If I had a Hammer
19 January 2025 07:56 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
dime_novel_heroAccording to my last outing with my lever gun, I was shooting 6.92 inches to the left at 100 yards. If I was going to not embarrass myself at match when I go to CQB/Brutality East (link) on Memorial Day, I was going to have to be able to adjust for that. The simplest way to do that is with what is called Kentucky Windage wherein, if you are shooting too far to the left, just aim that far to the right.
And while that is acceptable for a known range, all those ranges in between needs adjusting. Aiming 7 inches to the right may be not that much of a challenge on a known target size at 100 yards, that means aiming at a point 3.5 inches to the right when shooting at 50 yards. And if the target size is different, that becomes a more difficult adjustment.
Simple isn’t necessarily better. What IS a better way is to adjust the sights so that you don’t have to do any of that math on the fly.
How much, then, to move the sights?
That’s a trigonometry problem. And while I did pretty well in trig, that was almost half a century ago and the Rob at Britishmuzzloader’s (link) Figure of Merit calculator (link) will do that thing for me in one step.
Move the rear sight 0.03 inches to the right.
There are tools available for precisely moving a dovetailed sight. Tools that are expensive and tools that I do not have. Instead, I must resort to the precision tools of my distant ancestors. . . a hammer.
OK, not just a hammer but a hammer tapping on a brass flat-headed punch (so as not to damage the steel of the sight). The trick is knowing how much 3 hundredths of an inch is. Well, I have a metal ruler marked in 32dths of an inch and that’s about 3 hundredths of an inch so I moved the guide on the ruler 1/32”, taped it so that, when I moved the sight enough, it would close the gap and that should be about right.
Right?
I did the thing so I needed to test the results. Out to the range.
Conditions were overcast and cold; 25 degrees with a light snow. I set up my target at 50 yards rather than the 100 of the previous outing because I didn’t want to have to walk out all that way to check. Ten rounds and. . . . no change.
I gave a few taps with the hammer again (didn’t have a vice for the precision measure) and did some more shooting with no change.
Doing the math, there had been SOME change, but it was very small. The group was 3.17 inches to the left. That would be 6.34 inches at 100 yards, compared to the 6.92 inches it was previously. I found another calculator (link). Putting in the 6.92 offset at 100 yards (and a 15.8 sight radius, the distance from the front to the rear sight) confirmed the 0.03” adjustment I should have made. It also told me that I still needed a 0.028” adjustment to get it right.
My guess is that my kludged together measurement with the ruler simply didn’t work. When I thought I was moving the sight, I wasn’t.
Maybe I need to take it to a gunsmith who has the appropriate tool.
And speaking of appropriate tool. . . My previous calculations had been done with a spreadsheet. That necessitated physically measuring each bullet impact and manually entering that data. I have downloaded a pair of apps to my phone that can do that by dragging and tagging a phone image.
The first was and app called Range Buddy (link) that I found for free. It did what I needed it to do but I had a lot of frustration with it trying to use non-rotated images or not allowing me to use images I had rotated manually.
I was so frustrated that I downloaded and paid $8 for an application called Ballistic X (link). This is the app recommended by the Cabin Fever Challenge (link). I ran into a lot of frustration with that trying to figure out how to adjust the range. On top of that, there are a bunch of additional features locked behind a $10 a year paywall.
Sorry, you’ve already got my money once, you aren’t getting more out of me every year. Besides, I like the graphical output from Range Buddy better. The mental adaptation to having an image rotated 90 degrees isn’t that big a deal. And besides, once I get the sights adjusted I won’t need any sort of calculator other than the basics needed for scoring.
Or, in the case of Cowboy Action or CQB/Brutality, did the metal target go ding?
And while that is acceptable for a known range, all those ranges in between needs adjusting. Aiming 7 inches to the right may be not that much of a challenge on a known target size at 100 yards, that means aiming at a point 3.5 inches to the right when shooting at 50 yards. And if the target size is different, that becomes a more difficult adjustment.
Simple isn’t necessarily better. What IS a better way is to adjust the sights so that you don’t have to do any of that math on the fly.
How much, then, to move the sights?
That’s a trigonometry problem. And while I did pretty well in trig, that was almost half a century ago and the Rob at Britishmuzzloader’s (link) Figure of Merit calculator (link) will do that thing for me in one step.
Move the rear sight 0.03 inches to the right.
There are tools available for precisely moving a dovetailed sight. Tools that are expensive and tools that I do not have. Instead, I must resort to the precision tools of my distant ancestors. . . a hammer.
OK, not just a hammer but a hammer tapping on a brass flat-headed punch (so as not to damage the steel of the sight). The trick is knowing how much 3 hundredths of an inch is. Well, I have a metal ruler marked in 32dths of an inch and that’s about 3 hundredths of an inch so I moved the guide on the ruler 1/32”, taped it so that, when I moved the sight enough, it would close the gap and that should be about right.
Right?
I did the thing so I needed to test the results. Out to the range.
Conditions were overcast and cold; 25 degrees with a light snow. I set up my target at 50 yards rather than the 100 of the previous outing because I didn’t want to have to walk out all that way to check. Ten rounds and. . . . no change.
I gave a few taps with the hammer again (didn’t have a vice for the precision measure) and did some more shooting with no change.
Doing the math, there had been SOME change, but it was very small. The group was 3.17 inches to the left. That would be 6.34 inches at 100 yards, compared to the 6.92 inches it was previously. I found another calculator (link). Putting in the 6.92 offset at 100 yards (and a 15.8 sight radius, the distance from the front to the rear sight) confirmed the 0.03” adjustment I should have made. It also told me that I still needed a 0.028” adjustment to get it right.
My guess is that my kludged together measurement with the ruler simply didn’t work. When I thought I was moving the sight, I wasn’t.
Maybe I need to take it to a gunsmith who has the appropriate tool.
And speaking of appropriate tool. . . My previous calculations had been done with a spreadsheet. That necessitated physically measuring each bullet impact and manually entering that data. I have downloaded a pair of apps to my phone that can do that by dragging and tagging a phone image.
The first was and app called Range Buddy (link) that I found for free. It did what I needed it to do but I had a lot of frustration with it trying to use non-rotated images or not allowing me to use images I had rotated manually.
I was so frustrated that I downloaded and paid $8 for an application called Ballistic X (link). This is the app recommended by the Cabin Fever Challenge (link). I ran into a lot of frustration with that trying to figure out how to adjust the range. On top of that, there are a bunch of additional features locked behind a $10 a year paywall.
Sorry, you’ve already got my money once, you aren’t getting more out of me every year. Besides, I like the graphical output from Range Buddy better. The mental adaptation to having an image rotated 90 degrees isn’t that big a deal. And besides, once I get the sights adjusted I won’t need any sort of calculator other than the basics needed for scoring.
Or, in the case of Cowboy Action or CQB/Brutality, did the metal target go ding?
