Bad bullet? Weird flyer at 600 yards

[coloradokevin]

I want to diagnose a problem I had shooting precision rifle today with a familiar hand load. We've all missed shots due to wind calls, etc. But, I've never missed a shot by this margin before, especially when I KNOW I broke the shot clean.

I often shoot steel plates to 500-600 yards, which is the maximum distance available at my range. Today I was shooting and had one HUGE unexplainable miss on a 600 yard plate. After shooting a 1.5" group of 4 consecutive shots on the 500 yard plate, and two consecutive hits on the 600 yard plate, I watched a third shot at 600 miss the 12" plate by at least 5 mils (that translates to 9 feet or so at that distance).

I've been shooting this load for 3 years with good accuracy and no problems. Even at the 600 yard line I can't think of ever having missed by more than 1 Mil on verified dope. The only recent change to the dope was a brass change, which seems to have increased my velocity a bit, but has still provided good accuracy.

So, what would explain a flyer that misses by such an impressive margin?


Also: The trigger release was good, I'm using a S&B scope, 175grain .308 SMK bullets, and I was able to observe the miss through my scope (as was my spotter through his). We both agreed it was a 5 mil miss.

 

[allaroundhunter]

Did the shot feel normal (i.e. recoil, sound)?

Was the elevation good, just a windage miss?

 

[coloradokevin]

Yes, just a windage miss. Elevation looked good. Shot felt normal. Shot broke clean (I watched the impact through my scope). The brass looked normal in examining it after the shot.

The wind was moving left-to-right at a variable 5-10mph, 3/4 to full value. I was holding 0.7 mils left on my reticle at the time, which had been yielding hits on the other shots. I broke this shot, and then watched it hit pretty much on my 5 mil windage dot in the reticle (5 mils left).

Also, we can rule out reticle cant. My scope is in a Spuhr mount with a built in bubble level, and the reticle was leveled before taking the shot.

 

[allaroundhunter]

Jeez....

This one has me stumped. I suppose it could be a bad bullet with internal construction flaws, but it is hard to say for sure... More likely could have been a slight barrel obstruction; something extra left behind from the previous shot.

Did rounds after that fire accurately?

 

[coloradokevin]

Yeah, next shots did what they were supposed to for the most part, though I was down to my last three rounds when the problem occurred. I missed by probably 0.1 mil on the next shot (a more expected miss with the changing winds), and then I corrected my wind hold and nailed the final shot.

But, believe me, this one had me stumped, too. My initial thought was that the scope was probably loose, but it looks to be tight (and is in one heck of a beefy mount, if you're familiar with Spuhr mounts). So, by process of elimination I'm leaning toward believing it was a bullet issue, or perhaps the obstruction you suggested.

 

[FROGO207]

I am also thinking bullet problem. But it might have been a dropout in the wind as it was sideways error. You probably did not weigh the bullets either did you? Sometimes there is just something that happens and you will never know why. Bullet hitting a small bit of flying debris shortly after leaving the barrel is a thought also but you would have seen it I am assuming.

 

[MtnCreek]

I would mark that brass to see how it does next time. If it shoots good next go around and no other issues with other bullets, I would chalk it up to whatever and move on. When I first read it, I thought it was a bad powder throw, but that would have put you low. Strange things happen at that distance, but 5mils is a lot.

 

[KeithET]

Bullet hitting a small bit of flying debris shortly after leaving the barrel

What are the odds that it hit a bug somewhere in mid flight? Will never know but just had to add that for grins!

KeithET

 

[Trent]

I hit a bird in flight once with a 22-250. It was frigging spectacular. Nothing but bits of down and feathers out at 125 yards.

Unless it happens again, chock it up to a bad bullet.

 

[hueyville]

Write it off unless it occurs again. Was this final shot of day or did subsequent rounds continue to perform to standard?

 

[savanahsdad]

I hit a bird in flight once with a 22-250. It was frigging spectacular. Nothing but bits of down and feathers out at 125 yards.

Unless it happens again, chock it up to a bad bullet.

I had a guy tell me he missed a nice buck because a bird flew in the bullets path , he said it was a nice broad side shoot , no way he could miss , then , bang , and the deer ran off , he then said he saw feathers floating down to the ground ? maybe BS?, but it could happen , or a bug , or maybe some ice falling from a tree branch ?? , alot of things could happen in 600 yards , , I wouldn't lose any sleep over it ,

 

[Trent]

I had a guy tell me he missed a nice buck because a bird flew in the bullets path , he said it was a nice broad side shoot , no way he could miss , then , bang , and the deer ran off , he then said he saw feathers floating down to the ground ? maybe BS?, but it could happen , or a bug , or maybe some ice falling from a tree branch ?? , alot of things could happen in 600 yards , , I wouldn't lose any sleep over it ,

If I hadn't seen it with my own two eyes I would have never believed it. My son (who was 5 at the time), was with me, and thought it was the coolest thing he'd ever seen. So did I.

This was a public range I used to go to, around harvest time some guy had brought out fruits to shoot at, pumpkins and stuff. So the range was littered with seeds and husks and stuff, birds were all over.

So I had a better than average chance of intercepting one, I guess.

I certainly don't expect it to happen again in my lifetime. I keep waiting for a deer to run out between me and the target but it hasn't happened yet.

 

[Slamfire]

Bad bullets happen, even in match bullets.

A bud of mine who is an outstanding High Power shooter told me he weighs all of his Sierra Matchkings. He has found light bullets, like 150 grain in 168 containers, which he said light lead cores caused the weight differences. If he says he has seen this, then it exists. I am too lazy to weigh my bullets.

People who own Verne Juenke machines have posted their experiences between bullet brands. This is one post:
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2110800

I found this article interesting: http://www.24hourcampfire.com/reloading.html
A center of gravity in line with the axis of rotation is critical to accurate shooting. If the jacket thickness varies, if the core is uneven, if the CG of the round is not where is should be, the bullet could go anywhere.

 

[c.latrans]

Was this a horizontal miss? Without being there, and not knowing the layout of your range, I have seen hits just graze the plate and then throw up dirt several mills away on the backstop. Any chance of that?

 

[rooster59]

My guess as posted by Slamfire, "A center of gravity in line with the axis of rotation is critical to accurate shooting". Goofy bullet jacket = goofy bullet and you may not see a big difference with a scale. CF not = CG. Your bullet spun about 1800 times before it hit.

 

[coloradokevin]

Was this a horizontal miss? Without being there, and not knowing the layout of your range, I have seen hits just graze the plate and then throw up dirt several mills away on the backstop. Any chance of that?

This seems to be the leading theory on another site I posted this question on. My buddy owns the plates we were shooting, and said that there was a slight sign of a grazing shot on the edge of the plate.

I do know that the plate didn't move any perceptible amount on this shot, for whatever that's worth.

 

[c.latrans]

For what its worth, If you are able to examine that plate closely, I bet you have found your answer. Years ago shooting Metallic Sils. I glanced one off of a rams butt just like that and saw the shot throw up clods a good 20 feet behind the rams posterior on a dirt backstop maybe 20 yards behind the target. None of the watchers heard so much as a "ping"....some of them even thought I had shot at the wrong bank of targets. Have seen it happen on gongs/plates too, without hearing the hit. But who knows, funny things happen sometimes when a shot goes.