.50BMG explodes with serious injuries.

Bolt action rifles, lever action, pump action, self loading rifles and other miscellaneous longarms.

.50BMG explodes with serious injuries.

Post by bladeracer » 30 Apr 2021, 4:21 pm

https://www.youtube.com/watch?v=1449kJKxlMQ&t=1027s

Kentucky Ballistics had a serious ammo issue.
Practice Strict Gun Control - Precision Counts!
User avatar
bladeracer
Field Marshal
Field Marshal
 
Posts: 12655
Victoria

Re: .50BMG explodes with serious injuries.

Post by Tubs » 30 Apr 2021, 4:45 pm

Holy Smokes! Action starts at 4 min:20
Tubs
Corporal
Corporal
 
Posts: 306
New South Wales

Re: .50BMG explodes with serious injuries.

Post by in2anity » 30 Apr 2021, 4:51 pm

Double charge I bet
At what point does lack of maintenance become patina?
User avatar
in2anity
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 3048
New South Wales

Re: .50BMG explodes with serious injuries.

Post by Tubs » 30 Apr 2021, 4:55 pm

in2anity wrote:Double charge I bet


Should of stuck with Trailboss dammit
Tubs
Corporal
Corporal
 
Posts: 306
New South Wales

Re: .50BMG explodes with serious injuries.

Post by bladeracer » 30 Apr 2021, 5:10 pm

in2anity wrote:Double charge I bet


I really doubt it's possible to get 500gn into a .50BMG case :-)
More likely the wrong powder was used if it was handloaded.

I was surprised when he suggested the rounds might actually be handloads from somewhere, don't know that I'd be game shooting somebody else's handloads with 250gn+ charges.
Practice Strict Gun Control - Precision Counts!
User avatar
bladeracer
Field Marshal
Field Marshal
 
Posts: 12655
Victoria

Re: .50BMG explodes with serious injuries.

Post by No1Mk3 » 30 Apr 2021, 5:16 pm

Very serious, lucky man! It defines the issue of shooting unknown ammo though, I recall a young fellow a couple of years ago getting a bolt in his face when using someone's unknown reloads.
No1Mk3
Second Lieutenant
Second Lieutenant
 
Posts: 2090
Victoria

Re: .50BMG explodes with serious injuries.

Post by Bill » 30 Apr 2021, 5:44 pm

Develop your own loads and thoroughly check any action before firing, that guy is one lucky goose to be still alive

A fella I meet a few years ago lost his left thumb as someone had decide to decommission a 303 with a drill into the action, unfortunately below the timber line and he hadnt been informed.
When a guy is digging his own grave, you don’t fight him for the shovel.

Success leaves clues, Fools follow failure !

20 Hornet, 218 Bee, 222 Rem, 256 WM, 6mm ARC, 6.5 Grendel, 6.5x55 Scan, 270 Win, 357 Mag, 358 Win, 9.3x62, 500 A Square
User avatar
Bill
Warrant Officer C1
Warrant Officer C1
 
Posts: 1253
New South Wales

Re: .50BMG explodes with serious injuries.

Post by disco stu » 30 Apr 2021, 5:56 pm

Wowsers!! Blessed man indeed
disco stu
Sergeant
Sergeant
 
Posts: 526
New South Wales

Re: .50BMG explodes with serious injuries.

Post by Bugman » 30 Apr 2021, 6:21 pm

Lucky to be alive, which is good.
User avatar
Bugman
Warrant Officer C2
Warrant Officer C2
 
Posts: 1071
New South Wales

Re: .50BMG explodes with serious injuries.

Post by Tiger650 » 30 Apr 2021, 7:27 pm

Many yrs back I read that the Bundeswehr [West German Army] had at one time had to condemn their locally loaded .5" ammo due to sabotage at point of manufacture.
The detonating cartridges were said to be light charges of fast powder.
Possibly 7.62 x 51 propellant ?
The Stasi may have reached across time and f4C*ed this bloke up.
The Yanks did much the same thing in Vietnam, uncover a cache of small arms ammo and load some rds with high explosive so SKS or AK go boom backwards/sideways.
Not good for morale when comrade loses half his head, guaranteed to generate flinch.
Tiger650
Corporal
Corporal
 
Posts: 451
Victoria

Re: .50BMG explodes with serious injuries.

Post by in2anity » 30 Apr 2021, 8:51 pm

bladeracer wrote:
in2anity wrote:Double charge I bet


I really doubt it's possible to get 500gn into a .50BMG case :-)
More likely the wrong powder was used if it was handloaded.

I was surprised when he suggested the rounds might actually be handloads from somewhere, don't know that I'd be game shooting somebody else's handloads with 250gn+ charges.


Yeah you’re probably right Blade - wrong (too fast) powder. I wonder how it would have faired in a traditional bolt action?
At what point does lack of maintenance become patina?
User avatar
in2anity
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 3048
New South Wales

Re: .50BMG explodes with serious injuries.

Post by wanneroo » 01 May 2021, 12:03 am

bladeracer wrote:
I really doubt it's possible to get 500gn into a .50BMG case :-)
More likely the wrong powder was used if it was handloaded.

I was surprised when he suggested the rounds might actually be handloads from somewhere, don't know that I'd be game shooting somebody else's handloads with 250gn+ charges.


Yeah I sure as hell wouldn't be shooting someone's handloads in that thing. Wouldn't be shooting it at all really, looks too weak for me, if something goes wrong the pressure has nowhere to go except a kaboom.
wanneroo
Warrant Officer C1
Warrant Officer C1
 
Posts: 1412
United States of America

Re: .50BMG explodes with serious injuries.

Post by MontyShooter » 01 May 2021, 8:34 am

Every gun will go kaboom if the expanding gasses have nowhere to go
MontyShooter
Corporal
Corporal
 
Posts: 339
Victoria

Re: .50BMG explodes with serious injuries.

Post by No1_49er » 01 May 2021, 11:48 am

Very true, but the Kentucky Ballistics shooter explained, quite clearly, that the previous round that he fired at the old fire hydrant did indeed leave the barrel and he extracted it from the hole in the hydrant. Ergo, the barrel was not blocked.
Proud member of "the powerful gun lobby" of Australia :)
No1_49er
Staff Sergeant
Staff Sergeant
 
Posts: 823
Queensland

Re: .50BMG explodes with serious injuries.

Post by on_one_wheel » 01 May 2021, 11:56 am

Pretty nasty looking action, screw on cap with 2 pissy lugs behind it. I guess its a budget 50cal rig?
Gun control requires concentration and a steady hand
User avatar
on_one_wheel
Colonel
Colonel
 
Posts: 3561
South Australia

Re: .50BMG explodes with serious injuries.

Post by Blr243 » 01 May 2021, 12:12 pm

I tend to agree one wheel. Looks like the sort of thing a backyard jamacain gangster might do with pipe And fittings from mitre ten
Blr243
Brigadier
Brigadier
 
Posts: 4479
Queensland

Re: .50BMG explodes with serious injuries.

Post by on_one_wheel » 01 May 2021, 12:30 pm

:lol: that's basically what I was thinking
When he was talking pressures, I thought that the design wasn't leaving much room for a safety factor.

Catastrophic failure :shock:
Gun control requires concentration and a steady hand
User avatar
on_one_wheel
Colonel
Colonel
 
Posts: 3561
South Australia

Re: .50BMG explodes with serious injuries.

Post by in2anity » 01 May 2021, 12:30 pm

Blr243 wrote:I tend to agree one wheel. Looks like the sort of thing a backyard jamacain gangster might do with pipe And fittings from mitre ten

:lol:
At what point does lack of maintenance become patina?
User avatar
in2anity
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 3048
New South Wales

Re: .50BMG explodes with serious injuries.

Post by on_one_wheel » 01 May 2021, 12:43 pm

Next time he tests a breach loading pipe bomb he might want to were something to better protect himself from the blast.
20210501_121109.jpg
20210501_121109.jpg (58.21 KiB) Viewed 7764 times
Gun control requires concentration and a steady hand
User avatar
on_one_wheel
Colonel
Colonel
 
Posts: 3561
South Australia

Re: .50BMG explodes with serious injuries.

Post by Blr243 » 01 May 2021, 1:09 pm

Do people who wear suits like that , bomb deactivation experts, get grey hair 20 years earlier than everyone else ? Not my idea of an ideal job
Blr243
Brigadier
Brigadier
 
Posts: 4479
Queensland

Re: .50BMG explodes with serious injuries.

Post by in2anity » 01 May 2021, 1:16 pm

Hurt Locker is one of the best
At what point does lack of maintenance become patina?
User avatar
in2anity
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 3048
New South Wales

Re: .50BMG explodes with serious injuries.

Post by on_one_wheel » 01 May 2021, 1:21 pm

"Normal" or working pressure = ~55,000psi
Manufacturers estimated yeild point >85,000psi

Using the pressures given in the video, If my calculations are correct, That's an additional 55% pressure, giving .5 (point 5) designed margin of safety for that particular firearm.

I would have thought that firearms would have a much larger margin of safety than that.
It would be interesting to look at what margin of safety is built into some of our popular firearms.
Gun control requires concentration and a steady hand
User avatar
on_one_wheel
Colonel
Colonel
 
Posts: 3561
South Australia

Re: .50BMG explodes with serious injuries.

Post by on_one_wheel » 01 May 2021, 3:56 pm

Blr243 wrote:Do people who wear suits like that , bomb deactivation experts, get grey hair 20 years earlier than everyone else ? Not my idea of an ideal job


I bet they do, as well as developing a stutter, having uncontrollable nervous shakes and sleep paralysis... no thanks.
Gun control requires concentration and a steady hand
User avatar
on_one_wheel
Colonel
Colonel
 
Posts: 3561
South Australia

Re: .50BMG explodes with serious injuries.

Post by No1_49er » 03 May 2021, 8:11 pm

Especially for you, right here in Oz, going cheap https://usedguns.com.au/gun/356388/
Maybe the owner saw the video and decided to bail.
Proud member of "the powerful gun lobby" of Australia :)
No1_49er
Staff Sergeant
Staff Sergeant
 
Posts: 823
Queensland

Re: .50BMG explodes with serious injuries.

Post by on_one_wheel » 03 May 2021, 9:54 pm

$3000!!!! Tell him his dreaming
Gun control requires concentration and a steady hand
User avatar
on_one_wheel
Colonel
Colonel
 
Posts: 3561
South Australia

Re: .50BMG explodes with serious injuries.

Post by NTSOG » 04 May 2021, 7:03 am

Ian McCollum has a done a follow up review after seeing the video of the .50BMG explode:

https://www.forgottenweapons.com/earth- ... s-explode/

Jim
NTSOG
Sergeant
Sergeant
 
Posts: 555
Victoria

Re: .50BMG explodes with serious injuries.

Post by straightshooter » 04 May 2021, 7:58 am

on_one_wheel wrote:"Normal" or working pressure = ~55,000psi
Manufacturers estimated yeild point >85,000psi

Using the pressures given in the video, If my calculations are correct, That's an additional 55% pressure, giving .5 (point 5) designed margin of safety for that particular firearm.

I would have thought that firearms would have a much larger margin of safety than that.
It would be interesting to look at what margin of safety is built into some of our popular firearms.

Ackley's book details destructive tests on various actions, mostly ex military,
The Serbu RN-50 is an extremely cheaply made firearm that relies on a hand threaded end cap for breech containment.
I suspect that the designer, Professor Bubba, had little to no idea of the behaviour of threaded joints under stress.
Also in the US proof testing seems to be at the whim of the manufacturer.
Note the phrase "Manufacturers estimated yield point >85,000psi"
"Anything is possible if you don't know what you are talking about."
"There is no expedient to which a man will not resort to avoid the real labor of thinking." Sir Joshua Reynolds
straightshooter
Warrant Officer C1
Warrant Officer C1
 
Posts: 1263
New South Wales

Re: .50BMG explodes with serious injuries.

Post by InisBineest » 04 May 2021, 8:08 am

While I'm sure those making such assertions about the poor design of the RN-50 are highly qualified gunsmiths and engineers.... May I suggest folks watch an analysis from a well known firearms expert on the incident that they might find interesting/educating.

https://youtu.be/bBNHI1_urWs
InisBineest
Corporal
Corporal
 
Posts: 257
Victoria

Re: .50BMG explodes with serious injuries.

Post by straightshooter » 04 May 2021, 9:16 am

I watched the video by your 'well known firearms expert' and am somewhat underwhelmed.
It is a fairly good example of motivated reasoning in as much as only facts that support his 'educated guess' were presented and his immediate assertion that the failure was due to a single massive overload.
Now consider this.
The end cap is hand threaded onto the end of the barrel, technically it does not have any preload. It is thus loosely attached to the thread.
Each time a cartridge is fired an impact load is applied to the threaded joint with the possibility of localised thread deformations due to the looseness of the joint.
Eventually a buildup of these deformations can lead to catastrophic failure.
Now try to imagine tearing a thick phone book in half. Once upon a time a popular demonstration of strength. In reality the strongest muscleman was unable to tear the phone book when the book was in it's normal state. The trick was to splay the pages slightly so that pages commenced tearing one at a time and once started offered little further resistance.
That is comparable to what I suspect was the failure mode in this instance.
Somebody babbling their opinions on a youtube video does not automatically promote them to 'expert' status.
Nor am I an expert, but I am happy to sometimes offer my opinion.
"Anything is possible if you don't know what you are talking about."
"There is no expedient to which a man will not resort to avoid the real labor of thinking." Sir Joshua Reynolds
straightshooter
Warrant Officer C1
Warrant Officer C1
 
Posts: 1263
New South Wales

Re: .50BMG explodes with serious injuries.

Post by bladeracer » 04 May 2021, 9:34 am

straightshooter wrote:
on_one_wheel wrote:"Normal" or working pressure = ~55,000psi
Manufacturers estimated yeild point >85,000psi

Using the pressures given in the video, If my calculations are correct, That's an additional 55% pressure, giving .5 (point 5) designed margin of safety for that particular firearm.

I would have thought that firearms would have a much larger margin of safety than that.
It would be interesting to look at what margin of safety is built into some of our popular firearms.

Ackley's book details destructive tests on various actions, mostly ex military,
The Serbu RN-50 is an extremely cheaply made firearm that relies on a hand threaded end cap for breech containment.
I suspect that the designer, Professor Bubba, had little to no idea of the behaviour of threaded joints under stress.
Also in the US proof testing seems to be at the whim of the manufacturer.
Note the phrase "Manufacturers estimated yield point >85,000psi"


Not an estimated yield, that is the calculated yield of that thread dimension in that material.
Mark Serbu is well aware of the properties of the materials he uses.
A 50BMG proof round only increases pressure from 64,000psi to 75,000psi, +17% over design pressure. The threaded joint was designed to withstand 85,000psi, so the pressure was higher than that. I don't think anybody can claim that that cartridge was within design pressures.

These rounds sell for US$100 apiece, thus people fabricate them for profit. I don't know if forensic testing can determine the specific propellant that was burned, but I think that is the suspect. With the shortages in the US currently, somebody probably just filled a case with whatever powder they could find and sold it on.
Practice Strict Gun Control - Precision Counts!
User avatar
bladeracer
Field Marshal
Field Marshal
 
Posts: 12655
Victoria

Next

Back to top
 
Return to Centerfire rifles