The reason H110/W296 load data suggests not reducing maximum charges by more than 3% is that the propellant requires a minimum load density of 90% in order to burn correctly. I would imagine the reason the OP is getting extreme spread of 147 fps, etc. is because the load isn't maintaining the 90% minimum number. The maximum charge weight for this bullet is in the vicinity of 17.0 grains-depending on the source of the data. 97% of that (minimum charge) would be 16.5 grains. While I do not doubt that both Hodgdon & Hornady tested much lower charges and did not find them dangerous, the internal ballistics of those charges produced the results you recorded. This is not news. Further, just because these low charges appear to be safe (?), the performance is far from satisfactory.

I, for the life of me do not understand why the fact that H110/W296 is, has and always will be meant for maximum or very near maximum, full power loads does not sink in and stick. Possibly or probably the OP just wasn't familiar with the propellant. Having used both for 35+ years, I also cannot comprehend the very low starting charge weights in some published data. While the 10% reduction is the general rule of thumb, this propellant is the absolute exception to the rule. As a matter of fact, back in the days when H110 was a surplus powder and W296 was made by Olin, Winchester would only note a single charge weight for W296. They further stated that it was to be used EXACTLY as published with zero increase or reduction of charge weight. Low charge weight with H110/W296 pose a danger of a squib and not a Kaboom. I have never heard of an overcharge of H110/W296 causing a Kaboom but I have seen extremely sticky extraction and VERY flat primers.



Bruce