Cartridge is from Ammo Manufacture: Underwood 140gr Lehigh Controlled Fracturing Hollow Point (100% solid copper)
Ballistics Information: 10mm Auto
Muzzle Velocity: 1550 fps
Muzzle Energy: 746 ft. lbs
Brass Make/Headstamp: Underwood - Brass
Bullet Make/Weight/Construction/Info; Length 0.6730"/Dia. 0.3910": 140gr CF
Actual weigh 139.8 grains Crimp Diameter 0.4000" *
HP Depth: 0.4200" / HP Cavity: 0.1730 tapered / HP Mouth 0.2375" (Three segments cut to 0.4045" to the first band)
C.O.A.L.: 1.2540"
Primer: Large Pistol Nickel color
Case: Diameter 0.4215" Crimp Diameter 0.4220" (Light Crimp)Length 0.9870"
Powder Description/Positive ID/Type/Charge Weight: LongShot 11.6 grains
*Base was smaller @ 0.3910" crimp area 0.4000"
(https://s20.postimg.cc/6odrgls3h/IMG_0087_zpsd219971f.jpg)
(https://s20.postimg.cc/e4d12enil/IMG_0088_zps9dbb7c52.jpg)
(https://s20.postimg.cc/9igwu29p9/IMG_0089_zps19d50561.jpg)
I had a hunch these weren't Power Pistol. They didn't have that sonic boom.
Read about the base section of these bullets being smaller than 0.4000" :o That would be less frictional surfaces, it would also lead me to believe they would be less accurate at long distance. ::)