A good day . . . for me, anyway

[Montana Pete]

About two weeks ago I shot four five-shot groups at 200 yds. Rifle was my factory-issue Savage Model 12 Varminter in 22-250. There was a slight breeze crossing from left to right.

All four groups were within one MOA, and two groups were just barely under 1/2 MOA -- in other words, just a fraction under one inch. I will show one of them -- see photo.

Improvement occurred over previous outings due to stumbling onto the Sierra 60 gr. flatbase HP bullets, which the rifle seems to like. My load was moderate -- just 29 gr. of IMR 3031. The rifle seems to like loads a couple of grains under maximum.

I know many out there do better than this. This is a benchrest forum, after all. However, for me, this was like climbing Mount Everest.

I am finished with experimenting for a while. I will just load up this same load for a while. I have just ordered a Sinclair concentricity guage, and already use an O.A.L. guage with a bullet comparator. With my new guage, maybe I can shave this a tad more. Who knows?

Thanks for letting me share this with you - - - - I am a regular reader of this forum and have learned a lot here.

Montana Pete

 

[alinwa]

Nicely done! Now you've got a 200yd squirrel gun.

Judging by that group you are ready for some flags.... I feel that your gun is starting to show it. May I suggest some 4' wood stakes w/surveyors tape? Or you already were watching the wind and it was a little less slight than you thought!???



Now, please keep lots of notes and find out if that concentricity gauge etc REALLY help.

This is how new BR guys are made...

Have you tried Bergers???

al

 

[CYanchycki]

Montana Pete

I have found that Sierra bullets usually were my bullet of choice when it came to accuracy in a Varmint rifle.

Good going.

Calvin

 

[brian roberts]

I dunno, the cheapest................

concentricity guage I saw at Sinclair's was $99.95, that's ALmost a sleeve of primers.....Oh! oh, oh, I forgot, 1,000 will do you for a year, thass' right, if ya cut down on primers, you can get some ancillary equipment. If you try a different target, Pete, you'll get that rifle to shoot a bit better, too. Try it, you may find it works.

 

[alinwa]

I can't agree about changing the target. I think a series of concentric rings is the ideal aiming point. How else can guys shoot groups measured in hundredths of an inch? I'd sure hate to be aiming (trying to aim) at something composed of straight lines!

al

 

[brian roberts]

Its easier than you think, especially..............

at short range. Yes, you can do well on the br target, because it is mosly white, and the rings don't take up as much space. I was referring to the fact that there are better over-the-counter targets available in the absence of the competition target. Try it, for load development and sighing-in, more than one person has commented on how it increased their accuracy.

 

[Latigo]

Nice shooting Montana Pete!
I've been using Sierras too, but I recently came by 1,000 Berger VLDs for my 22-250 so I'm messing with those now.

I'm new at this kind of shooting, but when we're developing load data we always deliberately shoot 1 to 2" high in the 1 o'clock position so its easy to see our groups through the spotting scope. We produce our own targets on the studio wide format digital printer.
We can program any kind of target with or without concentric circles. Some are for 100, some for 300 and others for 500 and 1,000 yards.
I like the ones with a solid center and black rings with enough white showing to see the off-center groups. We'll usually print targets in groups of 10 or 14 so we don't have to go downrange so often.

MP, have you done any fooling around with hBN in your 22-250?

Latigo

 

[Montana Pete]

Thanks much for the feedback and comments. As for targets, I WILL experiment with targets as you guys suggest.

One thing I can say is that orange and white are great for seeing .224 bullet holes at 200 yds. Using targets with black and white, I cannot see black holes against black even with my 60X spotting scope. The range uses a backstop backing that's a kind of black rubber sheet. With the black targets, the guy is trying to see black holes against a black paper.

I really like Latigo's suggestion to crank the scope so the holes appear in a white area of the target, not the black. If that is done, black targets would work fine.

Thanks again for all the comments and suggestions.


Montana Pete

 

[Latigo]

Thanks Pete. It really does make sense. When you're developing data a bullseye means nothing at all. Only the group counts. The bullseye has it's place in competition, but not for my data gathering.
For me a test group is a five round minimum. Proving it is 5, 10 round groups on 5 targets. A logged load here is 25, 5 round consistent targets and then we assign it to that particular rifle by serial number.
I'm going to have to learn how you guys do this.
Thanks

Latigo

 

[Montana Pete]

Latigo--

There is a certain "random walk" to dispersion when shooting groups.

If the rifle is held exactly the same over several groups, the random dispersion will somewhat vary the size of your groups.

Variation from the exact dead center will fluctuate. A numeric value can be assigned to this fluctuation.

That is why it is so tricky for people to shoot just one excellent group. They are so "up" and so excited. But . . . maybe they hit the statistical "perfect storm"?

Maybe for that particular group, the random fluctuation just happened to work in their favor.

For those who understand graphing and mathematics, you can set up a computer program to assign randomized numbers to an X axis and a Y axis. Set the fluctuation parameters at a certain value. The program can then "shoot" and graph imaginary groups.

You will get a lot of variation in the resulting graphs.

From time to time, you will get a small group. Does this mean you have a 1/2 MOA rifle?

Dream on.

I think you are entirely right to shoot 25 rds in five groups and then plot the average.

How do you allow for human error? Everyone can pull a shot once and a while.

 

[Boyd Allen]

Looking at your group, it seems to me that there is some wind induced horizontal. This is not a criticism. You were probably not using anything to look at the wind, and if you had been, your group might have been smaller. One does not need fancy flags and stands. Some sharpened 1 x 2s with surveyor's tape affixed to one end will do fine. Give them a try, perhaps four. Obviously, you are doing something right in the preparation and shooting of the rifle, and load development.