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Yeah, partly because that's about what I've noted when firing 3-shot groups with a rifle, then marking the group and shooting another two rounds.

The statistics guy I corresponded with said the long time American Rifleman standard of five, 5-shot groups was pretty darn good for predicting a rifle/load's consistent accuracy--but also that when using modern computer programs he'd found 6-shot groups were a little better.

It all depends on what dependable degree of accuracy somebody desires. Obviously that would be very different for the average deer hunter--or even a traveling hunter who's after elk, or African plains game--than a target or small-varmint shooter.

In which group were you?

I was a proud robin.

What if d-o-g spelled cat?

Whoa…

No matter how well a gun shoots, 5 shot groups will run about 40% larger than a 3 shot group.

Lacking even the most basic windflags, there's no load 'development' being done when you go to the range. Shooters think they've really found something only to end up scratching their head the next time out when their 'pet load' doesn't perform. Then it's rinse and repeat. And on it goes.

Even in relatively decent conditions, a single flag at 100 will get you at least 25% improvement. And often more.

Good shootin' -Al

Well I have to agree. The 2 things I rarely if ever see when people say load development at the range.
Wind flags never
Chronograph is once in a blue moon

I made up some simple 'donor' flags and toss a couple in with my gear whenever I go to the range. If there's someone there that seems to be at a teachable moment I'll put one out for them. Then, with them holding the same POA, I'll tap them on the shoulder when it's time to shoot, per the flag orientation. The results are predictable as are the smiles. The flag is gifted to them and they come up with their own poles.

The only problem is now I'm out of 'donor' flags.

Good shootin' -Al

Al
What kind of flags do you use? I can't imagine I would need them at the range I use... surrounded by trees and I never shoot when the mph is more than 5...

Quite a few people (accomplished smallbore shooters) say, if you are only going to put out 1 flag, put it somewhere between the muzzle and the halfway mark. I know it's counter intuitive, when you factor 'time of flight'...but in real world shooting for score it seems to work better when you can't shoot unlimited sighters.

Here's an old thread that might be useful.
Group shape, does it matter?

I used to put out wind flags, where I lived because it was damn windy in the gorge all the time. Now where I live, it's windy on occasion, but most times it is about 5 mph. A light wind will not mess with a group too much when you have a target set at 100 yards away. I know JB has written some articles on using wind flags, but from what I've seen, the wind has very little affect on modern bullets at short range. As for those that simply rely on a chronograph to give you numbers, well, I've seen that bite guys in the azz too. If you are working up a load, shooting and reading groups, you better bring your A game to the bench. That is the most important factor, besides knowing your rifle is mechanically sound. However, if you want to use Wind flags, they are super simple to make. But I would suggest to work up loads on a fairly calm day, vs shooting in the wind. Use surveyors tape, if you have to. Those are easy to see and move in the wind easily. Plus a roll is easy to keep in the range bag or truck. These days I just staple up my targets in a way that the wind will move the bottom corners of the paper. I use 3 staples. 2 in the top and 1 in the bottom. Its easy to feel which direction the wind is coming from at the bench and then look downrange on target to see if the bottom corner of the paper target is moving as well. In some of my long range shoots, wind flags are not allowed. I love that aspect too, because then you have to use the environment to judge the wind. A lot of guys fail that test, but when you learn to read things like a bush or grass moving downrange, or bullet splash and dust cloud direction, then you are learning real world scenarios that will move a bullet at distance. None of you guys are mentioning head winds and tail winds either, if you really want to get technical, you should delve into that in your free time. Guys don't like my targets, but this group was shot the other day when this thread started. 5 mph wind and it was the best group shot during load development:

NOTE: All groups shot this day, were sub moa.

That was from a new rifle, that I threw into a B&C, glass bedded it and scoped it with a new scope after I checked the rifle with a proven scope. Now to test the New Zeiss V4 conquest and rifle and develop some loads with unfamiliar powder and bullets:

I don't generally like to "develop" loads at 400 yards, but I figured it was too cold and slightly too windy to develop loads that day anyway. So out of curiosity, I flung some at 400 yards. Here is the result of one 3 shot group:


I also had another rifle out that day: My 6.5 Creedmoor Tikka CTR that I just put in a Mcmillan A3 stock. Also working on some loads with the Barnes match burner bullet in this rifle. Both rifles also using StaBall 6.5 powder. All new to me, but I wanted to do some testing. One load did the best at 100 yards:

Then another charge weight looked like crap, but if you lay one target over the other you are still going to have a sub moa (.831") 10 shot group:

There's that evil double grouping I was talking about earlier^^^^^^ (3 in 1 hole and 2 out). Who knows, maybe a wind gust came in from the left side? Still not enough to really concern me. I knew the wind was pretty constant though from left to right.

At 400, I put 3/4 moa adjustment in the scope to shift the POI more to the left, but that was still not quite enough:


So what does this tell me? As I had intended, and written on the targets, I will need to double check a couple loads from each rifle. I want to see how this powder does on a warmer day. Some guys say StaBall 6.5 is pretty temp stable. We will see. As for "reading" groups, I'll fire off some 10 shot groups to see what they are really doing. Once confirmed, you can then shoot your 3 shot groups. At 100 yards, those are pretty boring, but at 400+ yards, they will show you POI shift due to the wind.

Always get a kick out of the armchair statisticians ...... sample size blah blah blah. Who here can tell me how to set up an ANOVA with the variables being powder charge, seating depth, and shoulder bump?

How bout a statistical experiment to identify best brass, powder, or primer for the intended purpose?

I will throw some numbers at you.

If your wind is constant @ 5mph which my testing has shown it never is a 52 grain match bullet leaving the muzzle @ 3400 and wind 0 = no drift. So will assume that shot 1 is at 0 mph
Shot 2 with a 3 mph wind at 3 o’clock = .32” drift from shot1
Shot 3 with a 5 mph wind @ 3 o’clock = .53” drift from shot 1
Shot 4 with 8 mph wind @ 3 o’clock = .85” drift from shot 1
Shot 5 lands somewhere in the 0-8
So possible variance in the group is .85”

Now wind flags, even just surveyors tape on a 3/8” dowel placed at say 50 and 75 yards allows me to pick a condition of either 0, 3, 5 or 8 mph that is most common. Now if you judge it right and shoot the same flag condition it eliminates most of the variance possibilities.

The armchair statistics people are always talkin' about sample size blah blah blah. Regardless of sample size a confidence interval on group size can ALWAYS be calculated. BUEHLER ..... BUEHLER .... BUEHLER.

I thought so.

The real nice thing about a "constant" wind is it will not affect group size. Only group POI. Think about that one..

Yep ... but what universe are you in when wind speed is actually constant?

This may be one of the most useful campfire threads I've seen in years.


Okie John

😳

I will agree with BSA on, is that in 25 years of group, score and BR 50/50 or ARA I have never ever seen a single wind flag used at 50-100 yards. Usually there were so many of them you could barely see the ground out to the target backers. 🤣

One of the instances where flags are VERY useful at 50-100 yards is testing rimfire ammo....

If you want to get started, here's a sketch of the 'donor' flags referenced earlier. Anyone with simple hand tools can make these for under $10 with stuff from Ace Hardware. Old election or advertising signs are perfect for the Corroplast. But it's dirt cheap at Staples or anywhere that makes signs....lots of times they have scrap pieces they'll give you or sell for a couple bucks.

When you start using flags, two of the first myths you'll find dispelled are the 'steady wind' and 'dead calm' myths. There's no such thing as a 'steady wind'. Ever. Period. Ditto for the 'dead calm' stuff. After you shoot for a while over flags, you'll realize that a condition that feels like a 'dead calm' is anything but.

Good shootin' -Al