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**JohnKSa** · November 14, 2022, 06:02 PM

Mythbusters did a test with a crash test dummy. They set it up with an AR500 plate in its chest.

They shot it with a .50BMG at arm's length distance. The bullet did stop in the dummy. It went through the plate but stopped in the metal spine.

The dummy was not moved backwards by an appreciable amount.

Here's more on that test, including some screen captures from the test.

https://thefiringline.com/forums/sho...5&postcount=15

The problem is that there's all kinds of energy used up doing things other than moving the target. I've seen slow motion footage where a bullet impact on steel causes the steel to splash like water and/or the bullet to deform like a marshmallow. That's energy that's no longer available to push the target backwards because it was used to do something else.

Here's a post with a link to a guy with a ballistics vest getting shot with a .308 rifle at close range. He stands on one foot and the rifle still doesn't knock him down.

There's another link showing rifle testing using a live person wearing a bulletproof vest.

https://thefiringline.com/forums/sho...0&postcount=71

Even with the bullet stopping in the target, even when the bullet is from a .50BMG there's no significant push backwards.

Remember, momentum transfer requires inelastic collision. Once things start deforming appreciably there's no way to get an accurate picture of what's going on from simple momentum calculations.

November 14, 2022, 06:02 PM	#22
JohnKSa Staff Join Date: February 12, 2001 Location: DFW Area Posts: 24,973	Mythbusters did a test with a crash test dummy. They set it up with an AR500 plate in its chest. They shot it with a .50BMG at arm's length distance. The bullet did stop in the dummy. It went through the plate but stopped in the metal spine. The dummy was not moved backwards by an appreciable amount. Here's more on that test, including some screen captures from the test. https://thefiringline.com/forums/sho...5&postcount=15 The problem is that there's all kinds of energy used up doing things other than moving the target. I've seen slow motion footage where a bullet impact on steel causes the steel to splash like water and/or the bullet to deform like a marshmallow. That's energy that's no longer available to push the target backwards because it was used to do something else. Here's a post with a link to a guy with a ballistics vest getting shot with a .308 rifle at close range. He stands on one foot and the rifle still doesn't knock him down. There's another link showing rifle testing using a live person wearing a bulletproof vest. https://thefiringline.com/forums/sho...0&postcount=71 Even with the bullet stopping in the target, even when the bullet is from a .50BMG there's no significant push backwards. Remember, momentum transfer requires inelastic collision. Once things start deforming appreciably there's no way to get an accurate picture of what's going on from simple momentum calculations. __________________ Do you know about the TEXAS State Rifle Association?