How to analyze this 22LR group?

[Sailor757]

Background: I intended to move my target all the way out to 150 meters, in ten meter steps, and get a ballistic curve of the bullet. The cartridges are standard .22 lead, bought 20 years ago, oiled, not waxed and packaged in 500 round cans.

The first group (above) is shot at 50 meters and the second (below) at 60 meters. It was a no wind condition.
Rifle used is an Anschutz .22LR hunting rifle in good condition.
Scope is an I.O.R Recon 4-28.

I aimed at the center of the black square.

First group was easy, I was sitting at a table with bipod, aiming. The rifle settled, I watched the crosshair move just a little (within a centimeter) until the shot was fired.

The next group confuses me. Sure I walked down to the target, it weighed 50 pounds and I carried it 10 meters downrange. I had to walk 70 meters in a slope back to the shooting table. I had some extra pulse and I noticed that while watching the crosshair. During the 4-5 seconds of aiming that lead up to each shot, the crosshair bounced a bit from the heartbeat but still kept within an inch. I could see that quite well since I was at 28X magnification. As far as I can tell, the trigger pull was slow and steady all the way. It was supposed to be a 3 shot group at 60 meters, but I ended up using 13 rounds until I realized it doesn't get any better.

What to do? I have never in my life been outside 2 inches with a rifle at 100 meters and this was just 60 meters. Maybe you can explain what could have happened here?

I will try again in a few days. My goal is still to get out to 150 meters and produce a diagram of that.

 

[NIGHTLORD40K]

Is it a full Mannlicher-style stock? Though Ive never heard of a .22LR doing it, centerfire full-stocked rifles are known for wandering as the barrel heats up.

Only thing I can think of, other than downrange crosswinds or loose scope mount.

 

[Sailor757]

It's a regular stock, it doesn't go all the way out.
I will check the scope mount.

It's still possible that it somehow was ME doing this. But I don't understand how.

Is it a full Mannlicher-style stock? Though Ive never heard of a .22LR doing it, centerfire full-stocked rifles are known for wandering as the barrel heats up.

Only thing I can think of, other than downrange crosswinds or loose scope mount.

 

[Picher]

Possible reasons:

Canting rifle stock
Jerking trigger
Front rest under barrel instead of stock
Forend touching rest instead of bag
Front sling swivel touching bag
Change of stock pressure against shoulder
Barrel heat
Loose stock screws
Loose scope mount
Changing pressures against stock
Insufficient or inconsistent holding
Ammo change

 

[Captcurt]

Picher covered it well. I would try several brands of match ammo. I ran test with a couple of my rifles and found a big difference in group size. One was a Winchester 52B Sporter and the other a CZ453. The 52 liked Federal Gold Medal and the CZ liked Wolf. I ran several different brands through both including CCI Green Tag, Lapua, Federal GMM, Wolf Match, Federal Champion, CCI Blazer, Winchester Power Points, and CCI Mini-Mag. Groups shot at 50 yards ran from dime sized to 2".

 

[Varminterror]

The group tended low and left. That’s typically caused by increasing shooting hand grip pressure during trigger pull or “punching” recoil with the shoulder.

Was this fired with just the bipod, or a rear bag support as well?

 

[Slamfire]

Background: I intended to move my target all the way out to 150 meters, in ten meter steps, and get a ballistic curve of the bullet. The cartridges are standard .22 lead, bought 20 years ago, oiled, not waxed and packaged in 500 round cans.

The first group (above) is shot at 50 meters and the second (below) at 60 meters. It was a no wind condition.
Rifle used is an Anschutz .22LR hunting rifle in good condition.
Scope is an I.O.R Recon 4-28.

I aimed at the center of the black square.

First group was easy, I was sitting at a table with bipod, aiming. The rifle settled, I watched the crosshair move just a little (within a centimeter) until the shot was fired.

The next group confuses me. Sure I walked down to the target, it weighed 50 pounds and I carried it 10 meters downrange. I had to walk 70 meters in a slope back to the shooting table. I had some extra pulse and I noticed that while watching the crosshair. During the 4-5 seconds of aiming that lead up to each shot, the crosshair bounced a bit from the heartbeat but still kept within an inch. I could see that quite well since I was at 28X magnification. As far as I can tell, the trigger pull was slow and steady all the way. It was supposed to be a 3 shot group at 60 meters, but I ended up using 13 rounds until I realized it doesn't get any better.

What to do? I have never in my life been outside 2 inches with a rifle at 100 meters and this was just 60 meters. Maybe you can explain what could have happened here?

I will try again in a few days. My goal is still to get out to 150 meters and produce a diagram of that.

View attachment 1006542

If you only experience of shooting is centerfire, then the horrible ballistics of 22 lr ammunition will be almost inconceivable. I have been shooting Smallbore Prone about a decade now, and it takes lots of matches to figure out, wind moves the bullet one heck of a lot. And it is not even wind you see. Or at least I can see anymore with irons. Last smallbore prone match, at 100 yards, my bullets are moving all over the place, the wing flags seemed predictable, and hardly moving. On my right was a former National Champ, on my left was a guy on the American Team to a UK smallbore event. End of 100 yard match, one was telling the other, he had put on half a MOA, and it was moving, the National Champ was said he ended up with 1 MOA of windage. I never saw it.

It was not till the targets were at 50 yards, and the sun came out, that I saw any mirage, and it was twitchy, left to right. Then it would stop, and go right to left. The flags barely moved, and yet, bullet drifted with that mirage.

Go put out a lot of wind flags, use your scope to look at the mirage, and you will start to see correlations to wind velocity, movement and bullet drift. However, I have seen many times the wind flag in front of my target just flip, for a second and drop, and that was enough to blow my bullet way out of the ten ring. Wind is neither predictable nor constant.

The Range Gods are laughing . Just when you think you have it all under control.......................

 

[Dr T]

Note that you just walked back uphill to the rifle. Biathlon is a very impressive Olympic event for a reason...

BTW. I would suggest you use different identical targets for each distance. Calculate the center of mass of the group. Measure from the aim point of the target. and EXPECT A LOT OF NOISE in the measurement. For a three shot group, use the centroid:

 

[Sailor757]

Possible reasons:

Canting rifle stock
Jerking trigger
Front rest under barrel instead of stock
Forend touching rest instead of bag
Front sling swivel touching bag
Change of stock pressure against shoulder
Barrel heat
Loose stock screws
Loose scope mount
Changing pressures against stock
Insufficient or inconsistent holding
Ammo change

Great! I will go through the checklist at the range tomorrow.

 

[Sailor757]

The group tended low and left. That’s typically caused by increasing shooting hand grip pressure during trigger pull or “punching” recoil with the shoulder.

Was this fired with just the bipod, or a rear bag support as well?

I only used bipod. Haven't got a rear bag yet, so I supported with the hand.

About hand grip pressure, that rings a bell. I'm more a handgun shooter than rifle. Earlier, groups were often low and left when shooting handguns. By improving the grip (Applying pressure also with outer parts of the fingers to the point they cant move during triggerpull) and also tensing the wrist, low/left groups are now mostly gone.

With a rifle I'm honestly not sure what the best grip is because you can't reach all the way around like you can with a handgun. If someone can describe how a good grip with the firing hand should be for rifles it would be much appreciated.

 

[Boomholzer]

Let the front and rear support (your off hand) do the work. Rear bag or not. Your booger-hook hand (and wrist) should be relaxed and supporting the pad of your finger for a size perpendicular or square purchase on the trigger shoe in the middle of your pad. You generally need your cupped palm and that loose opposable thumb, not a firm grip.

I would also inquire in what your offhand was doing for support and how/if you load the bipod. I would then ask how much correction it took to set up for the next shot, even with a 22LR. Did you shift your butt, did you have to slide the bipod a bit back to the side? Did you need to lift you head or lose the target?

Is the table familiar? What is this table? Is is a shooting bench? Even with a shooting bench, many are totally incorrect geometries outside of using a sled. I'm more a prone shooter so the argumentative aspects of ad-hoc table shooting are easy for me to pick out.

 

[Picher]

Practice, practice, practice:

 

[Sailor757]

If you only experience of shooting is centerfire, then the horrible ballistics of 22 lr ammunition will be almost inconceivable. I have been shooting Smallbore Prone about a decade now, and it takes lots of matches to figure out, wind moves the bullet one heck of a lot. And it is not even wind you see. Or at least I can see anymore with irons. Last smallbore prone match, at 100 yards, my bullets are moving all over the place, the wing flags seemed predictable, and hardly moving. On my right was a former National Champ, on my left was a guy on the American Team to a UK smallbore event. End of 100 yard match, one was telling the other, he had put on half a MOA, and it was moving, the National Champ was said he ended up with 1 MOA of windage. I never saw it.

It was not till the targets were at 50 yards, and the sun came out, that I saw any mirage, and it was twitchy, left to right. Then it would stop, and go right to left. The flags barely moved, and yet, bullet drifted with that mirage.

Go put out a lot of wind flags, use your scope to look at the mirage, and you will start to see correlations to wind velocity, movement and bullet drift. However, I have seen many times the wind flag in front of my target just flip, for a second and drop, and that was enough to blow my bullet way out of the ten ring. Wind is neither predictable nor constant.

The Range Gods are laughing . Just when you think you have it all under control.......................

Well, the wind was weak, but directly from the side. I can try windflags next time. Didn't think the bullet could be much affected by weak wind at only 60 meters distance. Since it drops almost an inch from 50 to 60 meters, you may be right.