2 in 1 out???

[wisconsinteacher]

Can someone explain this phenomenon to me. It happens to me all the time. Sometimes it is the 2nd shot others it is the 3rd and in multiple guns. Why does it happen on a repeated basis and why doesn't the 1 out happen to group with the other 2 now and again?

 

[HeathSexton]

Harmonics I rekon


Seat them deeper

 

[JD338]

Barrel harmonics.

JD338

 

[DrMike]

Normal variation of accuracy can readily account for this. The fact that you haven't witnessed a chronological pattern would make it very hard to discount normal variation (harmonics). This phenomenon can often be addressed through adjusting OAL of your load, which is strongly suggestive of harmonics of the firing system.

 

[Guy Miner]

This is what competition shooters strive to eliminate.

Heavy, high quality barrels. Free floated. Trying to minimize the harmonics.

Very sturdy, stable stocks. Rifle action very solidly bedded into that stock.

Robust scope or sight mounting setups. Everything is nice and snug and as wobble free as possible.

Then their ammo is top notch, the best they can build or buy. They're not trying for three shot groups, like so many of us hunters do - in some sports - like NRA Highpower - they're shooting 20 shots for score at 600 yards, at the end of the match, after all the other shooting at 200 & 300 is done. Twenty shots... Can't have flyers. The match winners often shoot perfect scores, tied with other competitors, and the winner determined by X-count. They can't have flyers based on the rifle or ammo. It's all up to the shooter at that level, pretty much everyone is running good gear.

Guy

 

[wisconsinteacher]

So some of it maybe shooting magnum rifles with thin barrels and factory stocks? I understand it is harmonics, but when you shoot a few groups and they all look the same, you have to ask why did 2 bullets do this and not 1 or 3. I just don't get why it is always one.

 

[Ridgerunner665]

So some of it maybe shooting magnum rifles with thin barrels and factory stocks? I understand it is harmonics, but when you shoot a few groups and they all look the same, you have to ask why did 2 bullets do this and not 1 or 3. I just don't get why it is always one.

Murphy...

 

[Richracer1]

Murphy...

You just gotta love Murphy....NOT

 

[DrMike]

So some of it maybe shooting magnum rifles with thin barrels and factory stocks? I understand it is harmonics, but when you shoot a few groups and they all look the same, you have to ask why did 2 bullets do this and not 1 or 3. I just don't get why it is always one.

Statistical variation. Ten shot groups won't have one out; it will produce a distinct pattern.

 

[OU812]

Can someone explain this phenomenon to me. It happens to me all the time. Sometimes it is the 2nd shot others it is the 3rd and in multiple guns. Why does it happen on a repeated basis and why doesn't the 1 out happen to group with the other 2 now and again?

Others have given good explanation on what can cause it and how to possibly correct it. I think most everyone has seen this or had it happen.

How big of a group is the flyer causing?

Lets say you shoot a 1- 1.25 inch equilateral triangle group. Are all 3 shots flyers because they are not touching? If you shoot again and 2 are touching and the 3rd is out is the second shot a flyer because it didn't make an equilateral triangle?

 

[hubcap]

For a group that is say moa or slightly better or a two in and one out situation I work with small changes with the powder charge. I simply go up by .2 and down .2. .5 is too much and may change the velocity too much. If groups are over an inch that's when I,m going to fuss with the seating depth. If groups are two inches or more I,m likely to try a different powder rather shoot a box of bullets trying to chase it. That's my 2 cents worth on the subject.

 

[pharmseller]

So some of it maybe shooting magnum rifles with thin barrels and factory stocks? I understand it is harmonics, but when you shoot a few groups and they all look the same, you have to ask why did 2 bullets do this and not 1 or 3. I just don't get why it is always one.

Statistical variation. Ten shot groups won't have one out; it will produce a distinct pattern.

This.

Recover the target after each session and keep shooting at the same target. After time I believe you will see a group that does not have a distinct set of flyers, but rather a larger group than you might think.



P

 

[truck driver]

Maybe these two pictures will help. The bottom pic is the same target as the top and you can see the original group in the top picture at 12 o'clock, there are 18 shoots on that target and as I shot (all the same load same load and bullet ) I watched the shape of the group change or blossom some times it looked very ugly. This was done out of curiosity to see what would happen and how consistent the rifle and load was.

 

[RaySendero]

Can someone explain this phenomenon to me. It happens to me all the time. Sometimes it is the 2nd shot others it is the 3rd and in multiple guns. Why does it happen on a repeated basis and why doesn't the 1 out happen to group with the other 2 now and again?

wisconsinteacher, Can you post us pics of the targets?

 

[snoodcrusher]

Maybe these two pictures will help. The bottom pic is the same target as the top and you can see the original group in the top picture at 12 o'clock, there are 18 shoots on that target and as I shot (all the same load same load and bullet ) I watched the shape of the group change or blossom some times it looked very ugly. This was done out of curiosity to see what would happen and how consistent the rifle and load was.

Great illustration. Thanks for posting.


Sent from my iPhone using Tapatalk

 

[RaySendero]

Yeah, but those pics aren't from wisconsinteacher are they?
Did I miss something?

 

[truck driver]

Ray you didn't miss anything and they're my pictures I was using to illustrate the changes that can occur as you shoot more than a three shot group.

 

[RaySendero]

OK td - Got it.

I've got some thoughts on wt groups but would like to see them with the shots numbered in order.

 

[wisconsinteacher]

I have targets but I did not number the shot order and can honestly say I don't remember how they landed on paper. I will try to make my shots next time out and post a picture up for everyone to see.

 

[BretN]

My .280 M70 featherweight does/did this all the time. Two shots touching, one flyer an inch away. Sometimes the flyer was closer, sometimes further. Lots of load testing, different powders, bullets, swapping the stock for a B&C medalist, trying Sweet's 7.62 to make sure I'm getting all the copper out. It shoots better now, great actually. I've got two different loads I've settled on. One is about .75" consistently, and one I just developed shot under 1/2", which that gun hadn't done in years.

I've come to accept that with that pencil thin barrel, that's about as good as I'm going to get. The barrel and machining just aren't as good as my two Tikkas, so I shouldn't expect the same out of it. I'm happy with how it's shooting now, but it still killed deer just fine when all I could manage from it was 1.25" groups. Still, I won't buy another gun w/ a whispy barrel again. Premium barrels could be different, I don't know. Good luck with it. BN