W.E.G.
Member
My understanding is that N140 is "single-base," and N540 is "double-base."
I read somewhere that double-base powders are expected to be more "temperature stable" than single-base powders. That is, they are affected less by changes in temperatures.
I just ran some comparisons in Quickload.
Quickload tells me that N140 generally runs at a higher pressure, at any given temperature, than N540. That is an important thing to know, but it is not what I want to know about here.
By comparison when accounting for propellant temperature, the pressure increase from FORTY degrees to NINETY-FIVE degrees is:
4,280 PSI for N540
4,694 PSI for N140
So, the single-base powder, N140, fluctuates more in pressure by a "whopping" 414 PSI. Now mind you we are talking about 414 PSI in a cartridge wit a SAAMI spec of 62,336 PSI. That would mean that the 414 PSI in question accounts for just half of one-percent of the total pressure we are working with.
Maybe this is more of a RANT, than a question, but I just don't see the big deal in the idea that the double-base powder is APPRECIABLY a better choice than the single-base powder.
I welcome your thoughts and comments.
I read somewhere that double-base powders are expected to be more "temperature stable" than single-base powders. That is, they are affected less by changes in temperatures.
I just ran some comparisons in Quickload.
Quickload tells me that N140 generally runs at a higher pressure, at any given temperature, than N540. That is an important thing to know, but it is not what I want to know about here.
By comparison when accounting for propellant temperature, the pressure increase from FORTY degrees to NINETY-FIVE degrees is:
4,280 PSI for N540
4,694 PSI for N140
So, the single-base powder, N140, fluctuates more in pressure by a "whopping" 414 PSI. Now mind you we are talking about 414 PSI in a cartridge wit a SAAMI spec of 62,336 PSI. That would mean that the 414 PSI in question accounts for just half of one-percent of the total pressure we are working with.
Maybe this is more of a RANT, than a question, but I just don't see the big deal in the idea that the double-base powder is APPRECIABLY a better choice than the single-base powder.
I welcome your thoughts and comments.