Okay now that I have real internet again, I have a couple of points to make.
- 3 shot groups, particularly in isolation, do not give enough information to infer the true precision of a rifle. What is the true precision of a rifle? The maximum deviation of shots absent shooter error. A 3 shot group, from any particularly half-decent rifle, is likely to be much smaller than the maximum group size or "true precision". Look at Distant Stalker's target. In this case, there may be other factors that cause the apparent "POI shift" of the groups, but regardless it's a perfect example: multiple three shot groups that taken in isolation are ~*half moa*~ but when overlaid to give a truer picture of the precision of the rifle (more information!!) tell a different story. There's human error causing poi change (probably more than most shooters on here would like to admit), there's rifle error causing apparent POI change (again, possibly more than most would like to admit from their "half moa rifle"), and there's a combination of the two which is what we all will likely see. A single 3 shot group, even if it is "half moa" doesn't mean your rifle is a half moa rifle. Even multiple 3 shot "half moa" groups don't mean that necessarily, unless you take them in totality and compare mean displacement from point of aim. Firing multiple groups on one piece of paper allows you to compare them, and forces you to be honest with YOURSELF which is important, as it's too easy to handwave things in favour of the more ideal outcome...
A picture:
Hopefully this illustrates my point. A picture tells a thousand words...
- Next point: why should we care if our rifle is ~*half moa*~ or not? It may functionally shoot half moa 3 shot groups from a certain perspective, but does that mean we can hit a half moa targets? From a practical standpoint, that should be more important. In anything where we're trying to truely measure the precision of the rifle, ie competition or load development, wouldn't we want to do it in a way that gives us more information? It's become such a ridiculous point of pride to shoot pretty groups though that the end goal of actually getting information from them is often lost. Ie a forum member whom shall remain nameless not firing a fifth shot so as not to "ruin the group". Well you're not shooting a competition so the group size doesn't count for your score, what information are you looking for that a 5th shot would ruin it? If finishing your group would "ruin it", why were you shooting a group anyway as that's obviously not the best way to go about it? Obviously groups do help with information such as mean point of impact for zeroing, and obtaining the precision of a load for load development - but the more information for these, the better, to do it properly. I can't count the number of times I've seen people at the range shoot 2 or 3 shot groups to zero and been chasing their zero around the page. A combination of lack of information about true mean POI and bad shooting? Most likely. I think the internet has also fucked with expectations in that everyone posts pretty hand selected 3 shot groups. Internet group syndrome.
-Shooting groups is different shooting to hitting things. Again see Distant Stalker's targets. If we take his statement that it was his shooting causing the change in POI at face value, that tells us that regardless of whether you can shoot a nice ".5 moa" group, or 6 of them, it doesn't actually mean a damn thing in regards to HITTING things. But the emphasis on the internet and in magazines is all on "look at this 3 shot tiny group". When was the last time you saw someone posting about trying to improve the consistency of their shooting or asking how to?
This is actually a very good practical discussion and it'd be great if we could keep it that way please
Nice... I like the look of that overlaid group.
I guess "Precision" is based on what level of "Precision" you need.
Say I want to shoot small Varmints at ranges in excess of 300yds... I guess this requires a tighter level than the bush hunter shooting Deer to 200yds Max.
I also guess that we all want rifles that put one shot after the other in the same hole... But we either have to be exceptionally skilled , very lucky, or very rich to do so... Maybe a combo of them all.
I am learning with each forum thread I read. I would never be brash enough to say that I'm a good shot as I don't get enoughtime behind my rifle. But, I have shot some really tight groups with factory rifles and Nikon scopes. Can I do this all the time? No... Is it mainly me that is the problem? Yes.
The problem is that most people show their tightest group.. Not the ones that were "meh"...
Thanks for your post Gimp, I shall try that out next time I have some time behind the trigger.
+1 (except I don't have any Nikon scopes, my best groups have in fact been shot with a Nikko 3-9)
Am I personally consistent enough (or shooting targets often enough) to determine whether my rifle is always capable of 0.5 MOA with the right load? No, but a high enough proportion of groups are in that ballpark (with POI where I want it) to be pretty confident, and when they aren't I usually know from my own shooting before I even look at the target. I think an accurate rifle is essential for improving your shooting, otherwise you just blame the gun!
I don't mind people posting photos of their best groups though, its like race drivers posting in-car video of a really good lap - its saying "hey I'm really happy with this one", people aren't generally trying to say "oh I do this well every time".
Last edited by GravelBen; 25-09-2013 at 02:03 AM.
Saying the overlay is a full picture/true precision of DS's rifle or him is not a fair indication, IMO. There is human error in the final overlay. A better indication would be the same amount of shots fired at the same aiming mark. Any small-bore/comp shooter, knows any change of target no matter how small requires adjustment in position to ensure MPI remains the same.
Unless his scope is buggered you only get a shift like that due to position or heat.
Do what ya want! Ya will anyway.
Yeah in the example provided i think human factors cant be seperated from rifle factors. Any change in grip, position etc can adjust poi so when rifle is mounted/dismounted between groups, moved to cool etc a poi shift between groups can be expected. I would have to shoot the test again without moving the rifle or changing.shooting position to expect to hit same poi each time. Each group is typically sho from same shooting position with same hand position and cheek weld pressure unless heat requires a quick blow down barrel and quick shot before mirage returns....
Because of this i still see the groups as independantly representarive of rifles grouping ability from that shooting position for that group. I suppose you could fire 15 shots at one aim point with consistant break between shots to avoid excessive heat and mirage but fatigue.may.become.a factor.the
Either way im confident in the precision of the rifle and becoming increasingly aware of the shifts that can occur from.subtle changes in body position/shooting technique
I'm not drawing any conclusions from your targets, but it's a great example because it shows that either your rifle is demonstrating the "apparent shift in poi" of "good" 3 shot groups within the larger precision of the rifle, or it's demonstrating the fact that shooter factors make shooting groups a lot different to "Actually hitting things" and not super relevant to it, which is something no-one ever seems to want to admit. Probably it's a combination of the two, weighted more towards shooter?
its an evolution I think, start with shooting for groups and end up at first round hits at varying ranges
I'm sure most of you have seen this pretty sure it's 5shots
Steve054 that's something to aim for
Sent from my iPad using Tapatalk - now Free
I can't imagine anything more boring that you could do with a gun than bench rest. Competitive instrument calibration
I can shoot 1 hole groups all day long
As a matter of interest how do you guys measure your groups ,Taking furthest apart holes do you measure from inside to outside, center to center , or from outside to outside then deduct the bullet diameter ?
If you want to make it really interesting, try measuring the distance from the center of each of 5 bullet holes to the center of the point of aim , then add all these distances together, this is a "string" measurement .
Last edited by Druid; 27-09-2013 at 12:34 AM.
Get as close as you can then six feet closer
Bookmarks