I have experienced the same thing....usually more pronounced in the supersonic loads but also with subbsonic....if shooting an AR let the rounds heat soak in the chamber adding 10 seconds to each firing interval (30 sec..40sec...50sec...)...this can give you some idea of how long you can leave a round in a warm chamber before it comes up in velocity....some of the tests I have done with H110 and Winchester 296 the velocity will come up 100fps in a small amount of time, especially supersonic AR loads...
kurtz
|