How to read Groups

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Ned Kelly
.270 Winchester
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How to read Groups

Post by Ned Kelly »

G'Day All,
after last weekends, Mexican get-together, i realised that most people dont know how to interpret the info you can get from your groups. So i took some photos to show you what you can see if you look.

Image

This group was 5 shot with a 6ppc at 100yds in an average 10mph crosswind. what it doesn't show is me aiming off by 1 ring (6mm/0.25") left or right to compensate for the wind strength and still continue to hit the centre of the group. Also, this shows the typical 1/4moa vertical that Little River seems to award any shooter when they shoot there. this is what all shooters are usually trying to achieve, a nice round group.

Image
This group was 5 shot with a different BR rifle again in 6ppc, notice there is actually 2 groups in one, each overlapping the other. Why?, miss reading the wind. Also, this barrel has had over 3000 rounds through it and I consider it to be not competitive for BR anymore, notice it looks a bit ragged compared to the previous group. that barrel was rechambered after 1800 rounds so it is relatively fresh.

Image
Now this target sheet has what appear to be terrible groups. These were shot by people who have never shot a BR rifle before. The groups will be called 1-6 starting from top left to right and bottom left to right. Look at grp 1,5 & 6. See any pattern? They all slope from 9:30 to 3:30 across the target. This is a typical wind pattern, most of the shooters said they did not watch the wind flags, if they could and knew how to understand the flags, those groups might have been half the size.

Look at grp #2, better wind reading but it shows 2 distinct wind strengths, bullets are cutting, the rifle wants to shoot. Also notice there is the typical Lt Rvr vertical. But more importantly, they are FLAT. This means the load is a good load and the bench technique is GOOD. Very important to understand that it is not necessarily the load thats crappy, it might be the way you hold the rifle when shooting off a bench or bipod.

Grp #5 is what we call a weather pattern, it looks like a machine gun has sprayed bullets across the target, this shooter did say that he was not watching the flags. We all have targets in our cupboard like that.

What are the lessons:
1. Your reloads should be tested at 200yds or more to see if there is noticeable vertical, if so is it the load or shooting technique.
2. All bullets move in the wind.
3. Most rifles can shoot better than the user.
4. Take more notice of the wind regardless of whether you shoot in the paddock or at paper. The wind does not discriminate, it will punish you regardless!

You may recognise some of these groups as some you have shot, some basic flags like the ones I made and we used last weekend can make a big difference to your understanding of the bullet flight and the forces acting on them.

Hope this helps

Cheerio Ned
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damien couper
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Post by damien couper »

thank of the info ned your storys allways teach me a lot just keap writing them
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Knackers
.338 Lapua Magnum
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Post by Knackers »

Thank you Ned, very informative read.
If you want to keep writing, I'll keep reading. :wink:
I have heard that you may have bedding problems if you consistantly get "two" separate groups out of the one group. ( does that make sence?)
I have this problem with my MPR sometimes.
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HAIR BEAR
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Post by HAIR BEAR »

Thanks Ned
you are a wealth of knowlage think i will need to catch up with you at the range ,next year for some more teaching !!!!

Andree
Counter
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Post by Counter »

Thanks for posting that! very helpful.
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Ned Kelly
.270 Winchester
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Post by Ned Kelly »

G'Day All,
thanks for the comments, I remember too well trying to find out about things as a varminter, so if you guys/gals are finding this helpful, that's great, because that's what's intended. :D :D

G'Day knackers,
it is possible, I suppose. The first thing most target shooters do when silly things happen is put a known trusted scope on to see if that cures the problem. Many shooters do not think that scopes, especially expensive scopes, can go sour, but they do.

Since most of my taget rifles are either glued to the stock (glue-ins) or bedded properly, I cannot say for sure. Any double groups are usually of my own making! :lol: :lol: :lol:

If in doubt ask SC as I'm sure he'll know. If you have doubt get it bedded anyway, if only to build your confidence/trust in the rifles performance.

Anyone else care to comment please?

Hope this helps

Cheerio Ned
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trevort
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Post by trevort »

thanks Ned.

I shot group 5. 1st shot whacked me on the bridge of the nose so I definetely wasnt trying to read the wind, just not get hit again!

This is invaluable info for all handloaders, not just those wanting to compete cos if you cant read what your rifle is telling you you wont necessarily end up with the most accurate load.
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Ned Kelly
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Post by Ned Kelly »

G'Day trev,
jeez mate I was trying to keep 'em guessing!

Hope your nose is feeling better! .........and hope you haven't developed a flinch :shock:

BTW, the "good groups" at the start were shot with the Bat.

The significant thing here is it was a load I have NOT used before in that rifle. :shock:

They were loads that worked very well in the old barrel on the Hall.

I have noted the powder weight, type and bullet too.....cause I reckon i'll use it again! Whoo hooo! :lol: :lol: :lol:

A good rifle, whether it is a custom build or one that has been trued and built properly can shoot average hand loads exceptionally well. They will be very tolerant and easy to tune compared to a factory rifle with more looser tolerances than any accuracy gunsmith will/should allow on a custom built rifle.

That is exactly why shooters accurise their rifles to remove mechanical errors and have precisely machined actions and barrels of high quality to shoot .3moa or better.

Food for thought!

Cheerio Ned
woob614271
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Post by woob614271 »

Good advice on all fronts Ned; if more tyro shooters had this sort of "coaching' they'd probably stick to the game instead of racking off in disgust; it's a constant learning curve; i doubt if anyone knows it all.
chris.tyne
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Post by chris.tyne »

Trevort I must say this publicly,it takes a big man to admit to being belted in the nose by a PPC! :lol: :lol: :lol:
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alpal
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Post by alpal »

thanks ned, much appreciated advice, keep em coming please.
Trev, do you shoot free recoil?
Regards Alpal
ogre6br
300 Win Mag
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Post by ogre6br »

Ned
could you use picture 3 and further explain how to read the sizing of the groups shot on that page in terms of MOA?

would any of the groups in pic 3 win the BR medals that we sometimes see listed in the back of the SSAA jornal??
silver, gold , ruby etc and what do each of those medal mean??

can any SSAA member go for that medal or do you have to be a BR clib member to earn them??

Thanks
later
p
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Ned Kelly
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Post by Ned Kelly »

g'Day Pat,
good to see you're vertical!

The flags that are angling from the 10:00 to 4:00 would cause the diagonal groups, the pure cross wind flags natuarlly give you the flat groups and if shot on different strengths you get 5 separate shots or the typical 2 and 3 shot group, sometimes the 4 and 1. If your luck holds a small 5 shotter. This simply shows how well you read the wind strength.

As for the size of the groups, each ring is 0.25" apart and at 100yds this is 1/4moa. The diameter of each ring is 1/2, 1, 1.5, 2, and the last ring is 2.5moa in size

The Benchrest Awards are open to anyone and can be seen in the BR rule book see link

http://www.ssaa.org.au/newssaa/discipli ... chrest.pdf

see pages 41 & 42 for details

This will explain everything. Your local Br delegate is Peter Van Meuers and you will need to compete in a BR club match (registered if you are going to shoot bug holes!) to get the moving backer strips to verify the number of shots in each group.

Groups #2 & #6 look to be less than an 1" so would be awarded a silver medal.

hope this helps and hope your doing ok!

Cheerio Ned
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trevort
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Post by trevort »

I am trying to learn free recoil, remember, I dont have a target rifle yet.

I fired Shanes 6.5x 284 at the Procal fly and the 1000yd the next day.

I learnt from a scope ring on the eyebrow that free recoil with a reasonable sized case needs the shoulder just off the butt to stop the rifle (as the projie will be on its way by then)

When I shot that factory rifle comp I was firing free recoil because the set trigger of the CZ was light enough to allow me. It had a Sinclair foreend adapter on that squeezes the side of the front bags and the butt wasnt exceptionally smooth thru the rear bag, It wasnt coming back at me fast.

Now I expected much the same from the pipsqueak PPC. If you put your shoulder near the butt, it does feel much the same. Problem was a proper BR rifle with a super smooth tracking stock builds up some velocity even under mild recoil. I'd never fired one before and didnt expect that. So I just looked thru the scope, adjusted the rest and squeezed before I got a smack on the bridge of the nose!

Another lesson learnt the hardway
ogre6br
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Post by ogre6br »

Ned Kelly wrote:g'Day Pat,
good to see you're vertical!

Cheerio Ned
only just- but yes- 5 Ops/procedures in the last week and I'm back to it again on the 3rd of Jan- for at least another 3 months.

unfortunately my father isn't anymore-
Dad was in the room 4 doors up from me in cancer/oncology ward at the hospital- I went home, he didn't- bummer of a week.

P
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