Fixed my 9mm tumbling issue!

[chris in va]

Finally, no more keyholing.



After 12 different combinations, I found the 3.2gr 231 and water dropped to work the best (lower left). These were fired at 20 yards from my CZ 75BD. Barrel was scrubbed clean after each 20 rounds. Make note of the keyholing with air cooled boolits and 3.2gr on the lower right.

I'll probably try and find a 147gr mold, or just a 124gr RN instead of the TC like I've been using. Such a relief to finally get it to punch round holes for a change!

 

[floydster]

chris,
After reading your post I would like to make comment, but don't know what to say.
I load for seven different handgun calibers and have never had a tumbling bullet problem using cast bullets from many different sources.

I have shot many thousand rounds thru my 9mm CZ's using many different loads so I am at a loss as far as bullet tumbling is concerned.

Maybe someone with more experience would have some input. It maybe a paper target problem.

Am glad you have the tumbling ( keyholing) problem solved, but would like to know the real reason it happened.

Floyd

 

[PCJim]

Chris, glad you've fixed your problem.

I have not cast boolits, but used to cast fishing sinkers back in the day. I sometimes had a tough time getting consistent casts due to air pockets that would develop. I mention this only because I was wondering if maybe your keyholeing boolits maybe had similar problems? Did you weigh the bullets you had cast prior to shooting them to insure they had a consistent weight (absent air pockets)? Just thinking out loud here.....

 

[Unclenick]

Chris,

I've twice run into serious tumbling issues with lead bullets in handguns. In both instances (one a .357 barrel on a Dan Wesson revolver, and the other a .22 LR barrel on a Smith & Wesson Mod.41) the bore was off-center from the rifling. This was apparently due to the bore being reamed a little oversize, so the rifling button subsequently was able to push through it off-center. This made the lands taller on one side of the muzzle than the other. Unfortunately, the only correction is barrel replacement.

If the barrel twist is such that longer, heavier bullets only stabilize marginally, then an uneven muzzle crown can also tumble them by allowing muzzle blast to tip the bullet more than it can recover from in flight. Recrowning is simple and not expensive.

Unload the gun and open the action and use a magnifying loupe to examine the muzzle for either condition.

 

[Russ5924]

I have a Taurus 905 9mm that will keyhole about any cast bullet. FMJ seems to work with out a problem. I tried three different powders and bullets from355 to 356 and was so high in grains of powder and lowering the COLA the last bunch I wouldn't even shoot I took them apart