pocket, and initially pulled out the Mil-Dot Master,
which looks very similar.)
I developed a methodology to check my zero at regular yardage intervals with regular checks of my 100 yard zero. I also included a subjective barrel temperature rating to note before each group. I figured that this would be a good thing to do monthly for a while, just to keep track of what the bullets actually do in different conditions. That way, I get all my nerdy testing done to satisfy my curiosity on one range trip, so the rest of the month I can focus on actually shooting from positions. I’ve been getting stuck in data collecting phase too much lately.
My first impressions of the FDAC were that it makes what can seem overly complicated about as simple as it should be. It’s just reading dope off a chart in a familiar way, rather than doing a scientific experiment every time a shot is fired. I was impressed at the ease of use. As I said before, I wish it looked more different than the Mil-Dot Master. I have a lead fishing weight hanging off my Mil-Dot Master and I still get them confused. I wish they had used a 10 mph full value wind rather than a 5 mph, because I think it makes the math just a little easier. I wonder how well it works to use a generic load and a generic scope height to come up with the number needed to get a hit.
-Temperature: 45 (degrees, not ACP)
-The snow has been melting. It was muddy. I had an interesting “shooting mat”
The objectives for this range day were to function test 2 Glocks, test my ability to hit relatively small targets at intermediate distance (200-450 yards in this case), practice reticle ranging, and begin testing of the Field Density Altitude Calculator (FDAC). The FDAC is going to be a separate article and I don’t know if I’m going to elaborate on the Glocks in the future or not. For now we’ll cover the shooting and the ranging.
I was able to get out of work a little early. That went something like this (imagine the deep “boss” voice from the 1940 Donald Duck cartoon, “The Riveter” [my voice sounds pretty much like Donald’s]):
“Have a big Super Bowl party do you?”
“No, I need to get to the range.”
“Just kidding, uh yeah, big new flatscreen and, um, chicken wings or something, and, um (four second pause, eyes looking up and to the right), a keg of Bud Light.”
“Oh, well that sounds fine, just fine. Sure, you can leave a little early.”
I had about an hour of daylight/dusk-light. That’s not very long to get in any meaningful shooting. That means I had to be quick, efficient, and still not get in very much shooting.
I made a worksheet to streamline my shooting and data management process. I was gathering data on my ability to gather and handle data. I guess that makes this shooting session meta-data-tional or something. Sounds relaxing, huh?
I’m particularly interested in how different methods of range estimation and ballistic data compare in both accuracy and speed, since both are important. I used several methods of range estimation and retrieval of trajectory data. I haven’t had time to go over the results yet to see which ones were most efficient, but I’ll try to unravel that as I go.
On a side note, I found a really cool use for that damned unconnected iPhone that I also use for a ballistic computer. I hooked a 3.5mm plug into my MSA Sordins and listed to music the entire time I shot. It was Muddy Waters, Howlin Wolf, SRV, and Freddie King, for those who keep track of such things. RF was right about listening to music while shooting, it keeps the mental processes working nicely. My only complaint is the tinny treble and lack of bass altogether in the Sordins. They also translate sounds poorly in terms of direction. Other than that, they are great.
I started by shooting a dot drill just to get myself dialed in. I had created a 20 round dot drill target. I initially called it “20 Bucks”, but the cost of ammo seems to be in flux, so I called it “$$$ Dot Drill”. It was a typical dot drill, a nice blend of misses, misses, bad misses, and hits. My cold bore, as I said, was 0.3 mils high, but nicely centered. I shot 3 more with the same settings to see what happened, then adjusted 0.2 down (my best guess from distance). The shots that I fired before adjusting down 0.2 mils were the top four. File that sight correction away in your memory for a bit. I had significantly less of the far right miss phenomenon. I think it was trigger finger related.
After that I got on with my shooting. The setup was steel set on the berm and paper targets set up approximately 5 yards in front of that. One shot on steel, call a hit or miss, then 3 on paper to see what the ballistic data yielded. I have been avoiding groups, but I’m looking for data, so I couldn’t really avoid these. I had 5 steel targets. There were circles, 5.25”, 6.25”, 6.5” (x2), and a rounded rectangle, 9” x 10.5”.
The target setup.
I was going to follow the paper target with 3 additional attempts on steel from other positions. I wasn’t getting spectacular results from prone so I skipped that step this time. I’ll try it again.
On each target I would start my stopwatch, make a visual estimate on the distance to target, record the time, use the rifle scope to take a reading on the target size in milliradians, note the time, use the Mil-Dot Master to calculate distance based on my mil reading, note the time, take a laser reading, and note the time.
After the distance was established I would attempt to recall the elevation correction from memory and note the elapsed time. Then I would use the iPhone to provide a correction, and note the time. Then I would use the FDAC and note the time. I’ll go into more detail on this when I write about the FDAC, but actually I did a pretty good job of going from memory. I was consistently within 0.1 mils of one of the other methods on every shot.
I was only able to take shots at three targets due to the falling sun. The first was at 338 yards. My visual estimate was 320 yards (approximately 5 seconds). I measured the 2.5” wide target board at 2.2 mils and used the Mil-Dot Master to get an estimate of 319 yards (total elapsed time of 2:40- I had to get set up and find things in my gear). Used the laser (47 seconds- it’s old and I had to get a calculator to divide the number of feet by 3). I missed the 5.5” steel. My paper target looked like this:
0.2 mils up and 0.1 up would have put all the shots in the black.
2.94” at 338 yards is approximately 0.83 MOA. My worst group of the day.
I learned that the engine vibrations make the reticle vibrate. It’s better to shut it off and deal with the wear of constant starting of the engine. Don’t ask questions.
I drove to the next shooting location (not a lot of daylight, remember?) and this time turned off the engine. My visual estimate was 390, again in about 5 seconds. My initial mil reticle measurement of the target board was 2.0 (1:36 elapsed) which gave me a Mil-Dot Master range estimate of ~340. I’m pretty familiar with the range, so I knew that couldn’t be right. I re-measured and came up with 1.8 mils and 380 yards (2:01 elapsed). The laser told me 387 (2:46). Did the data thing and got a hit. I didn’t hear it, so I assumed I missed until I saw this:
Here’s what it looked like on paper:
0.1 mils up would have centered this group nicely. 0.2 up would have still all been in the black.
2” at 387 yards, approximately 0.49 MOA. Smallest size group, but second best.
0.1 or 0.2 mils up would have corrected the elevation. Same for windage.
2.13” at 456 yards, approximately 0.45 MOA. I seem to shoot more precisely at a bit of distance.
I use this range a lot, so obviously my visual estimations were based on more than just a visual estimate alone. What is clear is that I need to work on the accuracy of my mil readings for range estimation. Next time I will try from 200-350 yards.
What I noticed by looking at the numbers at the end was that the visual estimation is pretty quick (of course!), but at the range I’m familiar with it would have been sufficiently accurate to get me a hit, assuming that my data and zero were both correct, which of course at least one of them was not. The mil reading took significantly longer than using the laser (also pretty obvious). It would be nice to try it with a rangefinder that a.) read in yards, saving me a division math problem, and b.) gave me a quicker reading.
One thing I’m curious about is the 0.2 mils down I put into my zero before I started. 0.2 mils up would have corrected all the impacts at the longer ranges I shot. Was it the zero correction that was faulty or that data that I inputted?
Thanks for reading about my Super Bowl party.