44Mag CB keyholeing

[gore_point_1]

A buddy of mine got the itch to shoot his Ruger Alaskan in 44mag. He had a
hard time finding ammo, so he asked me to cast him a few rounds. I'm
just getting going with casting, so I don't have much experience yet.
I borrowed a LEE .429 SWC, non GC mold in 214gr. I cast a small
batch using approximately #2 alloy. They came out around .428 dia.
I lubed them up with liquid alox and then loaded them up. I used
10gr of Unique with WLP in RP brass cases. The load is supposed to
be 930fps according to the book. At the range, some of the rounds
were keyholeing. Is the keyholeing a function of the bullet size,
the powder load, the alloy or a combination of the above. Looking
back, my crimps weren't as stout as they could have been. Any
thoughts would be greatly appreciated.
-GP

[btroj]

The key holing is entirely a function of an undersized bullet. Bet the bore is leaded pretty heavily.

You would be better using a far softer alloy and a mould that throws a .431 or .432 bullet. Nothing leads like a hard, undersized bullet.

[725]

I suspect the barrel of the revolver is at least .429. Maybe more / maybe less. The relationship of the bore to bullet (or like we like to say "boolit") will work better if the boolit is .001 to .002 LARGER than the groove diameter. Right off the bat you are working against the stream with your measurements. Further, a hard roll crimp may reduce the boolit size as it leaves the case. Not much but at this point every little bit counts. There is a process here on the board called "beagling a mould". It will give you a slightly larger finished product. Do a search or wait for somebody to chime in with the procedure. I'd beagle that mould and use a light taper crimp to overcome your problems. (Lee makes a crimping die to help with the crimp) Stand by, others will jump in with some more good advice. Welcome aboard. Lots of good guys here.

[shoot-n-lead]

The key holing is entirely a function of an undersized bullet. Bet the bore is leaded pretty heavily.

You would be better using a far softer alloy and a mould that throws a .431 or .432 bullet. Nothing leads like a hard, undersized bullet.

In this case it is the undersized bullets...twist rate not matching bullet weight can also make bullets keyhole if the bullet does not stabilize.

[mdi]

As noted above, by btroj, your bullet is .003"-.004" too small. Easiest way to get clean shooting, accurate bullets is to size the bullets to match the cylinder throat diameter, regardless of how "hard" it is...

[MtGun44]

btroj is exactly right.

Too small, too hard. Try wwt alloy, air cooled at .430-.431 and I will
bet the results will be good to great.

Bill

[btroj]

Guys, don't ever forget that a slightly undersized soft bullet can swage up on firing to seal the bore and be OK. A hard bullet with a light load will never swage up.

Size and hardness work together with pressure. Hard isn't always the answer, specially with lighter loads.

[Hickok]

GP1, you are going to need some Chore boy and some elbow grease to clean the lead out of the bore!

[gore_point_1]

Guys,
Thanks for the advice and giving me a direction on how to proceed. Fortunately, the barrel wasn't leaded up to bad. We only shot a dozen or so rounds. The mold isn't mine, so I can't do to much with modifications. Maybe I'll have to buy a mold better suited to my needs.
GP1

[Jim..47]

Another possibilty is if you use the Lee factory crimp die. If so, make a new/small batch and load them without the LEE FCD. Just might be your problem, its happened to me already and I no long use the LL FCD on any bullets at all. If you check the bullets after going through the FCD you will find they are too small, compare to ones with the FCD.

[btroj]

If the bullets started at .428 the Lee FCD couldn't have done anything to make them worse. They were enoug undersized that another .002 smaller wasn't going to matter.

[Down South]

The key holing is entirely a function of an undersized bullet. Bet the bore is leaded pretty heavily.

You would be better using a far softer alloy and a mould that throws a .431 or .432 bullet. Nothing leads like a hard, undersized bullet.
What he said. Only time that I ever had a keyhole problem was with an undersized boolit.

[Wayne Smith]

Beagling is a temporary addition of heat proof tape to the mold. It does not change the mold permenantly, so feel free to look it up and do it. It is your absolute best option with this mold short of paper patching.