44 Special +P data and report

[44MAG#1]

What continues to drive the bullet is the expanding gas itself not the pressure being generated."

Does the gas expand at a rate no faster than the bullet accelerates and makes room for it or does the expanding gases expand at a faster rate than the bullet accelerates which would infringe on its room for expansion?
If it expands faster than the bullet accelerates making room for it then pressure would be generated would it not? Correct or not correct?

The reason that doesn't affect the velocity is that pressure does not drive the bullet all the way out of the barrel."
If pressure doesnt drive the bullet does the bullet only move down the barrel by inertia once it gets booted in the rear? Can muzzle pressure not be measured? If it can't be measured than no pressure exists. If it can pressure exists.
I am just wondering. Could a small paper tube be placed on the muzzle of the gun and when the bullet exists if there are is no
pressure then the paper tube will be unharmed since there would be no pressure or would it be blown outward and destroyed by the pressure and gasses or would maybe the bullet moving so fast that the tube would be sucked in on itself or would the recoiling of the gun bending the tube of paper be the only damage. Correct or incorrect?
I am wondering.
I am a wondering machine.

[Bazoo]

It was I who messaged Larry about the pressure descrepencies. I believe I can answer your questions though I'm not a ballistician.

What continues to drive the bullet is the expanding gas itself not the pressure being generated."

Does the gas expand at a rate no faster than the bullet accelerates and makes room for it or does the expanding gases expand at a faster rate than the bullet accelerates which would infringe on its room for expansion?
If it expands faster than the bullet accelerates making room for it then pressure would be generated would it not? Correct or not correct?. The gas' expansion rate depends on the powder used mostly. Some have a rather constant rate of expansion while others expand at a progressive rate until consumed. The gas pushes the bullet at increasing speeds until the volume of gas no longer generates the pressures required to overcome the friction of the barrel.

The reason that doesn't affect the velocity is that pressure does not drive the bullet all the way out of the barrel.
If pressure doesnt drive the bullet does the bullet only move down the barrel by inertia once it gets booted in the rear? The expanding gas pushes the bullet most of the way out of the barrel. There is no way for the bullet to gain velocity once the gas stops pushing it. That is pressure, but it takes a much less amount of pressure to keep the bullet moving than it does to make it begin moving and accelerate it. If the barrel is long enough the expanding gas loses enough of it's force that the bullet will slow in the barrel.

Can muzzle pressure not be measured? If it can't be measured than no pressure exists. If it can pressure exists. The peak pressure is from a combination of factors, the primer concussion, the initial powder burning, and probably of primary influence, the bullet jamming into the lands of the rifling. Once that drops, the pressure itself no longer is driving the bullet as the pressure wouldn't be able to overcome the friction of the bore. Evidenced by firing a primer alone, or a primer and a very small charge of powder. In either instance the pressure drives the bullet into the bore but it stops dead in it's tracks. There is still some pressure at the muzzle but it's not enough to drive the bullet. (How much I don't know as I don't have pressure testing equipment). The expanding gas alone drives the bullet most of the way, even though some pressure is present most of the way.
I am just wondering. Could a small paper tube be placed on the muzzle of the gun and when the bullet exists if there are is no
pressure then the paper tube will be unharmed since there would be no pressure or would it be blown outward and destroyed by the pressure and gasses or would maybe the bullet moving so fast that the tube would be sucked in on itself or would the recoiling of the gun bending the tube of paper be the only damage. Correct or incorrect? A paper tube would not be destroyed by the expanding gas but rather moved. I doubt there would be enough gas or pressure to destroy it. It would also be disrupted by the pressure bow in the air caused by the bullet itself. You can see close to peak pressure vs gas expansion in a revolver, by placing a sheet of paper over the barrel cylinder gap and firing vs a piece of paper around the muzzle and firing.
I am wondering.
I am a wondering machine.

[ddixie884]

If you don't think there is still gas pressure at the muzzle, shoot a hot load in high grass. a .44 Magnum will leave a triangle of flattened grass. You can also hold a sheet of paper in front of the barrel and shoot a hole through it. I believe it will cause more than a .43 hole in it.

[rking22]

I think quick load outputs muzzle pressure. I suspect it to be at least 5000psi. I may tape a tolit paper cardboard tube to my 44special and do an experiment. Haven’t blown anything up since, well Saturday
I can say for certainty that the barrel cyl gap on a RSBH 44 mag will cut bluejean denim and bruise a leg! Even when the leather pad was where it was supposed to be, it was a notable impact! That was a book max load of 2400 and a cast 250 gr, but a 22 will shred a sandbag in short order.

[44MAG#1]

Really it doesn't matter whether there is negative, zero or positive muzzle pressure. Everyone is going to believe what they want to believe and will search until they find someone to back up what they believe regardless if the person they choose knows what they are talking about or not. Most want confirmation on what they believe regardless if it is wrong, partially wrong and right or right. That is human nature.
As long as a load is safe and the bullet goes to the target with the desired results is what matters. The minutiae is not really worth it.

[onelight]

How do you separate expanding gas in a tube plugged with a bullet from pressure , that is the point of burning powder , the longer the tube the more powder you can burn and you can use slower burning fuel to keep more pressure on the bullet longer and you can vent some of that pressure off to cycle an action or even control recoil , what am I missing ? Won't be the first time my common sense was flawed.

[Larry Gibson]

"Does the gas expand at a rate no faster than the bullet accelerates and makes room for it or does the expanding gases expand at a faster rate than the bullet accelerates which would infringe on its room for expansion?"

44Mag#1 essentially answered the first part of his question with the second part of his question (answer in bold). The expanding gas accelerates (expands) at a faster rate than the bullet....that is where the pressure on the bullet to move faster (accelerate) comes from.

As to muzzle exit pressure; it is the exit pressure and velocity of the gas that creates the muzzle blast. If the bullet exits the muzzle then there will be "muzzle blast" from the pressure of the powder behind the bullet. with very low end "cat's sneeze" loads sometimes not much but it's still there.

[ddixie884]

That is what I think too...........

[rking22]

Well, I remembered to blowup the paper roll today. Plenty of gas left at the muzzle to shreds the tube. Turned everything in front of the muzzle to stuff too fine to find. This gas and the pressure it creates is why muzzle brakes work, and are loud! And why suppressors work.
Before and after pics, Skeeter load in 5 inch gp100

[onelight]

I know that the gas escaping magna port style vents will seriously damage a hand if the gun is gripped over the ports and require multiple surgeries to fix . This happened to LE friend at the insistence of a defective trainer in a weapon retention course.
The gas generated by the powder charge can't go faster than the bullet allows it until it has away around the bullet or another path of exit. There is a reason a contact wound is much worse. It would be interesting to see a slow motion video of a contact wound on a gel block compared to that same load at a few feet.
We also talk all the time about flame cutting on undersized bullets another example of the same thing.

[44MAG#1]

I think you have proven what most of us have known for ages. New ideas pop up from time to time. Sometimes old knowledge is still good. Nothing wrong with that. Good job.

"Well, I remembered to blowup the paper roll today. Plenty of gas left at the muzzle to shreds the tube. Turned everything in front of the muzzle to stuff too fine to find. This gas and the pressure it creates is why muzzle brakes work, and are loud! And why suppressors work.
Before and after pics, Skeeter load in 5 inch gp100"

[rking22]

I know it’s no surprise to most, but came up and sounded like a fun “looky here”. With all the none sense out there on the web, it might prove informative to someone doing a search, down the road. Besides, I had the roll ....
Having my hand over a magnaport when fired gives me the willies, hope the “trainer” was duly educated and removed from that role!

[ddixie884]

Thanx for posting that rking22. It is very enlightening. I wish I had been there to see the confetti..............

[black mamba]

Four decades ago I worked at a gun store where we had a bullet trap in the back room, facing the doorway, so we could stand out in the store and shoot into the trap from about 10 yards away. On the left hand wall were the long gun cabinets, with nice, heavy sliding glass doors. We had done this many times, but not with a powerful handgun. I fired a round of factory 220 grain 41 mag hunting ammo through a six inch model 57 and . . . CRASH!! The glass door exploded! The handgun was about 2 feet away from the glass when fired, so we assumed it was the blast from the barrel-cylinder gap that popped it. Quite a shocker.