Glock 21 session 2: Keyholing?

[szczescie]

Hi,

Is this keyholing? The holes are round, but the paper is tearing below the hole, and it was not doing this the last time.

Here are holes from early on:

http://s1376.photobucket.com/user/szczescie/media/1_zps41569e42.jpg.html

Here are holes about 100 rounds in...not seeing it here:

http://s1376.photobucket.com/user/szczescie/media/2_zpsc8e3cfdd.jpg.html

Here are the last holes of the day:

http://s1376.photobucket.com/user/szczescie/media/3_zps2d613a12.jpg.html

Ammo was .45 FMJ, 230 grain: PMC, Federal American Eagle, Winchester White Box, and Prvi Partizan PPU.

One difference is that today I was at an indoor range with a hanging target instead of an outdoor range with the target tacked against something firm. Sometimes the enthusiastic ventilation pulls the bottom of the targets back, putting the paper at a slight angle. This hasn't resulted in tears like this with my other guns (.22/.38), but I did see this:

http://www.calguns.net/calgunforum/archive/index.php/t-471591.html

"the target sways fore and aft and create a slanted surface that makes a slight keyhole when a bullet passes thru."

.45's are bigger and slower, so maybe paper tears differently with them?

An employee at the range said a barrel obstruction is causing the bullets to tumble, which doesn't sit right with me, but is disconcerting enough to get me to ask y'all. The barrel has spiral stripes of gunk, but it doesn't seem dirtier than other guns after a session of shooting.

Before today I only fired 200 rounds, and cleaned it that day with the plastic brush and rod from Glock until I didn't see any dirt in the barrel and patches were clean. I put a bore snake through it this morning.

Thanks...hopefully I'm just being paranoid.

[Oceanbob]

Looks fine to me. More than likely the target paper is just tearing. Cheap paper.

[Citadelgrad87]

There's no bore obstruction.

Glocks can be temperamental, did you note which ammo gave those results, or was it all?

My g 27 doesn't like Winchester white box and results in tumbling bullets. It's got less than 1000 rounds through it. Other ammo doesn't do that.

A guy told me that glocks are a bit finicky, not in cycling, but the timing favors some rounds. Never heard it before, but it explains tumbling in a basically new firearm.

[bwhited]

The darker section around the hole is what is important.
As long as it is round, you are ok.
Looks good from here.
The paper is just tearing.

[Bill Steele]

No key holing there.

[Sunday]

There is no keyholing going on .

[deerdeerdeer]

Keyhole would look like a key hole or the grain being vertica versus roundl. Awkward paper though!

[Condorguns]

Here you go OP. This is keyhole. Yours look ok.

[jayhuh]

Looks fine to me. More than likely the target paper is just tearing. Cheap paper.

^^^^^ This

[vliberatore]

My guess is that the paper wasn't hanging perfectly straight due to ventilationay the range (assuming indoor) and that's why it tore on the bottom.

[Click Boom]

Chill brah, glocks don't keyhole.

[deerdeerdeer]

Here you go OP. This is keyhole. Yours look ok.

I wonder if the Keyhole effect can cause more damage / expansion due to abnormalities or less due to instability. Has there been scientific study on this issue?