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Barrel Rifling

3637 Views 24 Replies 10 Participants Last post by  little_scrapper
Found something odd the other day.
Me and a buddy were out at the lake doing some plinking and we set up a few water melons. I unfortunately forgot to pack the hollow points so I had to use my standard FMJ target rounds which of course was very anticlimactic and just punched holes in em.
Behind our target range is a large hill that consists mainly of sandy soil this being in East Texas,and while checking out the less than stellar damage to the melon I found a slug that was totally complete with almost no malformation to it. In fact checking it with a micrometer showed no damage to the circumference and it varied from .440 to .448 depending on whether you were checking across a land area left by the rifling or not but it is consistent all the way around the slug.
And here's the odd part....there are six land areas on the rifling of a FNX .45 barrel but it it only left 5 grooves on the slug. The 5 grooves are evenly spaced and than there's a gap between one and five where the 6 groove should be.
Looking through the barrel everything looks just fine and you can easily see all 6 land areas,yet one didnt transfer to the slug.:evil:

I guess I'm going to have to put some rounds into a water tank and see if I can recreate my findings.

Any thoughts?
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Are you absolutely sure this was your bullet? Nobody else shoots this location?
There's no doubt it's mine. Me and my buddy put up all the steel targets and target frames and it's on private property.
This thread is worthless without pictures
I suck at the internets but I'll see what I can do.
Are you absolutely sure this was your bullet? Nobody else shoots this location?
I guess I should add that the slug fits like a puzzle piece in to the end of the barrel. In other words it's a perfect fit.
After hitting the slug with scotch bright to try and bring out some contrast for a photo you can faintly see the missing rifling imprint though it's not complete like the other five.
I'm going to chalk it up to cheap white box ammo until I can put a few rounds of different ammo into a water drum.
Possibly just an undersized bullet.

I've found many bullets while at a sand pit that I shoot at. Some of them were probably mine (plated flat nose bullets), other FMJ's, no idea. It's private property, but other people have permission to shoot there.
I have to agree. Three or four thousands would make a noticeable difference in the depth of the rifling marks.
bullet could be out of round as well. between the rifling, possibly out of round bullet, etc. you might just not get much rifling marks on that side.

rifling marks are like fingerprints, every barrel will make different marks on the bullets.
Yeah..now i'm just curious as to the cause.
Most likely a flaw in the slug though. Highly unlikely the rifling would be off that much.
SWAG but the bullet may have been flattened a bit at the factory before being loaded. Bullet makers don't always give their products a lot of TLC and WWB is loaded with quantity in mind unlike match ammunition. May have gotten by QC. Unless more of your bullets show up missing a groove, I wouldn't fret over it. Likely just a bad bullet. As luck would have it you just picked this bullet to examine.
Thats my guess. Of course now I'm going to have to go through the hassle of filling a barrel with water just to ease my mind.
The difference in diameter is in the thousands which would be enough to see the difference.
Am I the only one not seeing pictures?
Hope not. If it appears to be a problem someone let me know.
Nope. I'm not seeing anything either.
Now thats weird.
Can anyone besides myself see them?
Just checked with my phone and no pics. Like I said,I suck at the internets.
You ain't missing much,just a slug with one piss poor rifling mark.
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