Powder adjustment bullet shape

[Revilo]

reloading manuals recommend minimum and maximum charges AND most of the bullets listed are boat tails. Question: if the manual recommended maximum 43 grains on a 120 grain boat tail, how much of an adjustment (and in which direction) would you allow for a 120 grain “flat base” bullet not listed in the manual? Assume similar bullet construction and materials.

 

[edwardware]

None, but always work up.

The change in pressure from BT to FB is a fraction of the effect of chamber and barrel variations. This is sufficiently addressed by simply starting low and working up.

 

[WelshShooter]

Check the powder manufacturers data too as there may be similar bullet profiles on there. I've never had issues using the same bullet weights but different profiles. As above, start from min and work your way up.