What causes flyers

[12many]

I was shooting some bolt action rifles this weekend and about 50 yards to sight them in an work up some ballistic tables to keep with the rifles. Ok, mostly for fun.

The groups were good, most of the time. It was only 50 yards with a CZ 223 and a Savage HMR 17 both bull/varmint barrels, shooting from a rest. So often touching holes or very close but maybe every 10th shot hit an inch or so off the rest of the group. I can still see through the scope when the round goes off and I swear it is right on target, so I don't understand why it is so far off. Some you can tell you pulled the trigger too soon or were off, but most looked good.

Is it the shooter and I am seeing things, or is it the ammo, or the rifle? I was using was mid range stuff (Fiocchi 223 vmax 40 grn in a 1:12 twist barrel and 17 grn Hornady HMR). I know it could be me, but many looked good through the scope. The ammo is not perfect so maybe that is it or the rifle needs cleaning. Usually the groups are tight so it seems random.

Anyone have any thoughts on this? We always hear "it was a flyer" but what's the cause?

Thanks.

 

[MyRoad]

I've often had a similar experience, but in smaller batches -- If I shoot a five round group it seems that pretty consistently 4 rounds will be tight, and one will be twice as far from the group as the others are to each other (if that makes any sense, i.e., one flyer in every five).

I've always attributed it to "operator error", or more specifically me momentarily losing my concentration/focus, or possibly flinching slightly -- it doesn't take much to move a bullet an inch or two off of its intended path.

I'll relate a story (read this online, don't recall where…), in case it helps: A guy was wondering what makes Russian ammo less accurate, so he did some testing. One thing was to remove the bullets from the casings and measure the powder. He found that the powder varied widely. He remixed it and reloaded them evenly, and found the group sizes to be half of what they were with an off-the-shelf box. His conclusion is that Russian ammo is less accurate because during manufacture their powder is allocated inconsistently.

Relevance: It's possible that any factory ammo is susceptible to inconsistencies, and that something like every 10th (+/-) round having more or less powder, could throw that rounds POI off. Just a thought.

 

[tuj]

Flyers usually are the result of variations in velocity which is due to variations in the powder charge in the case. This is why hand-loading can produce superior results to factory loads. A chronograph can give you indications if this is happening.

Except in the case of the 17hmr, we are stuck with what CCI gives us, which they claim is already 'match grade'. I would agree that the current 17hmr ammos aside from Winchester (which makes their own, all the rest are rebranded CCI) is pretty good, it's not as good as very high quality 22lr ammo like Eley Tenex.

 

[MachIVshooter]

Usually the shooter, but sometimes a flaw in the bullet or load. Can also just be the random "perfect storm" of variables, none of which are particularly detrimental to accuracy on their own, but combined, they throw the shot.

A flyer is not, however, the widest shot in each group. "Best 4 of 5" isn't how we calculate; a true flyer is one that lands way outside of the group, and is clearly the result of an error or flaw.

 

[Sunray]

"...The ammo is not perfect..." Exactly, but neither is the trigger/shooting bench interface. It doesn't take much of a wee twitch to throw a shot off. Half a breath at the wrong instant, an itch, etc. However, a tiny breath of wind, slightly misloaded cartridge or flaw in the bullet will do it too.

 

[taliv]

it depends on how you define flyer

to me, a flyer is a shot that is off call. reasonably experienced shooters get pretty good at calling their shots. when they're sure one didn't go where they thought it should have, then i'd call it a flyer. if it happens once in a while, i'd blame the ammo. if it starts happening pretty frequently and you have a lot of rounds on the barrel, i'd say your barrel is shot out, especially if you've seen a loss of velocity too.

if it's always shot number 4 or 5 in a 5 shot group, that's mental. not a flyer in my book, and not the fault of the gun/ammo.

since the OP is kind of acknowledging this, i'd say potential causes are inconsistent position that could result in barrel/action/stock interface changes (normally resolved by proper bedding) or at that distance, parallax can be a pretty big issue. also, pushing the trigger to the side, or jumping off the trigger can do it. have someone video you while you shoot and then watch it and see if you can tell a difference.

 

[Arkansas Paul]

Can the barell heating up after several shots in a row cause a flyer?
Or will that just cause them to string?

 

[taliv]

it can cause a different POI, sure, but it would affect all the shots fired when heated, not just one in a string. i.e. if you fire 5 shots in 1 min and the 5th one is an inch out and the other 4 are touching, it wasn't barrel heat.

 

[carbine85]

Lots of variables here. Assuming you are doing your part it's usually the barrel or ammo. The type of rifle you are using (long thin barrel) usually loose accuracy after a few rounds.
I attribute most of my flyers to triggers or ammo.

 

[12many]

Interesting. Thanks for everyone's replies. I am going to try a more stable rest next time.

I take credit for many of the flyers, but some just seem like the perfect release and my jaw drops when I see it off by an inch or at 50 yards shooting.

 

[Art Eatman]

To my personal knowledge, the question has never had a definitive answer since at least 1950.

Having read The American Rifleman since the 1940s issues, you can go back even further.

Listen to folks' reasons. Then, after all have had their say, just figure "All of the above."

 

[Cee Zee]

There are actually many answers why they can happen. Common issues are bad ammo (there are probably dozens of issues under this banner alone like the bullet not seated properly - too much powder - too little powder - bullet out of round - etc.), barrels touching the stock in a different way than normal (like after they heat up too much), a bad crown, a barrel that needs to be cleaned, a barrel that has been cleaned too much (depending on the type of ammo and caliber with .22 being the worst for this), an inconsistent strike of the firing pin, an inconsistent loading of the cartridge in the chamber, holding your tongue wrong, the sun got in your eye, etc. etc. etc..

The whole trick to being a really good shooter is learning to track down the issues. Lots of issues can be conquered by picking the right equipment. Your rifles sound very good but the ammo you chose for the .223 is not exactly the best. People reload for a reason. And .17 ammo is not exactly the epitome of consistency. In fact it's well known to not be consistent.

If you shoot enough chances are you can learn when you messed up the trigger pull or whatever. But you can see bullets flying erratically too. I've seen .22 ammo do some real strange stuff and I suspect the .17 ammo we can buy is pretty much in the same boat. You have very little control over the ammo for a .17 which is a big reason I dont' buy one. But they have their uses and generally they shoot well. Just not always.

There are charts and help guides etc. that might help you figure out the problem but I'd bet a dollar to a doughnut that it's the ammo this time. Being off an inch at 50 yards for a good .223 is pretty bad. It would be hard to yank the trigger that much or even flinch that much. A .223 doesn't generally cause a lot of flinching issues because it isn't that loud and it doesn't kick much.

I'd be happy with what you have. For the .223 I'd try some different (better) ammo like maybe some Black Hills stuff. That should help but remember that off the shelf ammo is subject to production issues just like .22 ammo is. The batch number on each box will tell you something if you have consistently good or consistently bad groups with that box. The lot does make a difference. Again that's why people roll their own. With the .17 there really isn't a lot you can do about the ammo issues. You pretty much have to accept that you will get some flyers. That's just how it is. The best fix for that rifle is to replace it with a rifle where you can roll your own unfortunately. It will shoot pretty darn good the way it is but it will never have those great groups all the time because of the ammo issue.

 

[Walkalong]

Most "fliers" are just bad shots when the load and equipment aren't at fault.

Fliers do happen of course, but not often when using top class equipment and bullets properly loaded.

 

[utvolsfan77]

12many, does it happen with each group or only the first group fired during each range session? If it is the latter, often times it can be a cold bore shot that appears as a "flyer". The barrel warms up and then the next four shots group. I experienced this a couple of years ago with a Savage 16 with a 26" bull barrel chambered in .22-250. It only happened with a cold bore and only with factory ammo. Once I started reloading, the problem largely seemed to resolve itself.

 

[C0untZer0]

The same reason very very few people can bowl 300

 

[il.bill]

The same reason very very few people can bowl 300

^ This is an apt explanation for one out of five shots being one inch away from the other four touching.

 

[Walkalong]

Very true.

 

[denton]

Of course, it can be any number of things, including non-concentric jacketed bullets. In that case, the bullet spins around its geometric center in the barrel, and shifts to spinning around its center of mass when it exits. That does cause a flyer. I've got a batch of cheap foreign bullets that seems to have that problem.

There is one other cause that is less well known. It's covered in Harold Vaughn's book, Rifle Accuracy Facts.

It turns out that with standard threads, its is very difficult to make a truly rigid junction between barrel and receiver. Just a couple of the threads end up bearing practically all the stress. There is an alternate design thread that Vaughn recommends. He says changing to that type of thread cleared up a persistent flyer problem with one of his rifles.

 

[Reloadron]

You may want to give this thread a read. There was also a handgun thread of the same era.

In general any number of things but I generally attribute my flyers to none other than the shooter. I shoot a sub 0.4" group (5 shots) with my 308 bolt gun, all over the chronograph and all with weighed bullets, brass and powder. What should all be really good hand loaded ammunition. Then I shoot a group with a flyer an inch out from the other four shots. All 5 shots chronograph just fine. The next group was again like the first so that sort of points to me.

Ron

 

[tuj]

And .17 ammo is not exactly the epitome of consistency. In fact it's well known to not be consistent.

Nah. Varmint Al got a 35fps sd on a 2650 fps round. Its pretty consistent stuff.

I suspect the .17 ammo we can buy is pretty much in the same boat.

You are correct. All the 17hmr ammo is made by CCI with the exception of Winchester, which is notoriously bad and known for case neck splits.

 

[taliv]

i wouldn't even practice with 35 fps SD ammo. that's awful!

 

[denton]

i wouldn't even practice with 35 fps SD ammo. that's awful!

Most of the commercial rifle ammo of various sorts that I have tested over the years comes in at around a 35 FPS SD.

 

[12many]

What is average standard deviation of good handloads?

Wouldn't this deviation only affect elevation error, and not right to left error?

This thread has me really itching to go out shooting again.

 

[denton]

Typical handloads are hard to characterize. Some people are a lot more careful in their handloading than others. Neck tension, bullet weight, and case capacity all matter.

A long time ago, I wondered what I could do with 223 loads. With just modest effort, I was down to the low 20s. With more care, I was consistently into single digits. None of that made any difference at all. The rifle still consistently printed 5/8" five-shot groups.

Normal variation in powder charges make a negligible contribution to muzzle velocity variation. That's because of the non-linear way variation adds. If your powder measure has an SD of .1 grain, you'll be a long time shooting enough rounds to detect its contribution to MV variation.

 

[BCRider]

What are you using as a rest for the rifles?

I ask because a local buddy found the same thing happening. It turned out that the bipod he was using would stick on something rough on the bench on occasion and kick the gun up on one leg. After he put a slippery mat down to rest the legs on this went away. He's since removed the bipods and gone with a good bag rest.