joeb33050
03-13-2008, 08:09 AM
POWDER POSITION SENSITIVITY TESTING
Does the position of the powder in the cartridge case affect muzzle velocity, (MV); does powder position affect the standard deviation, (STDEV) of MV; and does that position affect accuracy?
Powder is moved to the FRONT of the cartridge case by holding the rifle at ~ a 45 degree angle and slapping the side three times, then putting it carefully on the rest.
Powder is positioned LEVEL in the case by putting the rifle on the rest and slapping the side ten times.
Powder is positioned to the REAR of the case by pushing a wad down on the powder.
I recommend cotton but use Dacron wads. Use as small a wad as works. I use a teased wad about dime to penny size, and push it on top of the powder with a pencil.
These loads, 15 of each last time out, are shot at 100 yards over my PACT chronograph.
I'll record all results on an EXCEL workbook called "POWDER POSITION SENSITIVITY" and a WORD summary, this is it, called " POWDER POSITION SENSITIVITY TESTING". (See the EXCEL workbook for all the information about the loads and results.)
These two files will be on http://sports.groups.yahoo.com/group/CB-BOOK/
in FILES,in ERRATA
3/12/08, 30/30, 14.5 IMR4227, WLP
Level Front Rear
1347 1353 1435
3/12/08, 30/30, 14.5 IMR4227, 2-1/2
Level Front Rear
1357 1357 1434
2/27/08, 45-70, 22 SR4759
Level Front Rear
1065 1310
2/27/08, 45-70, 14 Unique
Level Front Rear
1195 1240
2/20/08, 30/30, 10 Unique
Level Front Rear
1519 1502 1498
2/20/08, 30/30, 8.5 Unique
Level Front Rear
1365 1346 1378
2/6/08, 30/30, 7 Unique
Level Front Rear
1214 1195 1185
JOE B.
Does the position of the powder in the cartridge case affect muzzle velocity, (MV); does powder position affect the standard deviation, (STDEV) of MV; and does that position affect accuracy?
Powder is moved to the FRONT of the cartridge case by holding the rifle at ~ a 45 degree angle and slapping the side three times, then putting it carefully on the rest.
Powder is positioned LEVEL in the case by putting the rifle on the rest and slapping the side ten times.
Powder is positioned to the REAR of the case by pushing a wad down on the powder.
I recommend cotton but use Dacron wads. Use as small a wad as works. I use a teased wad about dime to penny size, and push it on top of the powder with a pencil.
These loads, 15 of each last time out, are shot at 100 yards over my PACT chronograph.
I'll record all results on an EXCEL workbook called "POWDER POSITION SENSITIVITY" and a WORD summary, this is it, called " POWDER POSITION SENSITIVITY TESTING". (See the EXCEL workbook for all the information about the loads and results.)
These two files will be on http://sports.groups.yahoo.com/group/CB-BOOK/
in FILES,in ERRATA
3/12/08, 30/30, 14.5 IMR4227, WLP
Level Front Rear
1347 1353 1435
3/12/08, 30/30, 14.5 IMR4227, 2-1/2
Level Front Rear
1357 1357 1434
2/27/08, 45-70, 22 SR4759
Level Front Rear
1065 1310
2/27/08, 45-70, 14 Unique
Level Front Rear
1195 1240
2/20/08, 30/30, 10 Unique
Level Front Rear
1519 1502 1498
2/20/08, 30/30, 8.5 Unique
Level Front Rear
1365 1346 1378
2/6/08, 30/30, 7 Unique
Level Front Rear
1214 1195 1185
JOE B.