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Then, I had an interesting experience. I was shooting incremental charges to identify the best group and something very interesting happened. One charge, 22.3 gr, with Sierra 77 gr MK bullets gave the following results.

5/15/2021 - 0.344 MOA

5/16/2021 - 0.287 MOA

5/17/2021 - 0.315 MOA

5/19/2021 - 0.315 MOA

On four separate days, I had four groups from the same charge produce four three shot groups no bigger than 0.344 MOA! What more could one ask for!

**Unfortunately, the story doesn't end there.**

So I focused only on the 22.3 gr charge and loaded up a bunch of rounds. I would shoot these as 3-shot groups. This is where things took a surprising turn. The first group was,

0.478 MOA

No surprise here, we pretty well know that 0.3nn groups were going to spread some, so 0.478 is not a surprise.

The next 12 groups were mind boggling - what is going on! How do we get from four days in a row of 0.344 MOA max to a group over 1 MOA??? And, as you can see, interspersed among all the groups are a couple of 0.3nn groups. Very strange.

0.869

0.783

0.879

0.840

0.716

**0.382**

1.051

0.669

0.802

0.907

**0.334**

0.879

As I thought about this, it occurred to me, how easy it would have been to stop at the four amazing groups and declare that the best charge. However, when I plotted all the charges, here's what I got,

**That charge that started out so amazing, turned out to be the worst of all the charges!**

Of course, I had many more groups with the 23.5 gr charge than all the others. That prompted the thought if I had shot the same number of groups with the other 6 charges, would they spread out too?

**And there's the question!**

If we were to shoot a large number of groups with every charge would the group sizes sort of even up or would one charge show up as a distinct best performer?

**So, guess what we're going to do!**You guessed it - we're going to shoot a bunch of groups at each charge and see what happens!

What I'm looking at right now is shooting 20 3-shot groups for 7 charges. I'd like to do 30 groups but that's just a bit much. 20 3-shot groups for 7 charges would be 20 x 3 x 7 = 420 rounds!

This will take a while, about 20 days (one set per day). Then there will be days I can't make it to the range so this could wind up running into 25-30 days.

That's a lot and it's going to take a lot of determination on my part to stick with this.

**So what's the reward?**There are only two outcomes. One, the charges will all shoot about the same, or two, one (or two) charges will produce a significantly tighter group(s) and hand in hand with that is that some charges may produce significantly larger groups.

**The overall end result will demonstrate if rifles do prefer one load or not.**

First set (1 of 20):

First set (1 of 20):

**2nd set (2 of 20):**

This should get interesting!

**3rd set (3 of 20):**

Wow - look at the 21.5 and 22.1 gr charges! But, I've seen that before only to watch the group size grow and grow. As Yogi says,

*"It ain't over till it's over."*😊

The groups for the 21.5 gr charge are right on top of each other, but the 22.1 charge has slightly tighter groups.

**4th set (4 of 20):**

That 21.5 gr and 22.1 gr groups are hanging right in there!

They're hard to see, so here's a blow-up of the 21.5 - 22.1 charges. You can barely see the four group symbols they are so tight!

**5th set (5 of 20):**

I don't know if there's a limit on how many pics can be posted in one post, so in order to minimize post counts, from this point forward, I'll make the pics larger in hopes that will eliminate the need for additional zoomed in pics like the one above.

**BTW, if there's any doubt how many dots you should see per charge, you can look to the legend at the right and count the dates. That's how many dots you should see per charge.**

So far, the pattern continues...

**6th set (6 of 20):**

This chart is a bit different. Because of the number of groups, things were starting to get cluttered. So in an attempt to help with that, I changed the vertical axis from 0.0 - 1.7 MOA to 0.1 to 1.4 MOA. That helps to spread things out a bit.

I also added blue bars representing the average group size for each charge. The bars are hard to see in some of the groups.

With 6 sets in, a trend is developing. I'll likely do two more sets tomorrow and two more sets the next day which will bring the set count to 10. If I don't see a significant change, I'll likely stop at 10 sets.

**7th & 8th sets (8 of 20):**

Quite a few things going on here. I have now dropped both the 23.0 gr and 23.3 gr charges because they were so diverse I could not shoot enough to make the group spread any smaller. Hence, it would be a waste of time and resources to continue shooting those two charges. The same is also true of the 22.4 gr charge, but it was a lot easier to drop the 23.0 & 23.3 charges from the chart than it would be to drop the 22.4 charge, so I just left it.

You can see the chart now only shows the lower 5 charges.

In post #21 I posted that I was not going to count set 7 as shot because I had to shoot it on a different range. However, when I shot the next set on my regular range, I could see no rationale to drop or re-shoot set 7, so it counts after all.

Another thing about this chart is that 22.7 gr charge. If it were not for that one group shot on 6/8/2021, that charge would certainly be a contender. I tried dropping the high and low groups for the 22.1 gr and 22.7 gr charges to see how that looked - I was surprised to see it looked worse than not dropping them. Still that 22.7 gr isn't that bad. That one group is well under 1 MOA and the rest are under 0.65 MOA!

While the trend remains pretty much unchanged, there is a slight change in charge 22.1 gr. It is growing but by tiny amounts. That is not surprising. I now have 24 shots per charge and the more one shoots, the larger the group is going to get

**until we reach a group size that all shots will fall in.**I don't know what that is for the 22.1 gr charge, but since 30 is considered an adequate sample size, I'm not far from that at 24 shots. Two more sets will put me at that statistical threshold. So whatever the 30 shot group is, I'm gonna call that good!

**More about that when I'm finished.**

When I started this I was thinking about 20 - 30 3-shot groups. But when I realized, altogether I'm approaching 30 shots per charge, the aggregate effect is 30 shots of one charge. That's enough!

**Maybe only two more sets to go! 🙂**