1000 yd Accuracy

100yd groups should be more or less round, and as small as reasonably possible.

For shooting iron sights with slings, if your ammo can reliably shoot 3/4" groups (5 to 10 shots) at 100 yards, this will usually be adequate.

For shooting with a scope and a rest, it can be helpful if your groups are closer to 1/2" at 100 yards.

Smaller groups never hurt of course (!), but as soon as you can achieve the above (or something reasonably close to it), you shouldn't be held back.

Another factor that does not show up in 100yd testing, is whether or not your bullet speeds are consistent from shot to shot. This usually does not matter at 100 yards, and quite often it also does not matter at 600 yards. But at 1000 yards, if the shots in your string vary by (say) 50fps from the slowest shot to the fastest shot, what tends to happen is that the slower bullets will land lower on the target than the faster bullets.

For iron sights shooting at 1000 yards, if the Extreme Spread (difference in speed from your fastest to slowest shot) in a 10-shot string is more than 50fps, you should do what you can to reduce this to be less than 50fps (if your chronograph shows you Standard Deviation, this is equivalent to an SD of about 16fps).

For shooting with a scope and a rest, it is useful to try to get your ES to 35fps or less (SD of 12 or less).
 
Is the bullet you are using going to make it to 1000 yds and still be stable? 100 yds is a starting point but 300-400 yd. groupings will tell you more how the bullet is working. What cal rifle and what bullet are you using? What speed are you getting at 100 and have you run it through a program to see what speed is remaining at 1000 yds.
What I think you may be asking is what is the group needed at 1000 yds to be competitive?
 
Just because your rifle shoots a group of a certain size at 100 yards doesn't necessarily mean it will be proportionately larger at 1000. A load that produces good 100 yard accuracy, might or might not impress you at 1000 and a load that's sub MOA at 1000 might suck at 100. All you can do is to work up a load that will potentially stay supersonic at 1000 and give it a try. A round group is indicative of everything being right, but it doesn't take much wind to string em out at long range. If you're shooting for your own amusement, staying on a 12" steel plate at 1000 is entertaining, but if you intend to shoot in competition, you'll have to work up a load that produces consistent half minute groups under ideal conditions and work on beating the gremlins of wind, mirage, light and stress that come with being a competitive shooter. Use every trick you can think of to make your ammo uniform and consistent. Do what you can to minimize your extreme spread and be sure your necks are concentric.
 
Many top level shooters will tell you that they deliver half-minute accuracy at 1000 yards. It is probably good for their self esteem and for their continued good performance as shooters to say this and to think this. When I have been a coach, spectator and scorekeeper, this is something I have almost never seen.

At the top level of national competition, the top slings-and-iron-sights shooters are usually firing shots into a 15" group at 1000 yards under no-wind conditions. In a 10-shot or 15-shot string the majority of their shots may well be inside a 10" group, but counting all shots (and that's what a group is!), I think that 1.5MOA (15") at 1000 yards is a fair measure of a top level shooter. In Canada our target has a 24" diameter 5-ring and a 12" diameter V-bull, so a top level shooter is capable of shooting a "clean" score at 1000 yards with a high V-count (say a score of 50-7V for a ten-shot string in calm or near calm conditions).

For F-Class shooting, which uses rests and scopes, the top level shooters are usually delivering no-wind 10- or 15-shot groups of 10" more or less. The Canadian F-Class target has a 12" diameter 5-ring and a 5" diameter V-bull. While clean scores in F-Class at 1000 yards are possible within these parameter, they are *much* more difficult and are in practice rarely seen. In "reasonably straightforward" wind conditions one might expect a 1000 yard F-Class match to be won with a score like 47-3V (i.e. 7 out of 10 shots were inside the 12" diameter 5-ring, 3 of the 10 shots were outside it; and 3 of those "5"s were inside the 6" diameter V-bull).

(P.S. I don't turn necks on my 1000yard .308 ammo)
 
Here's a link to an .rtf file with results from the most recent Palma match, which is the world championship of long range team rifle shooting (teams of 16 shooters, coached, prone with iron sights and sling, who fire 15 shots at 800, 900 and 1000 yards, each day for two days).

The Brits usually win the Palma match, and they did it again in Brisbane in 2011. Look at the 1000 yard scores in that file (for reference, in a 15 shot string the highest possible score is 75-15V). These are some of the best shooters in the world, firing under some of the best coaches in the world. To score a "5" on a shot, the shot has to land inside a 20" diameter scoring ring. To score a "V", the shot has to be inside a 10" diameter scoring ring.

A couple of them achieved scores of 75. But the *average* 1000 yard score was 71 points and 4 or 5 Vs (so in an average 15-shot string, 4 points would be lost by landing shots outside of the 20" 5-ring, and about a third of the shots would be inside the 10" V-bull)
 
caramel said:
Turning the neck is very important, i do it as a standard procedure on all my reloads...JP.
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I was doing some loading for my gas gun for the first time last night and tried out the crimp die that came with my che...inexpensive Lee die set (they sure feel cheap but much to my suprise I've been getting consistant results with the seater, less screwing about than my RCBS :eek:). I had read somewhere that consistant neck tension can also be acheived by crimping. I fiddled around with it a bit last night and found you can put a very light crimp on the loaded round. If you have a good load but your ES is high can you try a very gentle crimp to give uniform neck tension?
 
There was an interesting article in this month's Precision Shooting magazine that chronicled the changes in group size simply by changing the number of shots fired. I mention this to point out the fact that while the occasional tiny group is possible, it generally isn't the norm at those distances. - dan
 
It's OK to listen to Dan, but advise against debate on numbers. It is rumoured that he calculated the water flow per minute over Niagra falls. Serious numbers geek and Candian TR champ.

SD below 10 is often mentioned for longrange.

Regards,

Peter
 
redshooter said:
I was doing some loading for my gas gun for the first time last night and tried out the crimp die that came with my che...inexpensive Lee die set (they sure feel cheap but much to my suprise I've been getting consistant results with the seater, less screwing about than my RCBS :eek:). I had read somewhere that consistant neck tension can also be acheived by crimping. I fiddled around with it a bit last night and found you can put a very light crimp on the loaded round. If you have a good load but your ES is high can you try a very gentle crimp to give uniform neck tension?
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Yes you can. The key with most things you do during reloading is finding what works for you and applying that consistently. Some years back I did a 500+ round test using the Lee crimp dies in 308 Win, and in that test, with those components, the crimped rounds were more accurate in 8 loads out of 10. I still crimp for that caliber in that rifle. I tried the same test in 223 and it didn't make nearly as much difference, certainly not enough to bother with the extra work. FWIW - dan
 
dan belisle said:
Yes you can. The key with most things you do during reloading is finding what works for you and applying that consistently. Some years back I did a 500+ round test using the Lee crimp dies in 308 Win, and in that test, with those components, the crimped rounds were more accurate in 8 loads out of 10. I still crimp for that caliber in that rifle. I tried the same test in 223 and it didn't make nearly as much difference, certainly not enough to bother with the extra work. FWIW - dan
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How did the die stand up over time (it is for the gas gun afterall), or is there a more durable one that works in a similar way? It doesn't look very strong, if they ware quickly I think it's time to stock pile a few. I hate liking something and then find out they don't make it anymore.
 
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rnbra-shooter said:
100yd groups should be more or less round, and as small as reasonably possible.

For shooting iron sights with slings, if your ammo can reliably shoot 3/4" groups (5 to 10 shots) at 100 yards, this will usually be adequate.

For shooting with a scope and a rest, it can be helpful if your groups are closer to 1/2" at 100 yards.

Smaller groups never hurt of course (!), but as soon as you can achieve the above (or something reasonably close to it), you shouldn't be held back.

Another factor that does not show up in 100yd testing, is whether or not your bullet speeds are consistent from shot to shot. This usually does not matter at 100 yards, and quite often it also does not matter at 600 yards. But at 1000 yards, if the shots in your string vary by (say) 50fps from the slowest shot to the fastest shot, what tends to happen is that the slower bullets will land lower on the target than the faster bullets.

For iron sights shooting at 1000 yards, if the Extreme Spread (difference in speed from your fastest to slowest shot) in a 10-shot string is more than 50fps, you should do what you can to reduce this to be less than 50fps (if your chronograph shows you Standard Deviation, this is equivalent to an SD of about 16fps).

For shooting with a scope and a rest, it is useful to try to get your ES to
35fps or less (SD of 12 or less).
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I understand Extreme Spread. Now what is the difference between Extreme Spread and Standard Deviation? I would like to know how an Extreme Spread of 50fps can equate to a Standard Deviation of 16fps. Not trying to be smart just am now at the point in my shooting where I need to get familiar with all this. Good thread.
 
Pescado said:
I understand Extreme Spread. Now what is the difference between Extreme Spread and Standard Deviation? I would like to know how an Extreme Spread of 50fps can equate to a Standard Deviation of 16fps. Not trying to be smart just am now at the point in my shooting where I need to get familiar with all this. Good thread.
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Standard Deviation is a better statistical measure of how a series of numbers varies. Tthat wikipedia page has the math of it, but it probably isn't terribly interesting or useful. The takeaway is, "SD is a better measure of the variability of a shot string, but ES is easier to calculate"

As a practical matter, for most real-life samples of muzzle velocities, it will usually be the case that the SD of the string is about one-third the ES of that string. The attraction of ES is that it's easy to calculate (find the difference between the fastest and slowest shot in the string).

Here is a list of 10 random numbers (normally distributed, for the statisticians in the room....) that I just generated on my computer: {2900., 2906., 2893., 2903., 2895., 2907., 2884., 2891., 2942., 2898.} Consider these to be (simulated) chrono readings.

The StandardDeviation of that sequence is 15.7

The slowest shot is 2884 and the fastest is 2942, so the Extreme Spread is 58.

The ES is "about 3X" the SD (Actually in this particular case, 58 is 3.7X bigger than 15.7, which is a bit of an outlier to my "about 3X" guideline but I am going to leave it in as an example of real life "noise" that is part and parcel of actual statistical samples. In subsequent "tries" I got results of 2.92X, 3.02X, 3.24X, 2.64X etc.... ). That's another, VERY IMPORTANT stats lessons - things fluctuate!

I have (cheapy) chronograph that reports mean speed, and both SD and ES. I write all three down in my ammo log book - the above I would record as "2902/58/15.7", which means an average speed of 2902fps, an ES of 58fps and an SD of 15.7. This is ammo that I would be willing to shoot at 1000yards if I didn't have any better ammo on hand, but it is a bit sloppy; call it the bottom end of "acceptable-but-not-great 1000 yard ammo". I would absolutely shoot it in competition at 600 yards without hesitation, even at a national championship.
 
Thanks for the comebacks on Standard Deviation. I've always just tried to concentrate on keeping my ES low, which I guess , if done successfully will also keep your SD low.
 
BCBRAD said:
What kind of ,size and shape, of a group @100yds do I need to consider a shot at 1000yds to be competitive?
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Hey Brad
heres my take on your question.
If your gunning for the 1000 yd shoot in Burns Lake, the winner was a 3 inch group at 1000. So that would dictate a .3 inch group at 100. But .3 at 100 is a tad large for todays shooters. I've witnessed some .16 and .21 inch groups at 100 yds. 100 yard 3 and 5 shot groups should be 1 hole. Windy days a little horizontal stringing is allowed but no vertical stringing should take place. Best thing is to go out and practice, shoot with better shooters brings your game up!!
Shooting at 100 there are less variables affecting the bullet. Shooting at 1000 and a gust of wind could move your impact 30 inches. Practice reading the wind as well. Nokomis shooters had a wind clinic one day and I am forever indebted for the wind lesson. Call it, shoot, see actual impact.
All other variables can wait.
 
redshooter said:
How did the die stand up over time (it is for the gas gun afterall), or is there a more durable one that works in a similar way? It doesn't look very strong, if they ware quickly I think it's time to stock pile a few. I hate liking something and then find out they don't make it anymore.
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The first one lasted a decade or so, still using the second. - dan
 
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