Tumbling?

[bwaites]

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.

http://img135.imageshack.us/img135/1411/300winmag.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?

[Hoot]

If it's been like that for all 50 rounds, I'd be inspecting that crown under my stereo microscope.

Hoot

[JASmith]

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.

[bwaites]

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.

[JASmith]

I've heard that a seriously fouled bore can do bad things to a bullet.

[bwaites]

But in 50 rounds and all with factory ammo?

[JASmith]

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.

[bwaites]

The only thing he has shot are factory hunting loads. Cup and core bullets.

No solids.

Just seems a little wacky!

[JASmith]

It will be interesting to see what caused his problem!

[warped]

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.

[bwaites]

No muzzle device, lightweight hunting rifle. The guys next to him said that at about 10 shots he was pretty sore.

[Variable]

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!!!

[stanc]

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?

[leopard6.5]

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

[leopard6.5]

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

[Variable]

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.

[JASmith]

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?

[JASmith]

...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!

[bwaites]

Skip shooting is plausible. We didn't get a dirt shower with the shots that are pictured, but if he hit far enough in front of the berm we wouldn't have and it is hardpan/gravel a little farther out.

That makes more sense than anything I've been able to figure out!

[pappy42]

If I was the feller in question; I'd pay Mr. Waites to shoot 5 shots and see what the results looked like.

[bwaites]

If I was the feller in question; I'd pay Mr. Waites to shoot 5 shots and see what the results looked like.

Lol! I sight in or help people sight in rifles all the time, just to see their faces when they start hitting targets at 400 yards or more!!! No payment required! But a light weight 300 WinMag wouldn't be my first choice!! Ouch!!

[pappy42]

Lol! I sight in or help people sight in rifles all the time, just to see their faces when they start hitting targets at 400 yards or more!!! No payment required! But a light weight 300 WinMag wouldn't be my first choice!! Ouch!!

Yep, I've got one. Cooked up some hot 200 grain loads for African plains game and the bench sighting sessions were no fun. At my age and shooting style; the dang thing jumped out of my hands each shot.

Funny; the jumping out of hands thing didn't happen when shooting game.

[bwaites]

Yep, I've got one. Cooked up some hot 200 grain loads for African plains game and the bench sighting sessions were no fun. At my age and shooting style; the dang thing jumped out of my hands each shot.

Funny; the jumping out of hands thing didn't happen when shooting game.

That adrenalin is amazing stuff, isn't it!! LOL:)

[Variable]

Yep, I've got one. Cooked up some hot 200 grain loads for African plains game and the bench sighting sessions were no fun. At my age and shooting style; the dang thing jumped out of my hands each shot.

Funny; the jumping out of hands thing didn't happen when shooting game.
Five word solution (if they were skipshots...): Caldwell Lead Sled & Muzzle break.... :D

[warped]

Al, just send me the bbl and I will thread and install the brake.

Gimme a call if you want...

[Jaywalker]

I think they were tumbling. If tumbling, they don't always show the full profile, because like a spun knife, sometimes they almost hit the point and you don't get the profile.



When Charter Arms was making a five-shot 44 special revolver, the Bulldog, they had trouble with tumbling. Back when the American Rifleman was worth a damn the NRA tech staff tracked it to a barrel constriction at the frame connection point. Perhaps the throat was reamed improperly, or the bullets were undersize and didn't take the rifling. Sometime rifles just don't like a particular bullet, and maybe some version of this rifle's problem is the reason. I'd love to see the rifle and mike the bullets.