Attention eddie coyle, Cast vs. Jacketed

[greencobra]

I'm self a taught reloader...going on close to 45 years. There is one thing that puzzles me to no end...why are starting loads different for the same weight cast vs. jacketed bullets? Just one of those mysteries of life I need to know before I die!

 

[DW357]

I always thought it was due to jacketed bullets having more resistance (in the bore) than bare lead bullets so you'll need less powder to force a lead bullet down the bore compared to jacketed? But I'll let more experienced people chime in.

 

[EddieCoyle]

I always thought it was due to jacketed bullets having more resistance (in the bore) than bare lead bullets so you'll need less powder to force a lead bullet down the bore compared to jacketed? But I'll let more experienced people chime in.

This.

Anyone that's ever had to clear a squib with both can attest to this.

 

[DW357]

This.

Anyone that's ever had to clear a squib with both can attest to this.

I can only attest to clearing a squib with a plated bullet

 

[84ta406]

I loaded very small batch of coated bullets using data for LRN bullets recently. Should I be worried? 9mm using CFE pistol if that matters.

I was curious when I was looking up the data as well, just figured LRN would be best for the Bayou bullets I used.

 

[EddieCoyle]

Should I be worried?

Nope.

 

[Gammon]

I have noted a great discrepancy between recommended loads for jacketed and lead bullets. I believe this is because many reloading manuals are written by bullet manufacturers, a la Hornaday who sell swaged lead bullets. They list reloading data for their swaged bullets which aren't much good over 750 fps.

 

[mac1911]

Push lead to fast or to slow and it's basically going to obturate differently.
Lead also requires different hardness and different lubes....then you get into gas checking.
I can push a cast 30-06 gas checked with a hard lino bullet to about 2500fps. The powder needed to reach these levels is several grains less than my FMJ loads.