How much can you size down a plated bullet?

diegocn

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I'm trying to convert inexpensive pistol bullets into 8mm (.323) for plinking load in 8mm mauser.

The most plentiful ones I can think of is 9mm/357 caliber bullets. Is that too much to size down to 323? What's a general rule of thumb on how much you can size down a bullet? What would happen if one goes too far? Would it be hard/impossible to size, or would bullet damage be resulted?
 
I am always pleasantly surprised how satisfying a heavy cast bullet over shotgun powder is to shoot. If you can buy bullets in the 200 to 250 gr range, they will be accurate and have a satisfying kick and bang, and accurate beyond plinking range.
 
I've used lead cast for 308 before and couldn't quite get it tune in. There always seems to be lead coming out wih the cleaning patch even if I dial down the velocity (9.5gr-10gr trail boss for 170gr non gas checked). That's why I try to stay away from it.


The lebel idea is interesting. I'll give it a shot. Though back to the question, can I size down 9mn to 8mm?
 
Its possible to size them down in many steps through various sizing dies. 356 to 348 for example, then 348 to 323. You going to need lots of lube and strong press too. I tried swaging led 356 directly to 323, its hard and you will get lots of shaved led and distortion. Better start casting or just buy proper bullets.
 
Its possible to size them down in many steps through various sizing dies. 356 to 348 for example, then 348 to 323. You going to need lots of lube and strong press too. I tried swaging led 356 directly to 323, its hard and you will get lots of shaved led and distortion. Better start casting or just buy proper bullets.

X2 - I'd go 356 to 348, 348 to 338, 338 to 329 and 329 to 323. Unless you already have those sizers, you're looking at not saving, but spending $ and time to obtain something inferior to what you can just buy.

Of course the satisfaction of doing something like this is worth something.
 
X2 - I'd go 356 to 348, 348 to 338, 338 to 329 and 329 to 323. Unless you already have those sizers, you're looking at not saving, but spending $ and time to obtain something inferior to what you can just buy.

Of course the satisfaction of doing something like this is worth something.

Keep in mind he is talking about plated bullets. Copper is quite ductile but I'm not sure there is enough there to stretch much.
 
Keep in mind he is talking about plated bullets. Copper is quite ductile but I'm not sure there is enough there to stretch much.

Yes it works.

I took a Frontier CMJ 0.358" 158 gr plated bullet and sized it in two steps: 0.358" to 0.332" and then 0.332" to 0.323". The 0.332" is a custom die - the Lee 0.329" could substitute, but would be the limit for a first pass. I anticipated possible trouble with the first stage of resizing, but it re-sized with little effort.

When reduced to 0.323", the bullet grew in length by 0.100". An 11% reduction in diameter resulted in a 15% increase in length. If it had been a cylinder, it would have grown in length by about 23% (0.358 squared/0.323 squared. The length increases according to the square of the decrease in diameter) and remained a cylinder with the same volume (weight), but with different dimensions. However, the math is complex because it's not a cylinder, rather only the portion of the 0.358" bullet that's larger than 0.323" is affected - part of the nose and the complete body.

Frontier CMJ 0.358 to 0.323.jpg
 

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Sometimes I like being wrong. Very cool.

You weren't wrong, only skeptical. If the jacket had been thinner or poorly bonded it might have broken. Frontier makes a good bullet with its jacket being both relatively thick and well-bonded to the core.
 

This is why I love this forum. Thank you for trying it out for me. Time to order some lee sizing kit.

I'm pretty new to hullet sizing, what kind of lube should I be using? Since I'm sizing plated bullet, can I get away with case sizing lube (I'm using lee case sizing lube) or do I have to order some lee liquid alox?
 
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