Help me Identify the cause of these marks on my bullet.

calvin5673

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So I've been reloading for a while, and have been noticing that small marks are showing up on my bullets if I chamber and extract them. It starts right at the ogive(or as near as I can tell) on the bullet, and causes a scrape about 1/10" long and continues for about 1/6" around the circumference of the bullet.

In order to help narrow down the cause, I used a hornady OAL guage in order to confirm that I had the correct OAL/Ogive (Typical method, insert several times, took the average and subtracted 3/100"s of an inch). I had another person check it as well. We sooted the bullets before inserting in order to see the marks more clearly. And sure enough they showed up, which eliminates extractor/feeding issues.

Now forcing the bullet into the the barrel then removing clearly shows the expected ring in the soot for the bullet contacts the lands, this additional rub mark ends at the ring and continues the aforementioned 1/10" toward the bullet tip.
The same mark shows up on all of the bullet types I've tried. (10 different bullets of varying brand and style)
The mark appears at the exact same spot on each bullet around the 3-4 o'clock position (when looking down the barrel from the chamber)
Mark doesn't seem to affect accuracy/precision.
Rounds need to be seated down to 2.26" OAL in order to ensure no mark (and seating that deep causes my precision to suffer)

Gun is a Savage M10 in .223.

I Have heavily cleaned the gun with no change.

I'm beginning to suspect that my chamber may have a small burr, or that one spot in the chamber is just less than the req'd diameter.




Sorry for the poor pic its hard to photograph something so small. I've tried outline the marks with an overlayed black line.

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Thanks, hope someone here can shed some light on my situation
 
new gun? can you inspect the chamber for burrs or tool marks?
if it's 3/4 oclock on a right handed chamber it could be extraction marks from the dragging back motion as the extractor may be an acting force on the round to eject it at that angle.
remove your extractor from the bolt face and try again with a new bullet (use a squid rod to gently eject the round... And don't use a live round...)
this will also tell you if the cartridge is at a high enough angle that when you push the bolt forward your not scraping the round into the chamber.
 
Perhaps I'm misunderstanding. it occurs on the bullets whether they are loaded into a cartridge or not. I.e. even when just dropping the pill straight in and then pushing out with a cleaning rod.
 
Drop a bullet in, push it with a stick, and it is going to funnel into the throat. It isn't going to fall into place perfectly coaxially aligned.
 
The pressure from the ejector pin puts a bit of side force on the loaded round, causing it to
contact the throat area on one side a bit more than the other. Not to worry, not an issue in
the real world.

Regards, Dave
 
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