Monday, May 5, 2014

Scientist Wallace McDaniel evaluates cast bullets.


Recently aquired a Lee .358" mould to cast 158gr SWCGC bullets for .38/.357 loads. Went w/the gas check design as it prevents leading, something I've experienced in these calibres quite frequently w/commercial cast plain base bullets. There's a lot that can contribute to leading (metal hardness, obturation, lube, velocity, etc, etc...) but the gas check solves the problem right off'n the bat.

These bullets look good...I like the design. I had some old .35 calibre gas checks I got in a trade deal w/lots of other stuff...why not put em to good use? I weigh all the bullets to cull out the ones that might have air pockets & other flaws...to the best of my ability. Close inspection will most of the time reveal the ones that didnt fully fill out the mould. I am "quality control" of my ammo. With all these steps, I havta say I'm very disappointed in the initial attempts to find a load that will deliver acceptable accuracy. All loads were assembled in .38 Special cases & primed with Winchester small pistol primers.
 
Test revolvers were three S&W's, all in .357 Magnum...a 4" M19, a 6" M19-3 and a 6" M27-3. All groups were 5-shots from sand bags @ 25 yards. None of the 3 loads I tried were any where close to what I was hoping for.
 
First load was with 4.0grs Bullseye.  Groups were 5" (4 in 2.5") .... 6.5" (4 in 4.25") .... 6" (4 in 2.75") ....even without a flyer, these groups were not what the revolvers normally shoot.
 
2nd attempt was 6.0grs BlueDot. (didnt try these in the 4") ... 3.875" (4 in 3.75")  .....  5.813" ( 4 in 4.938")
 
3rd load was 3.8grs TiteGroup (not tested in 4"bbl) .... 6.06" (4 in 2.375") .... 3.94" (4 in 3.75")
 
Looks like these bullets may never shoot, no matter the powder charge used. Anyone got any ideas? So far I'm disappointed.       

4 comments:

TXGunGeek said...

What diameter bullets is your mold throwing? have you slugged your barrels to get their size? I had issues with .44's that was solved by shooting bullets sized to .429 in lubrisizer instead of using as thrown.

Old NFO said...

NO help here... sorry...

Ritchie said...

Do these revolvers shoot significantly better with other ammunition? If so, you have the problem surrounded. If not, you might look at the size of the cylinder throats, which should be slightly (by say, a cigarette paper at most)larger than the barrel groove dia. You probably know this already. Does the flyer always come from the same chamber?

JohninMd.(help?!??) said...

Check the dia. of your cylinder throats vs. bore dia. Size the slugs to fit the cylinder, as long as that's smaller than bore size, accuracy should improve. Gotta say, 2.5" - 3" @ 25yds, w/1 flyer opening the group sounds like operator fudge on one out of five. Just sayin'......