If it's a slower burn rate, just add more powder to get back the lost velocity unless there are noticeable signs your pressure is too high. 22cm is a case thay can run so many burn rates from H4350/rl16 to H1000/rl26. And all the stuff in between. It's quite versatile in that sense. A top end load with H4350, will only be 50-75fps behind a top end load with N555, H1000 or Rl23. Rl26 is always velocity king, but in small bores it carbons up very quickly.