I did a non scientific test on 8mm bullet's years ago, you can see they expand just fine at 8x57 velocities. Even some of the heavy weights like 220 sierra game kings did well.
Bullets were shot in a stack of 2x8" pine wood stack about 2ft in length
Bullet: 195Gr Hornady Interlock SP
Retained: 160.6
Retention: 82%
Comments: 3/4 throught the stack
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Bullet: 200gr Speer Hot-cor sp
Retained: 177.5
Retention: 89%
Comments: 3/4 through the stack
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Bullet: 220gr Serria GMK
Retained: 186.9
Retention: 85%
Comments: Great looking mushroom, 3/4 through the stack
[Linked Image]
