How To Question # 3

First a little background. In the early 70's I learned to reload and used all RCBS products. Times were good and I shot a lot so reloading came natural to me. It was a time of such greats as Massad F. Ayoob and Jeff Cooper. As my family grew I gave up shooting and reloading, now I am back to reloading and things have really changed. Primers, gun powder and ammunition are scarce and quite spendy. I cannot believe that $39.00 for CCI 500 small pistols is going rate, if you can find them. Bullets are still fairly cheap and seem quite plentiful.
So this is my question: just what is the difference between Copper Plating and full metal jacket and why? I use the copper plated bullets and find nothing wrong with them, so be it: hollow point, round nose or flat point. When I examine the bullet after hitting a hard target I see nothing but deformed lead, no sign of copper plating. When I shoot full metal jacket bullets at hard target I find crumpled copper and deformed lead bullet. In no way does FMJ make the bullet more lethal. So, is there an advantage to using FMJ that I am missing? When I was reloading 34+ years ago it was FMJ or hard lead bullets being used.
Please, let there be no argumentative replies.....

Copper plated bullets are thinly plated. Load data would be similar (not necessarily exactly the same) to lead bullet load data. Berry's says use the same data as for lead boolits, Rainier says use lowest jacketed bullet data for bullets of the same construction such as round nose, truncated cone, hollow point etc. I've used Berry's not Rainier.:smile:

What cartridge are you loading for?

In general, you can't push the plated bullets as fast as you can jacketed, but depending on the cartridge there may be no real difference. With the .45ACP for instance, there is no difference in loading data and no real difference in performance except the plated and cast will give you slightly higher velocities for the same charge level than jacketed. The biggest issue with plated or commercial cast is that they are generally undersized with respect to the groove diameter (they need to be between .001-.003" larger than jacketed for best obturation and accuracy, usually they are not). Hard and undersized bullets are much more prone to both barrel leading and inaccuracy compared to properly sized softer cast/swaged/plated bullets. Some pistols don't seem to care either way what gets stuffed into them, others are very picky. Just like women. Unlike women, the picky ones tend to be much more accurate. I'm not sure how much more accurate picky women are as I don't make a habit of shooting them in my pistols.

Well I use the data sheet for IMR 700X and it gives me a load Of 3. 8 t0 4.2 grains; I load to 4.0 and that is for 9mm pistol.
Hymn " obturation" an interesting word about the obstruction of a body part.
I notice little difference in accuracy with plated vs full metal jacket bullets.
I thank all for their comments.
rocky