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Im working up loads and found a load that measures .89. The problem is all three holes are just touching or very close in a lateral or flat line. Whats the best way to tune this group? If I could just move either outsiide bullets inside my group would be very respectable.

Shoot the same load again, and again, and again, … Then report back.

Three shots is meaningless.

Shoot 5 shots at least per group when doing load development. That will tell you more than a single 3 shot group. Then what you are looking for is a round group.

Or 7 shots

Vertical stringing (consistently) is usually indicative that a powder increase is needed.

I'm going to respectfully disagree with that. If you're a hunter, it's the first shot from a cold barrel that counts anyway. The following two confirm that the first was no fluke. More holes after that aren't necessary. I've never taken 5 shots at anything but paper.

Terry Wieland (I think) had an article about shooting multiple 3-shot groups on targets superimposed on top of each other. You end up with a 3-, 6-, 9-, 12-shot mix; however much you think it takes.

Appears to be workable, if not the best for someone who’s just about to turn 71 and with a gammy leg.

Takes a lot of walking…….

You are both right. 3 shot groups are meaningless statistically for load development but once a rifle's accuracy is verified, sighting in for hunting can be accomplished with only 3 shots.

Starting from the start...what are you using for wind indicators?

Good shootin' -Al

Starting from the start...what are you using for wind indicators?

^^^^^This.

Here's another example of a problem with "reading groups," in particular 3-shot groups.

These groups were fired on the same day from a custom 7x57. It was a relatively calm day, but I still used wind-flags--and let the barrel cool down between groups.

They looked like pretty nice 3-shot groups, but then I superimposed each target on an unshot target, and drew a line around the inside of each bullet hole. The resulting 9-shot group is not just considerably larger (due to statistical probability) but the three groups obviously vary somewhat in apparent point-of-impact. A professional statistician I have corresponded with--a rifle loony who's done considerable research on stuff--says he found the center of 3-shot groups varied about .7 inch from group to group at 100 yards.

Now all of this doesn't really mean much to most big game hunters, because big game is by definition large, and some variation in group size (or group point-of-impact) doesn't matter much when the chest vitals of even a pronghorn are the diameter of a volleyball, and the average hunter rarely shoots beyond 300 yards.

But it does illustrate why trying to "read" anything from one 3-shot group doesn't work very well.

So what you get when you impose them is a gun that’s not very accurate. I have noticed that on many occasions one has to move your point of impact a couple clicks to get rezeroed. For hunting it means nothing but for competition it’s a big difference. It’s just shooting variables. Edk

Lol, read this thread. It will make your head spin.

https://www.24hourcampfire.com/ubbt...s/18014723/group-statistics#Post18014723

Natural variance due to shooter...............LOL

MM

This is not about shooting game animals. You may want to re-read the op's first 4 words: "I'm working up loads".. This thread is not about what you do when you have confirmed a load. It's what you do when you have an issue with a load, or rifle presumably. When "working up loads", often times 3 shots does not confirm anything.. The only time I'll really use them is with magnum rifles, then I'll shoot multiple 3 shot groups and then a 5 shot group to confirm that it is trustworthy. Other than that, pee shooters, varmint rifles, precision rifles, and most of my hunting rifles get 5 shot groups for load work up.. Some even 10 shot groups for better confirmation. When it comes to reading groups and you are slinging 3 shots, they better all be touching or be a very nice equilateral triangle. On a "confirmed" load, I'll use 3 shots to check zero and POI at distance, but this is not about what we do with a confirmed load. Another reason 5 shots are better is because you will see if your load is double grouping. Sometimes that means you need to shorten the OAL, or add a little more powder. 3 in 2 out is considered double grouping. Hence the reason I suggested the OP shoot 5 shots per group. This goes without saying as well, but I'm going to say it. I'm assuming the OP's rifle is properly glass bedded and scope mounts loc tited, torqued and rings in perfect alignment. Scope should also be a verified "proven" scope and rifle "proven" it's accurate/precise with another load. Also, when I say accurate, that means that POI does not shift around regardless of how its sitting in the bags, bi-pod, or front rest and we can all assume the rifle is on a nice steady bench and the shooter knows what he is doing. If the shooter is at fault, there is nothing we can do about that.

Exactly.

Except for the fact that a 9-shot group under 2" is very accurate for a typical light big game rifle. Which is what many shooters/hunters don't realize--because as Jim Carmichel once stated, most "pet loads" for hunting rifles are based on a single 3-shot group.

Which is exactly what many of todays hunters do--after ONE half-inch groups, which is what their buddies brag about--and these days consider barely adequate for shooting whitetails out of a box-blind at 200 yards.

Here's another photo, of 100-yard groups shot working up loads with my 6mm PPC benchrest rifle--which with scope weighs right at the 13-pound limit for "heavy" bench rifles. If I recall correctly, these were 4-shot groups, which I prefer to 3-shot when working up loads for anything other than big game rifles. Please note that they still have different POIs:

I like 5 + shot groups for all the reasons stated plus it’s so much easier to determine the center of the group for a final scope adjustment. Those apps that measure group size, like Ballistic X will give you the center of the group and the scope adjustments needed to center the group on the center of what you are aiming at.

JB, didn’t you have a formula, like a 1” 3 shot group will open up to ~ 1.6” with a 5 shot group? 5/3 = 1.6

Mrs. Ponsor's third grade - we had two reading groups: the robins and the bluebirds.