Cast 9mm question

[MtJerry]

I cast some Lee TL356-124-TC to use in my Wife's new Taurus Millenium. We went to the range this weekend and about half of them keyholed.

There were loaded as cast (WW w/ a pinch of tin), lubed with LLA and loaded with 3.5gr of 231 which is a middle of the road load as far as velocity. I did get moderate leading in the barrel.

She was limpwristing quite a bit at the range with numerous malfunctions. I ruled the load as the cause of the malfunctions yesterday after I shot over 100 rounds of the same load with no malfunctions.

Now, my questions is this ... if I boost the velocity to gain more pressure, I should get a better orbutration (sp) and eliminate the keyholing and leading.

I will also change powder to WSF as 231 was creating more smoke than momma was happy with.

I am also considering changing alloy to 50/50 ww/pb and giving them a second coat of LLA.


Any other ideas??

[docone31]

I use the 120TC from Lee. I size to .357 and pan lube. I have not yet gotten any issues with that load. No leading, no key holes. I have the Star Modelo 9mm which is supposed to be real picky with projectiles.
How did the groove measure in comparison to the as dropped casting? Fit is an issue with key-holeing.
You might try sixing the tin, and water dropping.
Just food for thought.

[Cloudpeak]

I've used the 124 gr TL RN Lee and 105 gr SWC Lee in several 9mm's, most recently a STI Trojan. They are sized .357" and tumbled lubed with LLA. Both bullets are very accurate, no tumbling and with very minimal leading.

Cloudpeak

[jdgabbard]

I agree, I use that boolit in my .38s and in my 9mms. I opened mine up a bit to drop bigger boolits, but I size them to the diameter I need and they always shoot fine.

[z4lunch]

Steve here... My Sig P226 9mm slugs at .358
Steve

[Kuato]

MtJerry, have you slugged your barrel to see what the diameter of your bore is? I cast & load the same boolit & have had ZERO keyholing or malfunctions in any of my 9mm pistols or carbines. I size to .356 for my 9s & load em as cast for 38s (they drop at .358).

3.5 gr of 231 is actually on the low end of the scale. My preferred load for my S&W Mod 39 is 5gr of AA5. Very accurate, burns clean & no leading. I lube with LLA. 2 coats. 1 before sizing & 1 after.. The 9MM Luger can be a tricky cartridge to load.
Chamber diameters can vary greatly from gun to gun in 9mm. When I started loading that boolit, I loaded them as cast(.358). It would chamber in a few of my pistols & didn't in others.

Also. the malfunctions are in part due to limpwristing. Being that the loads you have are low end, the the slide has less force unlocking & moving it back against spring tension. Add the fact that recoil is being absorbed by the wrist, you get malfunctions..

What weight are the boolits you cast? What diameter are they?

[Echo]

And my guess is that the smoke is coming from the lube, not the powder...

[Gunslinger]

I've shot thousands of that kind of bullet in my Tanfoglio and my 686. I lubesize them all to .357.

However I use a somewhat harder alloy. about 4-1 WW-lino. Never had leading nor keyholding.

[Curly James]

Check your OAL. Seat the bullet until it will just chamber or in some pistols just feed from the magazine. I would start with an OAL of 1.160 inches (make a dummy round) and then try a mid range load with the bullet sized to just fit the bore diameter. 9mm can be a little finicky about OAL. By the way, HS-6 is an excellent powder for 9mm loads. Good luck, CJ.

[sniper7369]

The twist rate of the rifling in the pistol is probably not spinning the bullet fast enough to stabilize it with the load you are using. Up the charge so the bullet gets a little more speed and it will probably be fine.

[redbear705]

I use W231 and it will shoot a little smokey but when I upped the charge a little the smoke lessened and the keyholeing went away.


JR

[MtJerry]

Thanks for the replies, I am gonna up the charge a bit and see of the keyholing goes away.

The other ideas (different powder and alloy) can wait.

THANKS!

[Wayne Smith]

Told ja you would get plenty of help here!

[MtJerry]

Told ja you would get plenty of help here!

You are / were right.

Notice my post count, I ain't a blabberfingers here, but this ain't my first trip to cast boolit heaven either!

:drinks: