.430 vs .431

[Lee Q. Loader]

I really liked the 215 coated SWC from Brazos. I say "liked" because they discontinued it.
Without having ever slugged my barrel, I just always bought the ones sized to .431 vs the other choice which was .430.

When they discontinued the bullet they ran out of .431 first so I ordered the .430, hoping they would shoot just as well.
Wrong! My 20 yd groups went from the size of a plum to the size of a grapefruit.

Is there anyway to improve the accuracy of an undersized bullet? Speed it up? Slow it down?
Or maybe the answer is, it just doesn't fit my barrel well and and will never shoot well.

Currently pushing it about 1200 FPS with 10.0 grains of Herco.

 

[Walkalong]

Magnus makes a 215 Gr SWC in .432 if they're still around, shoots great.

I suspect the bullets are undersized and it would take more pressure to maybe bump them up, but it may not work, there may not be room for more pressure.

They don't fit the throats now most likely.

That said, where is the leading in the barrel?

 

[GooseGestapo]

1. Melt it down and add some pure lead and recast it. (Softens)
2. #1 and size to larger diameter.

Been there and done both….

3. Place base, or flat nose on anvil or other flat hard surface, and strike with a hammer. Then resize down to desired size.
4. Use a somewhat faster powder (I’ve had luck with RedDot, and Bullseye, ) to “whack” the base of the bullet during firing to obturate the base of the bullet, expanding it to the bore. Usually this is best done in a revolver where the throat in the cylinder is larger than the bore, and is facilitated by the forcing cone in the barrel.

 

[GeoDudeFlorida]

1. Melt it down and add some pure lead and recast it. (Softens)
2. #1 and size to larger diameter.

Been there and done both….

3. Place base, or flat nose on anvil or other flat hard surface, and strike with a hammer. Then resize down to desired size.
4. Use a somewhat faster powder (I’ve had luck with RedDot, and Bullseye, ) to “whack” the base of the bullet during firing to obturate the base of the bullet, expanding it to the bore. Usually this is best done in a revolver where the throat in the cylinder is larger than the bore, and is facilitated by the forcing cone in the barrel.

From the post it seems unlikely the OP is casting or has the capacity/equipment to do so. But, the whacking trick works and isn’t all that hard. I recommend getting a sizing die first.

 

[GeoDudeFlorida]

I really liked the 215 coated SWC from Brazos. I say "liked" because they discontinued it.
Without having ever slugged my barrel, I just always bought the ones sized to .431 vs the other choice which was .430.

When they discontinued the bullet they ran out of .431 first so I ordered the .430, hoping they would shoot just as well.
Wrong! My 20 yd groups went from the size of a plum to the size of a grapefruit.

Is there anyway to improve the accuracy of an undersized bullet? Speed it up? Slow it down?
Or maybe the answer is, it just doesn't fit my barrel well and and will never shoot well.

Currently pushing it about 1200 FPS with 10.0 grains of Herco.

Stateline sells .431” https://statelinebullets.com/shop/cast-pistol-bullets/44-cal-cast-pistol-bullets/44-245-gr-swc/

 

[sparkyv]

Learned something new!

3. Place base, or flat nose on anvil or other flat hard surface, and strike with a hammer. Then resize down to desired size.

the whacking trick works and isn’t all that hard. I recommend getting a sizing die first.

 

[Lee Q. Loader]

Magnus makes a 215 Gr SWC in .432 if they're still around, shoots great.

I suspect the bullets are undersized and it would take more pressure to maybe bump them up, but it may not work, there may not be room for more pressure.

They don't fit the throats now most likely.

That said, where is the leading in the barrel?

Leading is about midway in the 5.5" barrel, maybe a bit more towards the muzzle.

 

[CoalCrackerAl]

Although not .431. These work great in my SBH and CVA hunter.
Hi-Tek .44 – Summers Enterprises (summersenterprisesllc.com)