No, they're completely different. The Hawk can be a bit sticky in some rifles because they're dead soft and seal the bore completely. You really have to start low with them and work up. If the bore diameter is a bit tight to begin with, pressures can become excessive fast. Did you slug the bores in the .450 before you started? I worked up with them in one of my doubles yesterday due to a new lot of powder. No pressure issues and extremely accurate. Out of three consecutive pairs, the three rights went into .5" and two of the lefts went into the same hole at 50 yards.

Barrel damage from mono-metal bullets in double rifles has nothing to do with pressure.
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