Maybe it's powder residue. It stands to reason that some of the gasses get past the bullet in the barrel, maybe some of them stick. Anybody have access to FTIR?
Posts: 196 | Location: MN, USA | Registered: 03 March 2002
It might even be lead from the nose of the bullet! I have seen a spiral, pinwheel print around bullet holes from bullets that were melting like using bullets for the .222 Remington at over 3500 fps.
Also I agree that it may be dirt in the barrel from powder residue. I shot a group with a rifle that had been cleaned really well and the holes looked clean. Later shooting showed the holes to be dirty. Also the groups opened up also. But I admit I am having trouble with this rifle.
my theory is that the paper is somewhat burned from the bullet "drilling" it way through the paper. I believe that a 30 caliber bullet with a MV of 2900 fps is spinning at about 30,000 RPM
Any mathematicians out there?
------------------ Don't tread on me! Pennsylvania Frank
Posts: 1984 | Location: The Three Lower Counties (Delaware USA) | Registered: 13 September 2001
It's the same thing as running a patch down the bore. The patch comes out grayish black. Well them, so does the bullet. Bore fouling transfers from the bullet to the paper. What's so hard about that. I'm sure this is something we all really need to know. Yeah, yeah, I know, don't be a smart ass.
------------------ there's a fine line between hobby and mental illnes
Posts: 8169 | Location: humboldt | Registered: 10 April 2002
Yes, I believe it is barrel fouling. A few years ago, I heard about a guy who showed up to a BR match with bullets coated in a white substance...His bullets holes did not exhibit the trademark black ring. Some people were concerned that the scorer wouldn't be able to measure them properly...
Posts: 160 | Location: Southern California | Registered: 28 September 2000
quote:Originally posted by craigster: It's the same thing as running a patch down the bore. The patch comes out grayish black. Well them, so does the bullet. Bore fouling transfers from the bullet to the paper. What's so hard about that. I'm sure this is something we all really need to know. Yeah, yeah, I know, don't be a smart ass.
Craig,
I believe you are right. I figured it was either powder fouling or copper rubbing off on the paper. One thing is sure, the gray bullet holes from 180 gr. Sierra ProHunters do not turn green or blue with copper solvent. I am inclined to believe it is powder fouling and not copper.
H. C.
Posts: 3691 | Location: West Virginia | Registered: 23 May 2001
Posts: 8351 | Location: Jennings Louisiana, Arkansas by way of Alabama by way of South Carloina by way of County Antrim Irland by way of Lanarkshire Scotland. | Registered: 02 November 2001
quote:The paper around the hole being gray regardless of the bullet being lead, JHP, FMJ, whatever, was perplexing to me and one poster.
There is only one thing that's a constant amongst the stated conditions� all bullets leave a grey ring.
Conventional ammunition requires the burning of powder to get downrange. That fouling is the only thing the bullet touches in it's trip down the bore, any grey trace on the target, can ONLY be from powder residue.
It is simply a combination of jacket material and powder fouling. These particles are microscopic in size and are primarily powder fouling hence the gry color. Some BR shooters will color their bullets with black Mgic Marker to make the bullet holes more visible in bad mirage conditions. I have noticed the bullet hole being decidedly blacker when I'm using ball powders. Regards, Bill.