Why are bullets shot into a barrel of water for testing?

One of these specifications is a characteristic known as rifling, which refers to the spiral lands and grooves placed into the firearm's barrel to impart a spin on the bullet for accuracy. ... Examiners generally test fire into a water recovery tank to obtain comparison bullets for evaluation under the microscope.

an adaptation is a change or process by which an organism takes to be better suited for its environment. for example; migration is a behavioral adaptation, this is needed because birds are not built to last extremely cold climates. there are different adaptations because there are different species needing to adjust to different things, bears don't migrate; they hibernate.

weathering - colorado river carves land in arizona to form the grand canyon. cracks form in a sandstone wall surrounding a house. a marble statue near the science museum is changing color due to rainfall

erosion - after a rainstorm, soil and rock piees litter the roadways. the sand dunes in the sahara desert are changing shape.

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