spitballer
Member
Okay guys I've got a question that has been vexing me for some time, and I wonder if anyone can explain it satisfactorily (explaining anything satisfactorily on this website is a tall order and that's EXACTLY why I'm throwing this question out there). It has to do with powder speed and bullet weight and load data for the .223 Remington (and just to be clear I have NO beef with data publishers, in fact I'm grateful for access to load data for safety reasons, obviously). Okay the question goes like this:
Let's take the example of H4895 - there's a vary narrow window of 25 to 26 grains for a 55 grain bullet which, according to my reloading manual, indicates that the propellant is approaching borderline with regard to pressure. Yet FASTER propellants like BL(C)-2 don't share the same narrow window of usefulness - in fact BL(C)-2 can be packed with 27.5 grains with that same 55 grain pill!
What am I missing here? Does the BL(C)-2 simply handle pressure better than H4895? Or does H4895 produce more pressure because it's speed of expansion more closely matches the speed of the projectile, producing sustained pressure or something? I've always wondered about this, and why certain propellants are more forgiving than others when it comes to pressure (and anecdotal evidence indeed supports the load data, they're not just making this stuff up). Thanks in advance to anyone who can shed some light on this phenomenon. -TH
Let's take the example of H4895 - there's a vary narrow window of 25 to 26 grains for a 55 grain bullet which, according to my reloading manual, indicates that the propellant is approaching borderline with regard to pressure. Yet FASTER propellants like BL(C)-2 don't share the same narrow window of usefulness - in fact BL(C)-2 can be packed with 27.5 grains with that same 55 grain pill!
What am I missing here? Does the BL(C)-2 simply handle pressure better than H4895? Or does H4895 produce more pressure because it's speed of expansion more closely matches the speed of the projectile, producing sustained pressure or something? I've always wondered about this, and why certain propellants are more forgiving than others when it comes to pressure (and anecdotal evidence indeed supports the load data, they're not just making this stuff up). Thanks in advance to anyone who can shed some light on this phenomenon. -TH