensic examination — of a Carcano firing out of battery.
---------------------------
It looks like the difference is really does the firing pin release even though you are hearing the click. One AI says it does the other says it does not. The ones I messed with I could not tell. I did notice when the bolt is rotated and the spring is engaged the bolt can no longer move and is tight to the chamber.
Jack Nessan:
--- Quote from: Lance Payette on June 11, 2026, 11:42:23 PM ---FWIW, the firing pin impression issue was addressed by Donald Champagne at page 455 of the HSCA firearms panel's testimony.
https://aarclibrary.org/publib/jfk/hsca/reportvols/vol1/pdf/HSCA_Vol1_0908_6_Firearms.pdf
This is HSCA Figure 21A, "Photomicrograph showing the correspondence between the individual identifying characteristics on the CE 543 cartridge case (L) and on panel Kennedy T-1 (R), produced by the firing pin of the CE 139 rifle." Hmm ... does the indentation on CE 543 (L portion) not look somewhat different, along the lines of what Chapman was talking about?
--- End quote ---
Lance, good eye, this is a really good point. CE 543 is not only slightly dished in, but the firing pin impression is a little “larger”, as described by Dr. Chapman, or wider from multiple firing pin strikes. That would make sense from the stand point chambers are a little bigger than shell casings for ease of introduction of the cartridge and extraction of the shell casing. What that means is the shell casing can be slightly loose in the chamber and on the bolt, especially without a bullet to help center it. Basically, the shell can be a little off center in the bolt.
Dr. Chapman mentions this himself in his observations.
Dr. Chapman noticed that the indentation on the CE 543 primer was larger than the indentations on the other shell casings found in the sniper's nest.
Dr Chapman is describing a wider firing pin impression. Really, nice work Lance.
Jack Nessan:
--- Quote from: John Corbett on June 12, 2026, 01:46:43 AM ---Do you think eyewitnesses would have seen a missed shot?
--- End quote ---
I am sure they would have heard one. Not one person, crowd or cars, reacted to anything at Z150 or whatever it is this week. Maybe it is time to update from this failed theory.
Charles Collins:
Here’s an interesting animation showing how the Carcano action works:
//www.youtube.com/watch?v=NJjg-U9DJqs
Charles Collins:
--- Quote from: Jack Nessan on June 12, 2026, 04:14:05 AM ---I guess it depends on which AI is being used. This is COPILOT.
JN “can a M38 carcano rifle be discharged without the bolt fully closed”
Short answer: No. An M38 Carcano cannot discharge unless the bolt is fully closed and locked. This is a hard mechanical rule of the Carcano action — not something that varies by model.
🔧 Why the M38 cannot fire out of battery
The M38 uses the same fundamental Carcano turn‑bolt system as the M91/38 and earlier long rifles. Three mechanical interlocks prevent firing unless the bolt is fully rotated down:
1. Front locking lugs
The firing pin cannot reach the primer unless the bolt lugs are fully engaged in their recesses. If the bolt is even slightly up, the lugs block firing‑pin travel.
2. Firing‑pin cam block
The cam track on the bolt body physically stops the firing pin from moving forward until the bolt handle is fully down. This is a positive mechanical stop, not a soft interference.
3. Cocking piece/sear alignment
The sear only releases the cocking piece when the bolt is in the locked position. If the bolt is not fully closed, the trigger may “click,” but the firing pin cannot travel.
🧪 What happens if you try to fire with the bolt slightly open
On a Carcano (including the M38):
The trigger can release the cocking piece.
The firing pin begins to move forward.
The cam block stops it before it reaches the primer.
Result: a dry click, no ignition.
There is no known case — in military testing, civilian use, or forensic examination — of a Carcano firing out of battery.
---------------------------
It looks like the difference is really does the firing pin release even though you are hearing the click. One AI says it does the other says it does not. The ones I messed with I could not tell. I did notice when the bolt is rotated and the spring is engaged the bolt can no longer move and is tight to the chamber.
--- End quote ---
That’s interesting Jack, thanks.
What seems preposterous to me about the dry-firing theory is that: if an empty cartridge were to be used for dry fire and the firing pin struck the primer for a second time, I believe that the initial impressions stamped into the primer by the firing pin when the live bullet was fired would be obliterated such that an identification would not be feasible.
Have you taken any of the test cartridges that you dry-fired to a firearms expert and asked if they could be identified as being fired from the rifle you used?
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