The paragraph above with the equation, it needs to be re though out and re stated.
I tried to follow it with my cartridge and bullet dimensions it just doesn’t make any sense as it written now
The paragraph above with the equation, it needs to be re though out and re stated.
I tried to follow it with my cartridge and bullet dimensions it just doesn’t make any sense as it written now
Perhaps an illustration will work better for you. This is for my particular bullet and load, but it works with any combination. The case mouth to wad measurement will be done with the depth mic on your calipers. It's simple, insert the wad, and use your compression die to compress the charge until the desired depth is achieved, so you can seat your bullets without air gap between the wad and bullet. If one desires, you can also measure your compression by pressing the wad down on top of the charge with a dowel rod without compressing the charge itself, and measuring the difference.
Thank You Tmanbuckhunter your further text explanation and photo of the math makes the concept perfectly clear to me now.
It turns out that I have been doing powder compression to approximately equal my bullet base to crimp point measurement. My case lengths 45 Colt vary ~7 thou I’ll trim soon after a couple more firings just to see if they‘ll stretch a bit, starting to believe they won’t.
Not enough pressure to push the case head back up against a bolt face, or frame and cause the brass to stretch. The brass flows somewhere on a low pressure straight wall case upon firing and it's usually backwards. Sizing increases the issue. Even bottle neck cases will shrink rather than stretch if pressures are low enough.
I've never tried light or low pressure black powder loads, rather I fill the case to the point of compression. (smile)
Thanks for the explanation,
Dave
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |