SSS thing is it takes very little "off" to strike low in front of the target. Trajectory is so high at distance with our cast bullet rifles very small error on a paper target low at 100 yards will show up as a strike on dirt quite a bit in front of the target at 500. 

Ever notice how often a inexperienced spotter will call a low miss, throwing dirt up between the rams legs when you know you missed high over his back.  Lack of depth perception with a single eyepiece scope and distance back to the berm makes it look like low miss even when it passed the target high. Same effect for low misses, they hit way in front.

Same thing with long range game shooting using high trajectory rifles. Not effective due to the extreme trajectory causing wild high or low shots when the distance is not accurately estimated. And only takes a few yards to make a large difference in strike.  Quigley read the wind he should have paid attention to the distance.

It's likely more geometry than ignition, If the cartridge sounds right when it goes off it's probably right

Boats

Put 100rds+ through the rifle since it has been back together. Not a single misfire or light hit. With the tip from Dan Theodore that bottleneck cases (all of them when using cast bullets - will be annealing my 25-20 cases next) need to have the case mouth annealed for best accuracy, the load has gone from averaging ~1.5moa at 300yd to <1moa. Terrific results. Thank you C. Sharps for the terrific service and DanT for the info.

Been reading Nancy Tompkins excellent book, "Prone and Long Range Rifle Shooting" as am also shooting F-Class when it does not interfere with my single-shot rifle shooting. In the reloading section she addresses light primer hits and the poor results from same. In discussions with some very good F-Class shooters I mentioned same and they are all in agreement. One must have a good, consistent strong hit on the primer to get good, consistent results. Now that I've got that, its all up to me.

Those Anal fellows are regularly shooting groups in the 1's &'2's DW and we can learn from some of what they do. There is no reason that I know of that would keep us from doing the same.