OK, I am officially baffled.
In my Lee Die Set load data sheet, powder types and weights vary depending on the type of bullet I intend to load. 240 gr Lead says X grains of X powder, while 240 gr JSP says y grains and Y powder. So far, no problems.
Now....I go to the Hodgdon and Winchester websites and they only require bullet weight, with no mention of bullet "type".

Am I to understand bullet type doesn't matter as long as I consider the bullet weight?

In other words, on my Lee Load Chart, can I follow the 240gr JSP data to load a 240gr cast lead bullet?

Again, I hate to ask a simple question, but alas, at times I am a simple man! lol

Thanks in advance for any insight!

Short answer is yes.

As a rule, I like to load lead bullets slower than jacketed bullets.

A lead bullet will normally generate less pressure for a given powder charge because it takes less energy to force the lead bullet into the rifling vs a Jacket bullet.

But like Saeed said most people will load a lead bullet to a slower velocity(pressure) to help reduce leading of the barrel.

For me I use lead bullets for target and plinking and reduce the velocity. For hunting I normally load close to max provided it is accurate.

What they said about lead slugs. Also, Technically many sources will tell us that a reloader should start over whenever ANY component is changed. Even from similar bullets of the same weight. Personally I will often use the same data for X vs y bullet as long as they are the same weight and basic construction. For instance similar leaded bullets of the same weight, similar cup and core bullets of the same weight and so on. I also believe that going from a cup and core bullet to a monolithic can dramatically alter pressures, so they should have "specific" data references as well. Hope that helps.

I will confuse you some more.
you can use jacketed data for a cast bullet.

IF they take up approximately the same amount of the available case volume.
if they are real close in shape and length from the crimp groove downwards your good to go.
you will see higher velocity's from the cast bullet.

in some cases such as the 45 acp you can directly interchange one for the other by using jacketed data.
if you follow the above rule of case volume and have velocity's so similar you'd be pretty hard pressed to tell one from the other over a chronograph.

when your dealing with a rifle like the 30-30 the cast bullet can be driven faster than the jacketed bullet because of the lower engraving and consequently the peak pressure.


that doesn't mean you can't get into trouble by not paying attention to that case volume thing.
many powders are very sensitive to the amount of air space around them.

all of that goes out the window if you use too small of a too hard bullet and start leading up the barrel.

I'm learning...slowly but surely!
Thank you all for the input!