Keyholing first 2 rounds

[Apple a Day]

Okay, this made me scratch my head:
The other day I was at the range. I had taken my brother the Friday before, cleaned the guns, and gone again a few days later. One thing I noticed with two revolvers that I had just cleaned was that the first two rounds our of each of them wandered WAY off target [a couple of inches at 25ft] and keyholed a chunk out of the paper. One was a .22 and the other a .357 magnum. After the first two rounds they tightened up and shot fine.
Now I am SURE I swabbed out the barrels before I went to make sure that there was no oil or anything left in the barrel. I was down to the last little bit out of the bottle of Hoppes when I cleaned them. #9 backwash? or did I just not do a thorough enough job swabbing out the barrels? The other handguns did fine.

 

[blades67]

Could've been a couple of undersized lead bullets.

 

[boing]

Momentary swarm of locusts?

 

[Blackhawk]

The other handguns did fine.

Just curious as to whether or not you cleaned them beforehand the same way? Secondly, were the other guns all firing subsonic rounds?

Hoppes #9 is perfumed kerosene, and it's a lubricant. You may well have inadvertently lubricated those first slugs meaning they would have zipped out at a higher velocity which upsets their aerodynamics.

Clean them the same way again, and see if you can repeat the keyhole anomaly.

I'm also curious about whether or not the keyholes were vertical.

 

[Apple a Day]

Blackhawk,
Usually I bring the targets home to glare at and study but this time I tossed them I wish there was a smackforehead smiley
I can't recall for the .22 but the first .357 smacked horizontaly. It went low and right of the POA. It made a great big oval tear. The second might or might not have been wacky but the hole was bigger than the other normal shots. It was a wee high and slightly right. The rounds were handed to me by a buddy... may or may not have been reloads. From now on I am sticking to stuff that I buy. The stuff I bought and used were all right on the money.
For the .22 LR I was using Stingers for the first time out of that particular revolver. My impression is that they are hotter than most.

 

[Blackhawk]

Thanks, Apple.

I've never had a gun keyhole, and I'd like to find a recipe for making that happen to add to some pet theories I tend to keep feeding.

 

[Sactown]

It made a great big oval tear.

I think blade67 is on the right track. Could the oval tear be a result of the undersized bullet tumbling? I think I remember reading about really old milsurps with worn out bores where the bullet tumbles and results in oval shaped holes.

 

[J Miller]

The rounds were handed to me by a buddy... may or may not have been reloads.

Since the offending ammo was unknown, and your own ammo worked properly, I'd blame it on the ammo untill proven wrong.
When I go to the range I almost never swab out the bore of my guns. I probably should, but I usually just forget. I use Hoppes too and have never had a problem with keyholes after cleaning a gun.

I have had keyholes. Usually caused by grosly undersized bullets, defective ammo, (or in the case of one .22 revolver) being out of time.

At one time I had a target with several perfect sideways bullet holes. You could even see the lube and crimp groves in the outline of the bullet holes.