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+--- Thread: Tumbling? (/showthread.php?tid=887)
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Tumbling? - bwaites - 08-09-2011
This issue might be best somewhere else, but I can't figure out where else it really fits. Its a tech issue, but....
Saturday I was marking a target in the pits at 300 yards, when one of the shooters was having obvious difficulty getting on target, giving us dirt showers, then being 10 feet over the target. He finally got on paper, and this is what they looked like.
![[Image: 300winmag.jpg]](http://img135.imageshack.us/img135/1411/300winmag.jpg)
![[Image: 300winmag2.jpg]](http://img812.imageshack.us/img812/6571/300winmag2.jpg)
This was a 300 WinMag, shooting 180 grain projectiles. Factory Ammo, soft tip rounds.
They sounded strange, not the sharp crack you would expect from a 300 WinMag at 300yards, but more of a "buzz"
Rifle was new, with 50 rounds down the pipe. He was trying to get a zero for hunting, and decided to shoot a small competition at the same time.
Ideas?
Tumbling? - Hoot - 08-09-2011
If it's been like that for all 50 rounds, I'd be inspecting that crown under my stereo microscope.
Hoot
Tumbling? - JASmith - 08-09-2011
Normally one would see a partial or full profile of the bullet when it tumbles. These holes are decidedly irregular. Also one would normally expect that a 180 gr bullet from a .300 Win. Mag. wouldn't be going fast enough to come apart in the air.
Too bad he didn't have a box of a different brand/weight/style of bullet to go with the one he used that day.
Sounds like the best thing for him to do is the inspection suggested by Hoot, plus a good check of the bore for copper fouling. Then after those questions are resolved, return to the range with more than one brand of ammo.
Tumbling? - bwaites - 08-09-2011
I would have liked to see the crown, also. I can't imagine bullets coming apart at WinMag velocities, but it might explain why he had such a difficult time getting on target and why he hit the berm behind us so much.
The hole in the black was huge, I had to use 3 spotter stickers to cover it.
Tumbling? - JASmith - 08-09-2011
I've heard that a seriously fouled bore can do bad things to a bullet.
Tumbling? - bwaites - 08-09-2011
But in 50 rounds and all with factory ammo?
Tumbling? - JASmith - 08-09-2011
I have a .270 BLR that gets lots of copper when I use Speer TNT. Accuracy goes from 1.3 moa to 5-6 or worse if I don't clean it after 40-50 rounds. I run those bullets at aboiut 3200 instead of the 3400 I could get.
He might get badly fouled if he's got a rough bore and used something like the old all-copper bullets that have a big reputation for fouling the bore. Especially true if he tried a lighter, higher velocity, bullet for his first box.
Now, make no mistake, I wasn't there so can only speculate.
But, if you do see the gentleman again and the topic comes up he could probably make productive of a list of things to check and do.
Tumbling? - bwaites - 08-09-2011
The only thing he has shot are factory hunting loads. Cup and core bullets.
No solids.
Just seems a little wacky!
Tumbling? - JASmith - 08-09-2011
It will be interesting to see what caused his problem!
Tumbling? - warped - 08-09-2011
Does it have a muzzle device?
If so it could be shaving the jackets and then it flies unstable making that sound you described.
Something is causing instability, it could even be the crown or the bbl.
Tumbling? - bwaites - 08-09-2011
No muzzle device, lightweight hunting rifle. The guys next to him said that at about 10 shots he was pretty sore.
Tumbling? - Variable - 08-10-2011
That is definitely strange. I'd really like to see that rifle. I've seen some messed up Beowulf holes (amateurish smith did a rush job on an aftermarket brake and didn't open it up enough) that had some looking like that, but with a slick muzzle I'm stymied trying to puzzle out what would do that. As mentioned previously, I'd also expect to see some bullet profiles if they were just tumbling. Weird!!!
Tumbling? - stanc - 08-10-2011
Given the irregular shape of the holes, perhaps they are the result of the bullets hitting the ground in front of the target, becoming badly deformed and ricocheting into the paper?
It seems like that would also account for the "bumblebee" sound?
Tumbling? - leopard6.5 - 08-10-2011
Bill: Is it possible that when he thought he was on target he was actually skipping them into the target since he was so far off otherwise?
Just a thought.
Lee
Tumbling? - leopard6.5 - 08-10-2011
Okay Stan, so you can type faster than I can! LOL!
That was my first thought after wondering if he had a muzzle devise on.
Lee
Tumbling? - stanc - 08-10-2011
Lee -- Great minds, and all that, ya know?
Tumbling? - stanc - 08-10-2011
P.S. Maybe the holes in the targets aren't from bullets at all, but from rocks or other debris kicked up by the bullets as they grazed the ground in front of the targets?
Tumbling? - Variable - 08-10-2011
Ahh! Depending on topography and a few other things, you guys might be on to something. He might have been skip shooting it. That actually sounds pretty plausible depending on the range.
I know that during the assault courses out at Nellis-- I used to skip shoot the popups with the '60 all the time. It was a faster way to cheat and get them all down.
Tumbling? - JASmith - 08-10-2011
Duh!
...and his bench neighbors said he was sore after 10 rounds with a light barrel and heavy kicker.
Wonder if flinchitis was alive and well that day?
Tumbling? - JASmith - 08-10-2011
Variable Wrote:...I know that during the assault courses out at Nellis-- I used to skip shoot the popups with the '60 all the time. It was a faster way to cheat and get them all down.I did that accidentally to a rabbit with a .378 Weatherby Magnum in about '65 or '66. Funny, there wasn't a mark on the fur. I think the bits of sand got him!
Currently, I routinely try for the very bottom of impromptu targets -- folks only see them jump, so it doesn't matter whether it's the bullet, or dirt & rocks that did the final deed!