Too many questions, and not much shooting looking for answers, so back in October 2013 I borrowed a rifle and did some shooting, finishing up on 26 January 2014. Technical details will follow in the next post.
First off, the rifle was a rather plain original Dickert (it reminds me of Kindig's #19). It was re-converted and restored by an overly-enthusiastic "gunsmith" in 1976. I had permission to shoot it, as long as I made no permanent changes other than to modify the touchhole liner and drill out the touch hole as needed to allow firing. The bore would not pass a .490" round ball.
I used two lots of powder, that I'd had on hand for 20+ years but never fired in a rifle, so they were unknown quantities. I settled on balls cast in an original mould marked only "44." The lead was scrounged from the backstop at a local range. I made a trip to the local purveyor of assorted fabrics (i.e., Goodwill) and purchased some linen (old table runner) of what I thought was probably an appropriate thickness, based on how it felt "in hand." Lube was neatsfoot oil, mostly because I frequently use that as a lube.
Initial load testing was done from a supported offhand position (I rested my left forearm on a fencepost). Beginning with the first lot of powder, I shot ten-shot groups at 50 yards, increasing the powder change 10 grains each time. Balls were placed on a strip of lubed patching, seated flush with the muzzle using the handle of my knife, then the patch was cut and the ball seated home using a loading rod I had on hand rather than the rod that accompanied the rifle. (This is pretty much my usual loading procedure.) Limited testing was done with pre-cut square patches and pre-cut round patches, but no difference in group size or POI was noted.
After watching groups shrink in size then begin opening up as the charge was increased, I returned to the charge that gave the smallest group and made a fixed charger. I then shot that load at 100 yards, where I found that when using a center hold on a 6" paper plate, about 8 of 10 shots would hit the lower half of the plate (the other two were usually right below the lower edge of the plate). Group sizes were typically about 6-7". Using a second lot of powder, I worked up a load that hit to the same point of impact at 100 yards, and again made a fixed charger for that load. (Group sizes with the second load were about the same as the first, but I didn't shoot enough groups to really be able to say for certain if one was better than the other. The charges were certainly different.)
From there I began testing. Ranges were 200 yards (supported offhand), 200 yards (prone), 300 yards prone, and 400 yards prone. The targets used were copies of the IPSC silhouette, measuring 30" tall (including the "head"), 18" wide, with a "head" measuring about 6" square. I put a white watch cap on the head to provide an aiming point similar to a powdered wig (and because I never liked that hat anyhow). A shot was fired, then the barrel cleaned with tow on a worm, the bore dried, and the barrel allowed to cool before reloading and taking another shot. On each day I shot, five shots were fired at each range, repeating a total of four days (total of 20 shots at each range). The series was then repeated with the second load.
In scoring the targets, I counted any hit on the silhouette as a "hit."
Load #1 results:
200 yard supported offhand: 15 hits
200 yard prone: 16 hits
300 yard prone: 11 hits
400 yard prone: 3 hits
Load #2 results:
200 yard supported offhand: 16 hits
200 yard prone: 19 hits
300 yard prone: 9 hits
400 yard prone: 1 hits
I only hit that dang hat twice.
Conclusions:
After the tests, I spent a couple of afternoons shooting at targets a friend had placed at random distances from my shooting position, and from known distances at targets placed in front of an old (soon to be torn down) barn so I could see the POI of misses in the same plane as the target. It was clear that out to 300 yards, the biggest obstacle to achieving hits was not range estimation but reading the wind. Practice had made me familiar with how the target would look in relation to my front sight at various ranges; at unknown ranges (if I read the wind correctly) I averaged about a 60% hit ratio to 200 yards, and about 25% from 200-300 yards. When shooting at the target in front of the old barn, I could see my shots strung out by the wind, often several feet or more, even at 200 yards.
While I am certain reading the wind was of even greater importance at 400 yards, I suspect the shooter/rifle/load combination was a more-significant barrier. I was having to hold over too much for my eyes to be consistent.