The Firing Line Forums - View Single Post - Anybody else heard of this "rule" of reloading?

taco · September 15, 2002, 01:03 AM

Many years ago (about 18 years ago) when I started getting interested in reloading I was “taken under the wings” of a very knowledgeable and experienced reloader. He used to let me come to his warehouse (he used to rent a small warehouse in the industrial area for his hobby) on weekends to learn the safety and basics of casting bullets and reloading. I spent months going there and learning until he passed away. During one of by visits there he told me that every “professional” reloader knows that for any give load of “factory pressure” (I think he meant “standard pressure”):

* Every 5% increase in powder charge will increase the velocity by 2 ½% and increase pressure by 10%.

* Every 5% decrease in powder charge will decrease the velocity by 2 ½% and decrease pressure by 10%

* Every 5% increase in internal capacity (by seating bullet further out) will decrease velocity by 2 ½% and decrease pressure by 10%.

* Every 5% decrease in internal capacity (by seating bullet deeper) will increase the velocity by 2 ½% and increase the pressure by 10%

I don’t know if this true or not but it made since to me at the time and I still use it as a guideline when reloading.

Anybody else ever heard of this?

September 15, 2002, 01:03 AM	#1
taco Senior Member Join Date: April 28, 2000 Location: USA Posts: 936	Anybody else heard of this "rule" of reloading? Many years ago (about 18 years ago) when I started getting interested in reloading I was “taken under the wings” of a very knowledgeable and experienced reloader. He used to let me come to his warehouse (he used to rent a small warehouse in the industrial area for his hobby) on weekends to learn the safety and basics of casting bullets and reloading. I spent months going there and learning until he passed away. During one of by visits there he told me that every “professional” reloader knows that for any give load of “factory pressure” (I think he meant “standard pressure”): * Every 5% increase in powder charge will increase the velocity by 2 ½% and increase pressure by 10%. * Every 5% decrease in powder charge will decrease the velocity by 2 ½% and decrease pressure by 10% * Every 5% increase in internal capacity (by seating bullet further out) will decrease velocity by 2 ½% and decrease pressure by 10%. * Every 5% decrease in internal capacity (by seating bullet deeper) will increase the velocity by 2 ½% and increase the pressure by 10% I don’t know if this true or not but it made since to me at the time and I still use it as a guideline when reloading. Anybody else ever heard of this?