First I would take MCMXI's posts to the bank and bet they would cash them. Thank you Sir. I say that as I am using his data here. Please help me with what I'm missing in psi -v- fps. I'm loading for a 6.5 cm and have been reviewing posts. In MCMXI's post r/t this thread he charts a psi of 58,985 rendering fps of 2,852 and a psi of 60,322 with fps of 2,870. This makes sense. I believe he is using Reloader 17. I have H 4350 and in there site they state a psi of 59,200 will render fps of only 2,660. MCMXI's data bracket the H4350 while both being higher fps. The difference, I believe, is significant at greater distance. Barrel length? Thoughts?
What am I missing?
- Thread starter CANNONMAN
- Start date
- Status
There is more to it than just pressure equals velocity.
Different powders have different burn characteristics. One powder may achieve a given pressure earlier and maintain that pressure for a longer period of time. Other powders may just spike in pressure.
A warm or hot test barrel will achieve a different velocity than a cold one.
Different bullets have different ballistic coefficients (BC) and will decelerate at different rates after leaving the barrel.
Different powders have different burn characteristics. One powder may achieve a given pressure earlier and maintain that pressure for a longer period of time. Other powders may just spike in pressure.
A warm or hot test barrel will achieve a different velocity than a cold one.
Different bullets have different ballistic coefficients (BC) and will decelerate at different rates after leaving the barrel.
- Status
