Is measuring MOA at 100 yards useful for a long range target rifle? I say NOT

MikeinCalgary

MikeinCalgary

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I finally got around to doing some bullet seating depth tests, a year after doing my powder charge test, and decided to do a preliminary test at 100 yards (no wind) before trying this out at 300 yards. Below are the results, each is a five shot group at 100 yards, so I'll focus on a base to ogive length of 1.811 to 1.818 for the next round at 300.

It struck me that measuring MOA at 100 yards was a useless exercise since once you subtract out the bullet diameter there is not a lot to measure, and my bullet is 6mm so it's skinny to begin with. I know once I am at 300-400 this is more meaningful since the bullet diameter is not as significant a factor. I was also looking at some of the precision rifle classifieds on gunnutz and noticed that where MOA is mentioned many are taken at 100 yards and of course look very good. So the question I have for you precision guys and girls is, are we just fooling ourselves (or others) by taking these sorts of measurements at 100 yards for a long range rifle?

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When I was doing the same thing I loaded an extra two rounds to shoot at 100 yards to be sure I would be on paper (8.5x11) and then did everything else at 300, 500 & 750 meters. When groups are averaging 3.5cm at 300meters why even try so close?
 
Measuring with something other than a tape measure helps a lot.

A load accurate at 100y is not always accurate longer range.

Issue is getting 300-500y without wind variables is difficult. Also, many people don't have access to this distance.
 
Unless you are a 100 benchrest shooter, 100 yd groups don't mean much. If you are looking for loads for longer distance shooting, they need to be developed at longer distances. The shortest I test at is 300 and I prefer 500.

Here is a 525 yard group (308 -155 Sierra)

RAILGUN308AT525.jpg
 
Measuring at 100 meters is a good step, just as how someone might start at 10 meters, and then 25, then 50 and so forth. The only problem is stopping at 100, if you intend to shoot further than that.

After all your gun isn't going to get more accurate, but depending on how dialed in you are you might be feet upon feet off not only the bullseye but the entire target at 600m. You've got to work your way out there.
 
1) Ladder test at 500yds to establish nodes then (2) I do node load testing at 200yds to make sure the data jives, and (3) final tweaking at 400yds. If i go out to shoot groups for fun, i usually do 300 or 400yds.
When i got into this gig, 100 was the start, then 200, etc - as i got better (both guns, loads, and mostly shooter), i moved out farther and farther.
But definitely get more valuable info the farther out you go. Some wicked 100yd groups really suck at 300+ yds, but 300yd groups usually are pretty good at 100. Some bullets are stable immediately, some take some distance.
 
Results at 100 yard are perfectly valid if you intend to shoot 100 yards. Results at 100 yards are still a starting point regardless of the ultimate goal. Three shot groups at 300m and beyond are valid if you can find a match which features a three shot course of fire. That said, a poor three shot group at any distance won't get smaller with more shots so it makes sense to stop.
 
I agree 100 to get myself on paper. Then I move on out to 300 bypassing 200. At the same time at 300 I make sure my scope is tracking as it should. I then move on out in 100 yard jumps to 700 which is as far as I can shoot on the farm. At the same time I log come ups, wind, temp. and humidity. I do the logging a few different times in different weather conditions.
 
Ganderite said:
Unless you are a 100 benchrest shooter, 100 yd groups don't mean much. If you are looking for loads for longer distance shooting, they need to be developed at longer distances. The shortest I test at is 300 and I prefer 500.

Here is a 525 yard group (308 -155 Sierra)

RAILGUN308AT525.jpg
Click to expand...

Wow, you are so lucky you didn't hit that watch....lol

I do the same(300m) not much gained at 100m with load development. I try to develop at the same general distance I plan to shoot that recipe.

Plus I am amazed at what is great @400m isn't always as great at 100m.
 
I've stopped shooting groups at 100. Only group at 300 yards. The weird part, I'm about 3/4 moa at 100m, but 1/3-1/2 moa at 300y.
 
If its good enough at 500 or 1000 its going to be plenty good enough at 100. It doesn't necessarily work the other way around.

I don't know if the obsession with 100 yard groups is because many people only have 100 yard ranges to work with; or if people are frightened by reality and would rather believe in a comfortable fantasy/theory. It might be related to people who tend to think putting all their misses in the same place is more important than hitting the target. ;)
 
Like most others I don't bother at 100. I usually recommend that load development is done at 200 or 300 with 300 being better BUT be aware that at 300 the dreaded 'user error' may skew results.
 
100y is kinda useless for any benchrest guys. I was at our new range yesterday trying out my new .220, and a guy sat down with a .284 F-class rifle, brought out the rest and bags, shot one shot at one target and 3 at another. The first shot was dead center, the second 3-shot group looked like a slightly larger caliber was shot at the center. The group would have measured much less than a tenth of an inch! He then packed up and went to reload another 50 rounds, he just had to empty the extra 4 rounds he had.

For someone like myself, 100y works, 200y is better and probably good enough for load development. For someone who is competing, I doubt it.
 
Many shooters do not have convenient access to ranges longer than 100.
I'm currently working up loads for my .260. Testing at 300m. I'm watching the vertical dispersion, not bothering to compensate for wind.
 
I've shot 180 rounds tuning my load, the first time I shot at 100yards was after everything was finished.
 
Everyone has to start somewhere and 100yds is as good as any place really.

I think the next load I develop will be done with the chrony and that is about it. My theory is that if the SD is low (<10 FPS) the load will be consistent. Simplifying as I know other factors come into play but that is the general idea.

Maybe it will work and maybe it wont but it will be more scientific than my usual process.
 
Chronographs are really only useful for testing if your given powder is going to produce speeds that your happy with. Chrono'ed SD means nothing. Your targets will tell you everything you need.
 
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