Bullet tumbling

[djcantr]

I'm a new reloader. I went to the range today to test fire 100 rounds that I reloaded before I loaded any more. They're .45 ACP, 230 grain LRN bullets from J&K Bullets (sized to .452" with red lube), CCI primers, 4.8-4.9 grains of Winchester 231, seated to 1.250" OAL with a .4710-.4715" crimp. They were fired from a Kimber Ultra Carry II with a 3" barrel. All of the cartridges fed and functioned well in the gun. My aim still isn't the best and I'm working on that, but all rounds went where the sights were when the trigger broke. The two holes outside the center were the last two rounds fired. I don't know why, but it's like when I'm nearing the end of a magazine I start rushing to finish the mag even though I don't intend to. The loads seem as accurate as I am. Looking at the target, though, it appears as if they might be tumbling. There were seven rounds fired at that target. I've never had keyholes in targets with factory loads. Do you guys think the bullets are tumbling? Could it be I'm not getting the velocity of a factory round so they're tearing the paper instead of punching a clean hole? I don't have a chronograph to check these loads. If they are tumbling, what would I change in my load to correct it?



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[g.willikers]

Do a search, right here on this forum for "tumbling bullets" or "keyholing", or similar.
Others have had the problem, too.
There's many causes and discussions on the subject.

 

[Edward429451]

What distance did you fire them at? The charge seems a little light but not much. Perhaps the light charge and a short bbl is working against you.

Any bullets left? Weigh some and see how consistent the weights are. If they let a poor caster pour them they could be full of voids.

 

[djcantr]

I did search but all the threads I found were full of people asking the caliber, powder, charge weight, bullet sizing, bullet composition, etc so I figured each problem was quite specific and somebody might be able to advise on what's causing my problem based on the information I posted.

I did notice something interesting when I was cleaning my gun tonight. The barrel was dirty, but mainly on one side. One side was fairly clean and shiny and the other side was fouled. I don't mean the end closest to the chamber versus the muzzle. I mean running down the bore one side is cleaner than the other. What could cause that?

 

[djcantr]

I was at around 10 yards. Suggested charge is 4.3-5.3 grains, so I figured I better start at 4.8 or so since I have a short barrel. Bullets didn't have any voids. In fact, all weighed over 230 grains. I weighed about ten of them that were between 233 and 235.5 grains.

 

[Jim243]

I have only had that happen with Berry's Bullets in 9mm. As far as I can tell the bullets were badly made and undersized. Same problem keyholing at 15 feet. The bullet never got stablized. Try a different batch of bullets and see if this correct the problem.

Jim

 

[Jammer Six]

I had that exact problem in a government model with Berry's Bullets.

I switched the Hornady SWC and FMJ, and the problem went away.

I'll probably stay away from plated bullets, a real jacketed bullet seems to eliminate that problem in my guns.

 

[brokenarrow41]

I get the same results with under charged loads and nothing behind the paper.
They don't look like they're tumbling but going slow and ripping the paper. You should notice the difference with sound and recoil.

 

[serf 'rett]

That's some funky holes. While it may appear that the bullet is tumbling, the ripped paper "strips" has me scratching my head. I've seen some unusual holes when low grade paper is used. (Think in terms of "I'll save money by printing my own targets on this cheap copy paper.")

If you have more reloaded rounds, try shooting them at some card stock or cardboard. The thicker target media should let you see if the bullet is tumbling.

For me, the only Berrys bullet that tumbled was the one that glanced of the car hood during that IDPA comp a few months ago.

 

[overkill0084]

That's some funky holes. While it may appear that the bullet is tumbling, the ripped paper "strips" has me scratching my head. I've seen some unusual holes when low grade paper is used. (Think in terms of "I'll save money by printing my own targets on this cheap copy paper.")

If you have more reloaded rounds, try shooting them at some card stock or cardboard. The thicker target media should let you see if the bullet is tumbling.

+1
Try some paper plates. It's a cheap way to change it up and you will be able to judge it a bit better. All target paper is not created equally.
Slow moving LRN generally punch crappy holes anyway.

 

[m&p45acp10+1]

If you can go to an outdoor range try and put a board behind the target. If your rounds are tumbeling you should be able to tell easily. Sometimes the rip strips can happen on hanging paper targets at indoor ranges. Especialy if the fans are going over the target. I do not know exactly why, just know that it does. Round nosed bullets at low velocities can casue that rip as well.

 

[warningshot]

Just when you think you've seen it all. Dang!!!

Great responses too.

I've seen this with handguns but only at +50 yard and beyound stuff. Cool!

Try a box of 230 RN factory under the same conditions.

Please keep us posted. Dang! 10 yards? And the auto gun still functioned properly? Dang!

 

[will99]

bullet tumbling

DJ, I just had the same problem with 9mm using lead bullets. The puzzle was solved by seating the bullet as long as possible without actually jamming it into the rifling. Remember, this long bullet also has to feed from your mag, so test the first 5 or 6 cartridges in the mag and just thumb them out gently. They should all come out easily. Also use just a little more Win 231, not a self-defense load, but a good stiff one. That way there's no doubt that the bullet will obturate and fill the bore. I bet this clears up the problem. Understand, that if you have seated too deep, the bullet has to jump to reach the rifling. Hot gas passes the bullet at ignition and can take hot lead with it and prevent a good grip on the bullet. The more you shoot, the more lead builds up and the key holing gets even worse. If you shot a lot of rounds that key holed you no doubt had a mess of lead to clean out of the barrel. Get it all out or you will never find accuracy.

 

[djcantr]

I went back to the range yesterday and this time tried a cardboard target instead of paper. All perfect holes in the cardboard. Guess it was just an issue of hanging thin paper targets with no backer.

 

[Jimro]

Ok, what half of the barrel was clean, and which was dirty?

If it was the top side, then my guess is you have undersized bullets allowing gas to blow by as gravity pulls the bullet downward. If it wasn't the top side I don't have the foggiest.

The slow twist of the 45 caliber barrel doesn't make even a quarter turn in 3 inches, so it makes sense that only half the barrel would experience fouling if you used and undersized bullet.

Jimro

 

[243winxb]

LRN bullets

Round nose bullet do not cut clean holes. Semi-Wad cutters are better, but not perfect, because of the lower velocity of the 45 acp. I do not see any key holes.

 

[totaldla]

Put some cardboard behind that paper and your "tumbling" will go away.

 

[JASmith]

I'm not so sure that you are seeing tumbling because the profiles aren't quite right for tumbling round nose bullets of that weight -- the holes are too long for their width.

What is the quality of target paper you're using. Sometimes you'll get tearing of the paper with the very low velocities I think you've got. I get those tears when I use ordinary printer paper to make my targets (.38 Special, 40 S&W, .44 & .45). The hole quality improves when the printer paper gets smacked at higher velocities.

I still can't rule tumbling out at this point.

Many of the commercial lead bullets are very hard -- with the need to have near max pressures to get good obturation and eliminate the gas cutting. Per Hodgdon's web page (http://data.hodgdon.com/cartridge_load.asp), you can increase the pressure a bit more by going up by a few tenths of a grain. Increasing the pressure adds velocity and might improve the appearance of the holes.

If you try that or other corrective measures, pleas let us know waht worked and what didn't for you.

PS Totalda said it very succinctly while I typed this long-winded note!

 

[djcantr]

Ok, what half of the barrel was clean, and which was dirty?

If it was the top side, then my guess is you have undersized bullets allowing gas to blow by as gravity pulls the bullet downward. If it wasn't the top side I don't have the foggiest.

The slow twist of the 45 caliber barrel doesn't make even a quarter turn in 3 inches, so it makes sense that only half the barrel would experience fouling if you used and undersized bullet.

Jimro

Last time I went to the range the left side of the barrel was cleaner than the right side. Same thing happened this time. Sorry for the poor pics, but it's difficult to get decent pics while shining a flashlight in the other end of the barrel. I no longer have a digital camera after a burglary a few months ago.

This was a shot as I pulled it out of the pistol:

By djcantr at 2012-02-20

This was a shot after running a patch through it a couple times:

By djcantr at 2012-02-20

 

[djcantr]

I'm not so sure that you are seeing tumbling because the profiles aren't quite right for tumbling round nose bullets of that weight -- the holes are too long for their width.

What is the quality of target paper you're using. Sometimes you'll get tearing of the paper with the very low velocities I think you've got. I get those tears when I use ordinary printer paper to make my targets (.38 Special, 40 S&W, .44 & .45). The hole quality improves when the printer paper gets smacked at higher velocities.

I still can't rule tumbling out at this point.

Many of the commercial lead bullets are very hard -- with the need to have near max pressures to get good obturation and eliminate the gas cutting. Per Hodgdon's web page (http://data.hodgdon.com/cartridge_load.asp), you can increase the pressure a bit more by going up by a few tenths of a grain. Increasing the pressure adds velocity and might improve the appearance of the holes.

If you try that or other corrective measures, pleas let us know waht worked and what didn't for you.

PS Totalda said it very succinctly while I typed this long-winded note!

I decided they're not tumbling. I used a cardboard target and all of the holes were perfectly round. I did load 50 rounds to 5.2-5.3 grains (max published is 5.3 grains for the data book I looked in) and they shot much cleaner than the 4.9 grain loads. When I started shooting a shot a mag of factory ammo, a mag of 5.3 grain and 1.27" OAL, a mag of 4.9 grain 1.27" OAL, and a mag of 4.9 grain 1.25" OAL. The 4.9 grain loads were extremely dirty. I was even getting black flakes of I assume powder residue that was flying back on my arms as I was shooting. I think I'll just load 5.3 grain 1.27 OAL cartridges now.