As stated earlier 165g. or 180g. only refers to the weight of the projectile. As for powder weight their is no direct relation. A 165g. bullet by the same manufacture may use a completely different powder than thier 180g. load. Also as stated earlier they load to certian pressure. Also for example not all 180g. 30-06 loads will be loaded to the same pressures. This can vary between manufacturers or different loads from the same manufacturers. For each round there is an excepted max. pressure (determined to be safe in all good conditioned guns that shoot that round) but some rounds are loaded to lower pressures. Also some are loaded to higher pressures and are called +P.

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