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Survival Reloading: Part four
FINE TUNING LOADS
Once you are ready to find out how accurate your loads or reloads ) can be, we are now going deep into the woods requiring one more tool: the loaded round runout indicator with a 0.0001 dial indicator.
Back in the 1970's in California, Chet Brown developed the first called the Little Wiggler. He gets the credit for discovering the effects of runout on group sizes.
From memory the procedure is simple: mark the high point of your loaded round with a pen on the case head and load it at 12 O'clock in you chamber for purposes of consistency after you have segregated the runouts into groups.
For serious uses at long ranges segregate Pile #1 by runout 0.000" to 0.001"
Pile #2 0.001 0.003" varmint uses
Pile #3 0.003- 0.005" plinking
Pile #4 greater than 0.005" fire forming
How do you develop small groups?
LOAD DEVELOPMENT: Method #1
300wsm bolt only
A. verify all length and powder dimensions/ values
B. fill case with starting load of (51.0) normally accurate grains, long to touching lands. This is the highest pressure load length.
C. Measure velocity; if low, go up in 1/2grain increments until velocity is close to 2,800fps. If unable, go to D.
D. Check for pressure signs on primer and bolt
E. At desired velocity, shoot three shot group and measure (100 yds)
F. Shorten load by 0.005
Once you are ready to find out how accurate your loads or reloads ) can be, we are now going deep into the woods requiring one more tool: the loaded round runout indicator with a 0.0001 dial indicator.
Back in the 1970's in California, Chet Brown developed the first called the Little Wiggler. He gets the credit for discovering the effects of runout on group sizes.
From memory the procedure is simple: mark the high point of your loaded round with a pen on the case head and load it at 12 O'clock in you chamber for purposes of consistency after you have segregated the runouts into groups.
For serious uses at long ranges segregate Pile #1 by runout 0.000" to 0.001"
Pile #2 0.001 0.003" varmint uses
Pile #3 0.003- 0.005" plinking
Pile #4 greater than 0.005" fire forming
How do you develop small groups?
LOAD DEVELOPMENT: Method #1
300wsm bolt only
A. verify all length and powder dimensions/ values
B. fill case with starting load of (51.0) normally accurate grains, long to touching lands. This is the highest pressure load length.
C. Measure velocity; if low, go up in 1/2grain increments until velocity is close to 2,800fps. If unable, go to D.
D. Check for pressure signs on primer and bolt
E. At desired velocity, shoot three shot group and measure (100 yds)
F. Shorten load by 0.005
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