Weird Comet Tails

The Accurate Reloading Forums

Weird Comet Tails

This topic can be found at:
https://forums.accuratereloading.com/eve/forums/a/tpc/f/6711043/m/5131018501

22 March 2009, 03:03

bartsche

Weird Comet Tails

While testing bullets every once in a while at 100 yds. I get perfectly round holes but powdery grey comet tails. The comet tail is not the jacket ripping through the target. It is easy to attribute this to lead tips vaporizing except it also happens with HP bullets.

Would kinda like throwing this open for discussion and see where it goes.

roger

Old age is a high price to pay for maturity!!! Some never pay and some pay and never reap the reward. Wisdom comes with age! Sometimes age comes alone..

22 March 2009, 03:49

Doc224/375

In a couple of nutshells Roger .

http://www.forensicscience.pl/pfs/59_waghmare.pdf

composition of impact residues.

http://arxiv.org/ftp/astro-ph/papers/0612/0612013.pdf

http://209.85.173.132/search?q...=us&client=firefox-a

A contact range gunshot entrance track with grey-black discoloration from the burned powder.

NOW IMO a possible explanation as to why an irregular trail may exist on a target .

Crown of the muzzle worn slightly ? Or is the bullet leaving more deposit on a particular side

or portion of the Bore , before exiting the muzzle . Thus leaving a " irregular print " pattern

in the target . I myself have pondered this very question on occasion .

My third and final explanation is space

22 March 2009, 03:57

vapodog

quote:
Weird Comet Tails

Occasianally I've seen this while prairie dog shooting (vaporizing)....and I admit....I don't know but I've always thought it was related to humidity in the air.....and yes....it seems to happen with hollow points as well as other soft points.....like a contrail from a jet airplane.

///////////////////////////////////////////////////////////////////////////
"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill

22 March 2009, 04:15

303Guy

Mmmm... I have mentioned before how I was lubing bullets and how they left a smoke trail all the way to the target. The sunlight was just in the right place to see it. Quite fun!

Nothing to do with the patterns on the target but it does illustrate that 'something' can follow a bullet a long ways.

Doc224/375, I cannot view the links - my PC doesn't work properly and the software to open the files is on another operating system. Damn!

22 March 2009, 06:24

redial

There's been some discussion about this here and at least one article in Precision Shooting magazine but it has mostly to do with the heated core escaping thru a void in the jacket.

Bullets get gawd-awful hot during their time in the barrel and some amounts of the core are compromised by melting or other means. If you have a pinhole in the bullet jacket or a small scar to let it out, that's what happens.

Bigger scars let the bullet disintegrate, more often if spun very quickly.

Mark

22 March 2009, 07:35

303Guy

quote:
Bullets get gawd-awful hot during their time in the barrel and some amounts of the core are compromised by melting or other means.

Now this is getting REAL interesting!
(I was thinking that a possible problem was bullet jacket heating in the barrel from friction, causing a looseness of the core but at the presures involed here, the core would fill the void anyway and go tight on temperature equalization. Mmmm... so many things to contemplate!)

22 March 2009, 09:52

armadillo

You didn't mention what cartridge or velocity you are using when this happens.

My only experience with this phemomenon was many years ago when Remington introduced "power loc" bullets I believe they were plated - not jacketed. I loaded some 80 gr. in a 6mm Rem and got comet tails on the ones that got to the target - some of them vaporized on the way. I figured they were doing 3400-3500 fps.

22 March 2009, 10:10

SR4759

I shot some soft point spitzers through a rifle at a 25 yard target when sighting in once. Each shot left a lead colored comet tail. I never have had this happen at 50 or 100 yards.

About bullets getting hot.
A friend of mine was a Marine in Korea during the Korean War. They were occasionally shooting from their hill top across at an adjacent hill top with their M-1s. They were being shot at by some thing like a M-91 Nagant.
One of the Chinese rifle bullets hit near them and stayed on top of the dirt. One of his buddies reached over and picked it up. It was hot enough to make him drop it with a howl.

22 March 2009, 22:17

bartsche

quote:
Originally posted by armadillo:
You didn't mention what cartridge or velocity you are using when this happens..

22-250, 52gr FBHP, oal=2.428", 3493 to 3530 fps., 3 shot 1/2" group @50yds., all comet tails. 2" group at 400 yds.

This is but one

Old age is a high price to pay for maturity!!! Some never pay and some pay and never reap the reward. Wisdom comes with age! Sometimes age comes alone..

22 March 2009, 22:36

tiggertate

Other than vaporizing lead in a 220 Swift, the only other time I made comet tails was when (in my youth) we cleaned a bunch of tarnished bullets in WD-40. I think there was enough residue in the HP to cause the smoke trail.

23 March 2009, 07:21

armadillo

quote:
Originally posted by bartsche:
2" group at 400 yds.

Great group. I wouldn't worry about it if it doesn't affect accuracy.

23 March 2009, 08:40

bartsche

quote:
Originally posted by armadillo:
quote:
Originally posted by bartsche:
2" group at 400 yds.

Great group. I wouldn't worry about it if it doesn't affect accuracy.

Not a worry just a thing of interest and disscussion.

roger

Old age is a high price to pay for maturity!!! Some never pay and some pay and never reap the reward. Wisdom comes with age! Sometimes age comes alone..

23 March 2009, 10:23

303Guy

May I suggest that the 'comet tails' are being cause by powder residue being drawn in the bullet turbulence trail. I have seen smoke trails with a 'puff' from a 303 Brit which was loaded with the old cardboard wad and bitumen seal. My own waxy-lube trail traveled a good 50m or more behind the bullet. I actually think it reached out passed 100m but that could have been sun glint on the bullet. That bullet was a lot slower, being a 303 Brit with mild loads.

23 March 2009, 13:55

seafire2

cutting their way thru the LA/ So Cal smog?

Life Member: The American Vast Right Wing Conspiracy

Jan 20, 2009.. Prisoner in Dumocrat 'Occupied America', Partisan in the 'Save America' Underground

Beavis..... James Beavis..... Of Her Majesty's Secret Service..... Spell Check Division

"Posterity â€” you will never know how much it has cost my generation to preserve your freedom. I hope you will make good use of it."
John Quincy Adams

A reporter did a human-interest piece on the Texas Rangers. The reporter recognized the Colt Model 1911 the Ranger was carrying and asked him "Why do you carry a 45?" The Ranger responded, "Because they don't make a 46."

Duhboy....Nuttier than Squirrel Poop...

24 March 2009, 05:25

lngshtr1

I HAD THIS VERY THING HAPPEN TO ME YEARS AGO WITH A REBARREL FROM SHAW. COME TO FIND OUT THE BARREL HAD A TIGHT SPOT AND WAS CREATING VERY HIGH PRESSURE ALONG WITH VERY HIGH VELOCITY. THE BULLETS WERE GETTING SO HOT THAT THEY COULD BE SEEN ALL THE WAY TO THE TARGET IN A GRAY HAZE.SOME OF THE BULLETS NEVER MADE IT TO THE 100YD TARGET.I WOULD SAY THAT WHATEVER YOU ARE EXPERIENCING MOST LIKELY HAS SOMETHING TO DO WITH VELOCITY AND BULLET SELECTION.NOT TO BE CONFUSED WITH HIGH HUMIDITY VAPOR TRAILS !

25 March 2009, 07:04

ALF

25 March 2009, 20:03

bartsche

quote:
Originally posted by ALF:
Vapour Trails ( not powder residue or "molten lead") Residue travels only a short distance.

The mechanism is due to the flow of humid air around the bullet ( fluid mechanics), the boundry layer pressure drops and this leads to condensation that then shows up as a vapour trail but only under certain ambient conditions. It is most apparent in small caliber high velocity cartridges. Most reports are from high velocity 22's

Alf, I can buy into what you're saying similar to the moist air visually compressing around a super sonic airplanes body and wings, but where does the gray coloring come from?

roger

Old age is a high price to pay for maturity!!! Some never pay and some pay and never reap the reward. Wisdom comes with age! Sometimes age comes alone..

25 March 2009, 20:08

tiggertate

quote:
Originally posted by bartsche:

but where does the gray coloring come from? roger

How old are the bullets?

26 March 2009, 01:45

DEC

A buddy of mine and I hunt groundhogs and usually video tape the hunts. On every occasion when I'm zoomed in on the groundhog and the bullet enters the picture you can see the vapor trail. It slow mo it's really neat!

26 March 2009, 04:52

bartsche

quote:
Originally posted by tiggertate:
quote:
Originally posted by bartsche:

but where does the gray coloring come from? roger

How old are the bullets?

Of course I have no idea but they are rather bright and shinny.

roger

Old age is a high price to pay for maturity!!! Some never pay and some pay and never reap the reward. Wisdom comes with age! Sometimes age comes alone..

26 March 2009, 05:35

Bent Fossdal

If you are shooting in the dark, al trails are grey.......

Sorry, what time is it and who tossed away that cap on my whisky jar?

26 March 2009, 10:38

303Guy

quote:
Originally posted by Bent Fossdal:
If you are shooting in the dark, al trails are grey.......
Sorry, what time is it and who tossed away that cap on my whisky jar?

That was clever!

26 March 2009, 10:41

303Guy

quote:
Originally posted by tiggertate:
quote:
Originally posted by bartsche:

but where does the gray coloring come from? roger

How old are the bullets?

Well you know, occasionally age produces a slight gingery colouring - don't ask me why but I do get accused of using bleach!

26 March 2009, 21:43

tiggertate

quote:
Originally posted by bartsche:
quote:
Originally posted by tiggertate:
quote:
Originally posted by bartsche:

but where does the gray coloring come from? roger

How old are the bullets?

Of course I have no idea but they are rather bright and shinny. roger

Just a bad joke, Roger.