? on exterior ballistics on a squib load with two bullets leaving barrel

[NukemJim]

(Mods please move this if another section is more appropriate)

A question please for those more knowledgable than I. This question is was sparked by a NCIS episode.

If you have a squib load where where the first bullet is stuck in the barrel and then a second round (not a squib load) is fired which pushes both bullets out of the barrel do the bullets wind up having the same velocity or two different velocities. Supposedly the firearm in question was a 9mm semiautomatic.

I realize that this is much more of a theoretical question than an actual question, after all who is going to purposely make a gun have a bullet stuck in the barrel and then use a chronograph while firing another round, thereby risking destroying the gun, the chronograph and possibly injuring/killing the shooter. Not even sure a chronograph could measure two projectiles so close together.

Anyone with knowledge about this please respond. Thank you, NukemJim

 

[bdickens]

Hollywood is fake.

 

[PapaG]

#1. TV is no better than Hollywood for truth and accuracy regarding firearms.
#2. A "squib" , which used to be a term that referred to a lightly loaded gallery or target load but now has come to mean a "stuck" in barrel load is an obstruction.
#3. When a properly loaded cartridge is fired with a bullet lodged in the barrel one of several things will happen: the barrel will split, bulge or otherwise be ruined. The stuck bullet may be driven out of the barrel but damage will occur.
Many old gallery guns from county fairs and carnivals have one or more bulges from the second bullet hitting a stuck projectile.
TV, Hollywood producers know no more about guns than politicians and leftists.

 

[Shanvanvocht]

Julian Hatcher devoted an entire chapter in Hatcher's Notebook to "Experiments with Barrel Obstructions"

 

[edwardware]

I second the suggestion to read Hatcher's.

They will have the same velocity, likely stuck together, but. . .often neither bullet leaves the barrel, leading to a kaboom (or the more boring bulged barrel) instead of a shooting.

 

[NukemJim]

I have read Hatcher but do not recall him mentioning this situation. However I read him decades ago and my copy is currently in storage.

 

[lysanderxiii]

(Mods please move this if another section is more appropriate)

A question please for those more knowledgable than I. This question is was sparked by a NCIS episode.

If you have a squib load where where the first bullet is stuck in the barrel and then a second round (not a squib load) is fired which pushes both bullets out of the barrel do the bullets wind up having the same velocity or two different velocities. Supposedly the firearm in question was a 9mm semiautomatic.

I realize that this is much more of a theoretical question than an actual question, after all who is going to purposely make a gun have a bullet stuck in the barrel and then use a chronograph while firing another round, thereby risking destroying the gun, the chronograph and possibly injuring/killing the shooter. Not even sure a chronograph could measure two projectiles so close together.

Anyone with knowledge about this please respond. Thank you, NukemJim

What is going to happen to the pressure when the mass of the projectile suddenly doubles when the second bullet runs into the first bullet?

Hint: Nothing good.

See Hatcher page 194-196.

 

[230RN]

I have read Hatcher but do not recall him mentioning this situation. However I read him decades ago and my copy is currently in storage.

He relates anecdotally an example where all six bullets got stuck in a revolver barrel. Bear in mind a lot of pressure can be relieved because of the cylinder gap.

He also tells of several bullets being stuck in a .22 rifle barrel. And several experiments in the service rifle with stuck bullets. Ordnance discovered that firing a cartridge behind it with the bullet removed blew the stuck bullet out quite handily without harm and they thought "it was a method worthy of recommendation."

However, he mentioned, it was not known what would happen in unusual circumstances so the method was not distributed.

He noted that the problem with bulged barrels resulted because the impact energy of the following bullet would expand both sideways. He also noted that there was a machine gun with a badly bulged barrel which shot quite well, and several instances where the bullet core blew out, leaving the jacket stuck in the bore. The following shots just pressed the jacket into the bore resulting in a bulged barrel. (This was due to people removing the tips of FMJ bullets to make them into expanding bullets.)

But there were often other surprising results in Ordnance's experiments.

This was in Hatcher's Notebook; perhaps you were reading another of his books.

Terry, 230RN

 

[Archie]

Reading Hatcher is always appropriate.
I have seen photos of older revolvers and one 'remainder' of a .32-20 revolver with a number of bullets in the barrel. They were visible, as the barrel split - not explode - on the sixth round. (The arm was reasonable retired from use.)
I agree with the OP, I will not intentionally do this. It's revolting to me to intentionally damage much of anything, especially a firearm.

All that aside, I cannot comprehend how one projectile - in such a circumstance - could have a meaningful difference in velocity, provided the projectiles were the same mass. Further I would expect the velocity to be somewhat less than the norm.
Read Hatcher.

 

[PapaG]

I have had numerous guns come in the shop with stuck bullets, usually owned by new reloaders who reasoned if starting loads are good, lower loads ought to be safer.
Worst example was a stainless Ruger Blackhawk with three unfired rounds in the cylinder one stuck between cylinder and barrel and two jammed ahead of that one.
I figured that the cylinder gap released enough pressure that nothing blew. Getting it apart is a whole article in itself.
Several snobby revolvers with one round in the barrel, one .243 with one stuck midway, several with bulges and owners wondering if I could "forge" the bulge back down and reblue

 

[Speedo66]

I have read accounts of soldiers in the Civil War picking up a muzzle loading rifle or musket from a fallen comrade and loading it, not realizing it was already loaded. Supposedly there were instances where several bullets were already loaded.

I can only imagine what firing that would result in.

 

[Jim Watson]

I cannot see a means that would give the stuck bullet and the "driving" bullet different velocities.
"Lieutenant Bush, have the guns double-shotted." "Aye aye, Captain Hornblower, sir."

An unusual occurrence that I witnessed, a co-worker wanted light loads but he did not want to dirty up his .38 with nasty old waxed lead wadcutters. So he put up some Speer 158 gr JSPs over a wadcutter level powder charge. A few fired normally, then one didn't. We did not notice a strange report through earplugs and it did make a hole in the target. So he kept shooting. When he got home and cleaned his revolver, he found that the patch "jumped" halfway down. Yup, a bulge.
We went back to the range and dug in the berm.
We found:
A lead rod, the bullet core that had made the hole in the target.
A bullet jacket, packed with cardboard, that had been pushed through the target by the "driving" bullet, its base indented by the nose of the "driving" bullet.
The "driving" bullet with exposed lead nose formed to the shape of the dished in jacket base.
Apparently what happened was that the high friction and low velocity of the original bullet's copper jacket in steel barrel inertia pulled the core which continued downrange, leaving the jacket stuck in the bore. The next shot blew it out and ring bulged the barrel. S&W replaced it for a reasonable fee.

Stuck bullets in .22s are common, I drove one out of a friend's Glock 44 last month.
My first revolver about age 15 was a S&W Combat Masterpiece .22. My Dad and I were at the dealer when I noticed it on the shelf behind the display counter. I asked "How about that one?" The dealer said "It was traded in and when we cleaned it to put it out for sale, we found a bulge in the barrel. We are going to send it in for a new barrel." I said "Hey, Pa, can we have them call us when it comes back?" He agreed, and bought it for me. Still one of my favorites 62 years down the way. It is now kind of two-toned because it is a 1953 with the post war dull blue and the 1960 replacement barrel is highly polished.

And several experiments in the service rifle with stuck bullets. Ordnance discovered that firing a cartridge behind it with the bullet removed blew the stuck bullet out quite handily without harm and they thought "it was a method worthy of recommendation."

However, he mentioned, it was not known what would happen in unusual circumstances so the method was not distributed.

There is or was a poster right here who said that when a customer brought in a gun with stuck bullet he told him, "I will try to get it out, come back tomorrow." He waited until the customer was out of earshot, pulled a bullet, and blew the offending projectile right out.

Hatcher did try some of those unusual circumstances and found that a bullet stuck at the muzzle would induce a bulge right at the worst spot. Non-bullet obstructions like the attempt to use a hat cord as pull through (We hear of stuck Bore Snakes these days.) or a stuck patch or chewing gum (!) behaved strangely and unpredictably.

 

[Remington1911]

I have had numerous guns come in the shop with stuck bullets, usually owned by new reloaders who reasoned if starting loads are good, lower loads ought to be safer.
Worst example was a stainless Ruger Blackhawk with three unfired rounds in the cylinder one stuck between cylinder and barrel and two jammed ahead of that one.
I figured that the cylinder gap released enough pressure that nothing blew. Getting it apart is a whole article in itself.
Several snobby revolvers with one round in the barrel, one .243 with one stuck midway, several with bulges and owners wondering if I could "forge" plot back down and reblue

I think I posted up a thread on what happened when I came across a 38 revolver that I had stored loaded, but had been "soaked" with Ballastol. Gun sat for about 5 years, and when I went to shoot the first round was normal, the second felt soft, the third squib I had to drill out. When the rest of the bullets got pulled the powder was like mud, figured the ballastol soaked in and ruined the powder.

Had to drill the bullet out, not bad, lead is very soft.

 

[230RN]

The part I described in Hatcher was when a bullet was stuck part way up the barrel, and a subsequent fired bullet had gathered some kinetic energy and impacted the stuck bullet, resulting in the spreading out and bulging of the barrel. Sometimes the barrel would split from the spreading out ("upsetting") of the bullets, sometimes not,

Where a bullet was stuck in the bore right near the chamber ("double shot the cannons"), both may be blown out with very high pressure, but without actual damage to the barrel.

I point out, in addition, the ultimate pressure of black powder (as in double-shotted cannon) is only about 20 tons.* This is where a container absolutely full of black powder is strong enough to take all of the pressure when it is ignited. Compare this to the normal service rifle pressure of ~55,000 psi and the proof round of ~70,000 psi.**


Hatcher, in the form of the Ordnance Dept, performed many many experiments with barrel obstructions since the "hat cord" cleaning implement could pull, but not push. They found, for example, that a light steel cap would not affect pressure at all, since the bullet could easily pierce the sheet metal.

Terry, 230RN

*Page 116, "Gunpowder" by Jack Kelly.
https://www.goodreads.com/book/show/6560617-gunpowder

**As measured in those days, with a hole in the barrel which allowed the pressure to deform a lead or copper ball.

 

[Jim Watson]

They found, for example, that a light steel cap would not affect pressure at all, since the bullet could easily pierce the sheet metal.

Which as I recall, they concluded was because it was outside the barrel.

 

[CapnMac]

"Double shotting" naval cannons was possible as the muzzle-loaders had considerable "windage" (the shot were "underbore" or the barrels were "overbore"--take your pick).
Typically this halved the range but doubled the potential damage. An acceptable trade if closed to less than 400 yards' range.

If really close, under a hundred yards, loading cannister over double shot was middling common, too. Not quite "triple shot" but getting close.
You generally could not double the powder, as, by that time, the powder chambers were running 1/2 bore by then,

 

[PapaG]

Muzzle loading rifles were sometimes loaded with two patched balls on top of the powder. I've done it. Poi was not bad out to fifty or so yards. Five or fewer inches spread. You must be sure that the balls are right down tight on top of each other or the top one becomes an obstruction.
In WHBSmiths book on the Civil War rifles there were instances of as many as 11 loads found in battlefield pickups. Obviously the first was a dud but the soldier just kept loading and snapping in the heat of battle.

 

[buck460XVR]

Unless the stuck bullet was at the very end of the barrel and did not get the benefit of getting up to speed, I can' see how the shot column would have different velocities. No real difference than those multiple projectile SD cartridges made for .45/.410 handguns. But then, I ain't no expert and don't plan on "shooting out" a stuck bullet.

 

[Riomouse911]

Unless the stuck bullet was at the very end of the barrel and did not get the benefit of getting up to speed, I can' see how the shot column would have different velocities. No real difference than those multiple projectile SD cartridges made for .45/.410 handguns. But then, I ain't no expert and don't plan on "shooting out" a stuck bullet.

I bought a beautiful 8 3/8” S&W Model 14-3 that had a very discreet bulge about 2 1/4” from the muzzle. No doubt the original owner was shooting powderpuff loads and stuck one before firing the next one. I wondered what was up with it when it had sub par accuracy with my go-to target loads. Once I ran a patch down the barrel I felt the patch slip when it hit the bulge .

Its been almost a year since I sent it to a gunsmith to be cut down to 5”, the covid issue still has me deep in a long line to get worked on.

CSI, NCIS, Chicago Fire, etc. are all fantasy shows that may, occasionally, have a plot line gleaned from a real event for an episode or two. Other than that rare tint of reality-based storylines, like James Bond movies and Danielle Steele novels these things are pure fiction.

Stay safe.

 

[Hal]

(Mods please move this if another section is more appropriate)

A question please for those more knowledgable than I. This question is was sparked by a NCIS episode.

If you have a squib load where where the first bullet is stuck in the barrel and then a second round (not a squib load) is fired which pushes both bullets out of the barrel do the bullets wind up having the same velocity or two different velocities. Supposedly the firearm in question was a 9mm semiautomatic.

I realize that this is much more of a theoretical question than an actual question, after all who is going to purposely make a gun have a bullet stuck in the barrel and then use a chronograph while firing another round, thereby risking destroying the gun, the chronograph and possibly injuring/killing the shooter. Not even sure a chronograph could measure two projectiles so close together.

Anyone with knowledge about this please respond. Thank you, NukemJim

This may actually have been based on fact.
TV and Hollywood both are filled with lots of fantasy - but - according to this https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6474521/

They may have borrowed from the truth.