WWII Era 50 cal pen with armor piercing bullet

Some of you will recall my write up on a modified way to make 50 cal pens using 3D printed inserts and ball bullets

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Would a .50 Cal Sniper bullet penetrate a tank's armor (e.g. an

Could the .50 caliber machine gun of the M1 Abrams penetrate the

30-06 M2 AP Armor Piercing Penetration Tests - Pew Pew Tactical

High Caliber Craftsman - 50 Cal Armed Forces Bullet Pen - Made in USA

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30-06 M2 AP Armor Piercing Penetration Tests - Pew Pew Tactical

Did the .50 cals on American WWII aircraft have explosive rounds

In focus: the 50 cal heavy machine gun in Royal Navy service

50BMG M2 AP - Armor Piercing Ammunition Testing

Armor Piercing Caliber .30 M 2

Is there such thing as armor piercing shotgun shells? - Quora

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Can a 50 caliber armour-piercing round penetrate a Bradley IFV

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Sterling 7.62×39 123gr Steel case - Box of 20 - Shark Coast Tactical

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303 British ammo in Afghanistan