Complex sentence: Despite their enormous power the short low velocity slugs still suffered the penetration issues which plagued guns of this era, particularly for the toughest shot of all-defeating the bone mass for a frontal brain shot on an elephant.
Split into simpler sentences: Despite their enormous power the short low velocity slugs still suffered the penetration issues which plagued guns of this era. Particularly for the toughest shot of all, defeating the bone mass for a frontal brainshot on an elephant.