Toymaker
05-15-2013, 12:41 PM
Hope this is the right room for this. Its about a Rigby, cap lock, .451 caliber, pure lead 525 grain bullet, my own lube mix, card wad, 45 grains Goex FFg. I've been using this load since 1998 in steel silhouette matches and it's been a tack driver. Suddenly it started hang firing and misfiring. Range tests also showed a keyhole problem. The load is on the razor's edge of ballistic stability, I know. But it worked great. Going back through my notes I find I put in a new nipple (recessed flash-hole) and bought more powder just before the problems started.
I replaced the nipple with a flat base flash-hole and stopped the hang fires and mis-fires. Maybe the powder was made with oak charcoal instead of willow, so I upped the charge 5 grains. Instead of 1 fouling shot it takes about 10 shots before it starts grouping. Where it would give me a 50 cent sized touching 5 shot group at 100 yards it now gives me a 3 inch group.
I'm thinking of going to FFFg powder but thought I'd put the situation out and see what others think may have for solutions.
BTW - I don't want to increase the charge too much. Been there, done that, got the bruises. At 65 grains FFg it's like holding the southern end of a north bound mule.
I replaced the nipple with a flat base flash-hole and stopped the hang fires and mis-fires. Maybe the powder was made with oak charcoal instead of willow, so I upped the charge 5 grains. Instead of 1 fouling shot it takes about 10 shots before it starts grouping. Where it would give me a 50 cent sized touching 5 shot group at 100 yards it now gives me a 3 inch group.
I'm thinking of going to FFFg powder but thought I'd put the situation out and see what others think may have for solutions.
BTW - I don't want to increase the charge too much. Been there, done that, got the bruises. At 65 grains FFg it's like holding the southern end of a north bound mule.