Level of drop safetyness

[sanders]

Hi,

I would like to somehow have a number which represents how drop safe a gun is.
Number would mean the minimum height the gun needs to be dropped from to discharge.

I feel this is a valid question in case of many pistols where there are no safety pin inside as the lack of safety pin means even a decocked gun can discharge accidentally if it is dropped.

In my case I would like to calculate this number about my CZ 75 SP-01 SHADOW gun.

I speak about a minimum height, because the actual angle how the gun touch the ground is important as this fact influence a lot the magnitude of the force pushes firing pin towards the primer. Magnitude would be the highest if the negative acceleration is parallel with the firing pin: this is when the required height is minimal.

To calculate this, I need to know at least
1) the firing pin spring forces in a SP-01 SHADOW gun,
2) maybe the distance the firing pin needs to travel
3) as well as the minimum force average 9mm Luger primer needs to be kicked with to ignite.

My questions:
1) Does anyone knows these parameters? If not, where can I find them?
2) Any experience or advice whatever for the calculation?

Thanks in advance!

[George16]

Ask the manufacturers  .

[Hillbilly357]

Perhaps you would be better suited with a model with a lanyard...

[Dred]

@sanders ...

You will also need 4. mass of firing pin

Sent from my KFMAWI using Tapatalk

[Grendel]

My goodness, the minutae people obsess over never cease to amaze me.

What will you do with the information? How will it affect you? What height would satisfy your criteria? Do you drop your gun often or something? Have there been multiple stories of people dropping their Shadow and blowing a limb off or killing themselves recently or something? Are you in the habit of dropping your gun on a regular basis?

Perhaps trying harder not to drop your pistol is the optimal solution.


(You'd also need to know what surface was used in the drop test, tarmac, concrete, mud, dirt etc, the ambient temperature, and whether it was a straight drop or more of a 'throw').

[MoRivera]

'Safetyness'?

[sanders]

'Safetyness'?

Maybe not the best word for what I mean but hopefully understandable.
This "project" is just about curiosity, of course. Some math and physics but the inputs are missing

[MoRivera]

I gotcha'. 

Tough to quantify in a way that 'rates' everything on an even playing field.  Some models have internal firing pin blocks others don't, how will it be holstered/ready, and so on?  Too many variables so maybe best to have them listed so one can make the decisions themselves in the context of their intended use.

[sanders]

I gotcha'. 

Tough to quantify in a way that 'rates' everything on an even playing field.  Some models have internal firing pin blocks others don't, how will it be holstered/ready, and so on?  Too many variables so maybe best to have them listed so one can make the decisions themselves in the context of their intended use.

I don't want to cover everything. My model is simplified enough.

I suppose
- firing ping can move freely (but there are springs, of course),
- there is no firing pin safety,
- gun is decocked so "normal" way of discharge cannot happen.

I only want to take into consideration the required force which can push forward the firing pin to discharge a round in the chamber.

I neither want to care about the angle how the gun touch the ground. I suppose it is parallel with the firing pin to allow estimation of the minimal height drop can make the necessary force on the primer.

So my math all about a solid body forced to move by the gravity / kinetic energy. In other words, question is that can a solid body (the firing pin) move forward enough to make deformation on another solid body (primer) or not if the "box" (whole gun) where the bodies can move is dropped from a 10 feet height. Answer is not straightforward because of the springs and weights of the bodies. Only parameter in the equation is the height meaning that the potential energy.

[Skookum]

Presumably those states and manufacturers that do drop testing opt for empiricism over modeling for a reason — empirical testing is more reliable.  However, the SIG Sauer P320 is proof that even extensive empiricism isn't comprehensive.  And, this incident shows no sidearm is completely drop safe, as a powerful magnet, which caused a horizontal "drop," was able to simultaeously overcome the slide lock safety, the grip safety, the firing pin block, and the firing pin spring on a Colt 1991A1 to cause a discharge:

https://www.ajronline.org/doi/full/10.2214/ajr.178.5.1781092

[MoRivera]

I gotcha'. 

Tough to quantify in a way that 'rates' everything on an even playing field.  Some models have internal firing pin blocks others don't, how will it be holstered/ready, and so on?  Too many variables so maybe best to have them listed so one can make the decisions themselves in the context of their intended use.

I don't want to cover everything. My model is simplified enough.

I suppose
- firing ping can move freely (but there are springs, of course),
- there is no firing pin safety,
- gun is decocked so "normal" way of discharge cannot happen.

I only want to take into consideration the required force which can push forward the firing pin to discharge a round in the chamber.

I neither want to care about the angle how the gun touch the ground. I suppose it is parallel with the firing pin to allow estimation of the minimal height drop can make the necessary force on the primer.

So my math all about a solid body forced to move by the gravity / kinetic energy. In other words, question is that can a solid body (the firing pin) move forward enough to make deformation on another solid body (primer) or not if the "box" (whole gun) where the bodies can move is dropped from a 10 feet height. Answer is not straightforward because of the springs and weights of the bodies. Only parameter in the equation is the height meaning that the potential energy.

But then what's the plausible application/use that would benefit from that knowledge and comparison, aside from recreating your test parameters to the detail?

[sanders]

But then what's the plausible application/use that would benefit from that knowledge and comparison, aside from recreating your test parameters to the detail?

Curiosity. Science.

[sanders]

Presumably those states and manufacturers that do drop testing opt for empiricism over modeling for a reason — empirical testing is more reliable.  However, the SIG Sauer P320 is proof that even extensive empiricism isn't comprehensive.  And, this incident shows no sidearm is completely drop safe, as a powerful magnet, which caused a horizontal "drop," was able to simultaeously overcome the slide lock safety, the grip safety, the firing pin block, and the firing pin spring on a Colt 1991A1 to cause a discharge:

https://www.ajronline.org/doi/full/10.2214/ajr.178.5.1781092

Thanks for the link! It was an interesting reading!

[BBF97]

'Safetyness'?

Maybe not the best word for what I mean but hopefully understandable.
This "project" is just about curiosity, of course. Some math and physics but the inputs are missing

Generally "Margin of Safety", "Safety Margin" etc. Yet the calculations won't tell you much of anything. Unless you do a tolerance analysis and we don't know the tolerances of these vendors. 2nd, friction coefficients are notoriously difficult to determine.

Why you are doing this is an important question.

[BBF97]

Presumably those states and manufacturers that do drop testing opt for empiricism over modeling for a reason — empirical testing is more reliable.  However, the SIG Sauer P320 is proof that even extensive empiricism isn't comprehensive.  And, this incident shows no sidearm is completely drop safe, as a powerful magnet, which caused a horizontal "drop," was able to simultaeously overcome the slide lock safety, the grip safety, the firing pin block, and the firing pin spring on a Colt 1991A1 to cause a discharge:

https://www.ajronline.org/doi/full/10.2214/ajr.178.5.1781092

It is not evident that impact caused the discharge. Could have or could be in tandem with magnetic forces. Guy who took gun into a room - which are all heavily marked NO MAGNETIC MATERIALS PERMITTED - needs an MRI