How Many Layers of Clothes Can Stop a Bullet? - Science Meets Practicality
On YouTube, Demolition Ranch conducted an experiment to test the effectiveness of t-shirts in stopping handgun bullets. He found that 100 t-shirts from a charity shop were sufficient to stop a 9 x 19 mm round. This experiment raises the question of how many layers would be needed to stop different types of bullets and how heavy such a setup would be.
Experiment with T-Shirts
Demolition Ranch stacked t-shirts from a charity shop on a dummy and fired a 9 x 19 mm handgun at it. Surprisingly, 100 t-shirts were able to stop the bullet. This led to further exploration of how many layers would be needed for other types of bullets like the AK-47.
The AK-47 bullet is narrower at 7.62 mm, and each layer would require 0.717 times more cotton compared to the 9 x 19 mm bullet. Due to its pointed shape, it could push fibres aside and slip between them, requiring approximately 1.5 times as many layers for an equivalent energy extraction.
Calculating the Energy Requirement
The amount of energy released by the bullet is significant. For a 9 x 19 mm round, the energy is around 350 ft-lbf, while the AK-47 has an estimated 1600 ft-lbf. Using the higher value for caution, we calculate that 686 layers of t-shirts would be needed to stop the AK-47 bullet. This figure aligns with the weight of a brown bear, suggesting a truly formidable setup.
Practical Considerations
These findings pose significant practical challenges. A t-tunic made from 686 layers of t-shirts would weigh approximately 686 pounds, equivalent to a brown bear. This implies that the average person would need to wear multiple layers of heavy clothing, such as denim, to provide similar protection.
According to another video, a Hornady 115 grain JHP 9mm round can penetrate through five layers of denim. This suggests that even a single layer of heavy clothing, like denim, could provide some protection, but it is not enough to stop the most powerful rounds.
Conclusion
The practicality of such a setup is questionable. While heavily layered clothing could potentially mitigate the impact of lower-powered rounds, it would be overly cumbersome and impractical for most real-world scenarios. The suitability of such measures depends heavily on the specific caliber and velocity of the ammunition being faced.
For those interested in practical solutions, investing in specialized bulletproof vests or advanced composite materials might be a more viable option, providing effective protection without the bulk and weight of multiple layers of clothing.