Lemonaid Wrote:I am very appreciative of the well thought out responses. Thanks! My thinking is that the velocity measurement is a better indicator of danger than the strict published "book" grain amounts, taking into account danger signals from the brass and the firearm.
If my conclusion is in error, please elaborate on how/what/why it is so.
I am trying very hard not to blow my face off!
Lemonaid,
As a follow on to what I said above., your reply generated some more thoughts.
One, if you start low (using the minimum starting load published, or a Max load minus 10%) and work up in .3 grain increments (for cases under 60 grains of powder capacity; .5 grains for cases over 60 grains) it's very hard to blow your face off, ever.
Two, never, ever, use somebody's pet loads as starting point. Always work up from below.
Three, where starting loads differ always choose to start at the lower one. Where MAX loads differ, always choose to work up to the higher one. Unless you see obvious pressure signs, then stop.
Fourth, using velocity as a pressure guide is OK, but also not always reliable or infallible. Your chamber, and barrel your length are critical in making or not making a particular velocity threshold.
Fifth, SAAMI Max pressures are often based on the original rifle a round was offered in rather than on the best, and strongest current rifle now available.
For example:
30-06 Max Pressure 60k PSI
270 Winchester Max Pressure 65K PSI
The two cases are structurally identical. But the 30-06 Max's were based on weak 03 Springfield's and Winchester Model 95's. A modern 30-06 (a Rem 700 for example) can take as much pressure as a 270 Win (in a Rem 700) can.
A similar relationship exists with the 6.5 Grendel. A bolt action like the Howa Mini can take more pressure (and deliver more velocity) than an AR 15 can, but SAAMI Max is based on an AR15's strength not that of the Howa. How much more?? I don't know, but certainly more.
Again, IMHO and YMMV