FRAMES per second... *facepalm*

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CLP

CLP

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Okay, so you have to put this in context. I was up until three last night, woke up at eight this morning, and had just started my coffee when I read this title from a GunsAmerica blog:
"MythBusters World Exclusive: Pistol Fired at 73,000 FPS"

What?! 73K feet per second?? I was sure I was going to be redirected to an advertisement because of such a preposterous claim, but was instead routed to this video instead. Doh!

Nevertheless, I always find slo-mo footage interesting. Enjoy!
 
I love the slo-mo shots as well but I find it hard to believe that a 1911 shot that 45ACP at 1200 feet per second as the video suggested. That's rather high for even +P rated ammo. However, it is a cool shot, if you pardon the expression
 
This should end a lot of arguments we've had here over the years about recoil affecting POA/POI with different bullet weights -- note the slide doesn't move until after the bullet is gone. This is not true for revolvers because they have two "recoils" one when the bullet leaves the cylinder to enter the barrel and the final one when the bullet exits the barrel -- the first recoil does effect the POA/POI with different bullets weights when shooting revolvers and the general trend is heavier bullets impact higher at close ranges before time of flight bullet drop overcomes it.

If you look carefully, frame-by-frame, you can see the slide first starts to move slightly when the gas blowby first starts exiting the barrel as Newton's laws require. Also its surprising how much blows past the primer at the rear.

I which they had shown the entire ejection and feeding cycle.

The white box on the table appears to say Remington 9mm Luger, although its hard to really make it out, so if its a 5" barrel 9mm 1911, 1200 fps is not totally our of line.
 
1 million frames per second.



The video around the 2 min mark is pretty impressive, if you have ever tried something similar.
 
wally said:
This should end a lot of arguments we've had here over the years about recoil affecting POA/POI with different bullet weights -- note the slide doesn't move until after the bullet is gone. This is not true for revolvers because they have two "recoils" one when the bullet leaves the cylinder to enter the barrel and the final one when the bullet exits the barrel -- the first recoil does effect the POA/POI with different bullets weights when shooting revolvers and the general trend is heavier bullets impact higher at close ranges before time of flight bullet drop overcomes it.

If you look carefully, frame-by-frame, you can see the slide first starts to move slightly when the gas blowby first starts exiting the barrel as Newton's laws require. Also its surprising how much blows past the primer at the rear.

I which they had shown the entire ejection and feeding cycle.

The white box on the table appears to say Remington 9mm Luger, although its hard to really make it out, so if its a 5" barrel 9mm 1911, 1200 fps is not totally our of line.
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I would guess that's not primer blow by but gas leaking past the brass before it seals the chamber.
 
I would guess that's not primer blow by but gas leaking past the brass before it seals the chamber.
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I'd bet you are correct.

Than Werner Mehl video is a work of art!
 
wally said:
This should end a lot of arguments we've had here over the years about recoil affecting POA/POI with different bullet weights -- note the slide doesn't move until after the bullet is gone.
Click to expand...
It moves when the bullet is still in the bore. It is only a few MMs so it is hard to see in a video - especially when none of the videos begin before ignition.

You can see the amount of movement in this picture by looking at the lower barrel lug and cross pin:
33o5ms5.jpg

This photo shows the bullet emerging from the barrel. Since this S&W has a guide rod it is easy to see just how much the slide has moved.
14.jpg


Conservation of movement and energy doesn't take pauses. The slide recoils immediately in equal and opposite reaction to bullet movement.

If recoil operated pistols work as you're suggesting, squibs wouldn't cause the slide to cycle. But they can and do.

As far as POI goes, are you saying you can see a fraction of a degree of muzzle rise? You can't. Only 0.2° of muzzle rise is a 3" change in POI at 25 yards.
 
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Similar to FTF. Is it fail to fire or fail to feed?

Slow motion photography really shows us the subtle things that happen is a short amount of time, that we generally never see otherwise.
 
I remember that episode it was initially titied on how fast a magazine change could be done. As I recall when I watched it the biggest "error" I saw was that when either Adam or Jamie dropped the mag and inserted a fresh mag they sling shotted the slide rather than using the slide release. They had a pro shooter do the same drill and as he reloaded he used the slide release to chamber the round.
 
larryh1108 said:
I love the slo-mo shots as well but I find it hard to believe that a 1911 shot that 45ACP at 1200 feet per second as the video suggested. That's rather high for even +P rated ammo. However, it is a cool shot, if you pardon the expression
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Just did a quick search and found a Corbon 165 grain that's advertised at 1,225. IF they got 1,200 FPS they'd have to use a very light bullet for a .45 ACP.
 
...note the slide doesn't move until after the bullet is gone.
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The slide/barrel definitely start moving while the bullet is still in the bore. RX-79G's post contains video links which prove that the bullet is still in the bore when the slide starts moving.

Based on the laws of physics, as soon as the bullet begins to move, so does the slide.
 
jmorris said:
1 million frames per second.



The video around the 2 min mark is pretty impressive, if you have ever tried something similar.
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Yeah - I can't imagine trying to hit a moving bullet with another projectile. I wonder how they did it?

I notice that the bullet, though deformed, did not seem to deviate visibly from its original trajectory.
 
They were taking about the camera speed
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LoL, pretty sure no one thought "fps" was feet per second, 1,000,000 feet per second would give some pretty impressive energy numbers though.

Rosco was talking about 2 minutes into the 1 million frames per second video where they are impacting bullets in flight from the side with other projectiles.
 
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