As I concluded in my aforementioned thread AA#9 Squibs in 45 Colt cases I believe other factors can exacerbate this erratic ignition problem, with AA#9 in revolvers, making it somewhat "circumstance specific" as with:
- loose throats: low/no initial resistance on the projectile. My Ruger had .454-.455" throats using .452" bullets.
- long bullet jump to the throats: basically the same as a loose throats situation even if you have tight throats once the bullet gets to them. I was shooting 45 Colt (+P)s in 454 Casull chambers.
- large barrel-cylinder gap: add this to the two above & you have another element reducing pressure, potentially causing erratic ignition, ending with the bullet stuck in the forcing cone.
- load position sensitivity: in a long case, with a less than ideal amount of powder to fill it, most of the powder may be sitting against the base of the bullet with an air gap before the primer induced by a barrel nose down condition before firing.
11.2grs of AA#9 only takes up 42% of an empty .357 case. The 140gr XTP seated to .310" deep will use up almost another 30% more giving you only a case fill of 71.9%.
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I think it would be foolish to shoot the remaining loaded rounds knowing now what others have already pointed out & not expect to have more squibs which could be potentially damaging & dangerous.
.
- loose throats: low/no initial resistance on the projectile. My Ruger had .454-.455" throats using .452" bullets.
- long bullet jump to the throats: basically the same as a loose throats situation even if you have tight throats once the bullet gets to them. I was shooting 45 Colt (+P)s in 454 Casull chambers.
- large barrel-cylinder gap: add this to the two above & you have another element reducing pressure, potentially causing erratic ignition, ending with the bullet stuck in the forcing cone.
- load position sensitivity: in a long case, with a less than ideal amount of powder to fill it, most of the powder may be sitting against the base of the bullet with an air gap before the primer induced by a barrel nose down condition before firing.
11.2grs of AA#9 only takes up 42% of an empty .357 case. The 140gr XTP seated to .310" deep will use up almost another 30% more giving you only a case fill of 71.9%.
.
I think it would be foolish to shoot the remaining loaded rounds knowing now what others have already pointed out & not expect to have more squibs which could be potentially damaging & dangerous.
.
