Swaged lead HBWC will behave a little differently from a cast lead HBWC. Swaged lead is very soft and too much velocity can cause the hollow skirt to separate from the core of the bullet. Cast lead is harder and will tolerate a higher velocity. I'd say 650-700 fps would be good for a swaged lead bullet, but it will take a little more pressure to get a cast HBWC's skirt to expand and seal the bore, so a cast HBWC at 700-800 fps should be good. Nevada Ed is right about the solid wadcutter bullets, which are usually cast lead. Those can be driven to even higher velocity, just like a cast semi-wadcutter or round nose bullet.

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