Resizing jacketed bullets?

Slowbalt

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Any pointers on resizing commercial jacketed bullets? Can it be done? Is the resulting bullet of an acceptable quality/consistency? Do you need lube? If so what do you use?

For context, I would like to try to resize Campro 32 (.312) pistol bullets to .308 for plinking loads. Would be using a LEE sizing die.
 
I did a bunch of 50 cal bullets years ago. Where quite deformed as they were surplus pulls. Used a Lee sizing die. I can't remember if I used a light grease or just oil. But lubrication definitely helped. You are not coating them after so no need to worry about the lubricant. .004" isn't much. Go for it. Just make sure you are using a decent press.
 
For pistol I would try a few and see how they come out the sizing die.
Not first hand experience but I heard that you can get spring back on the copper jacket and then the jacket isn't fully bonded to the lead anymore or are they plated bullets?
 
I have read that it is done often, but never tried myself. Partially depends what you have on hand?? Might want to do some cerrosafe cast and measuring - your rifle might accept .309 or even .311 bullets - those sizes still listed for Lee Precision push through sizers - I believe there are other company's similar products as well.

I do know from sizing cast bullets with hard alloys to expect a smidgeon of "spring back" - even though the die says .324" or whatever, the bullet might need several passes through to get down to that size and stay that way.

Bullet diameter not really "cast in stone" - Hornady 9 Manual shows bullets from .310" to .312" for the 303 British, and .3105" in between, but none at the .311 that would have thought to be "correct". So, there is probably some nominally "30 caliber" that would do fine with Hornady's .310" bullets, but some won't. So what someone else did or did not do, may or may not have much to do with what is possible or desired in your rifle.
 
Pretty sure the usual lube used for bullet swaging is Lanolin and castor oil mix, but you can check on the Corbin's websites, each of the brothers has a pretty decent amount of info.

Personally, I'd just run some case lube over my fingers and run them through to see how they act.

Pretty sure the Campro are plated, not jacketed.
 
I've resized .32 jacketed to .30 for use in .30 mauser and .358 rifle bullets in 9mmx57 Mauser. No issues using lee dies, but I did go through them twice due to some spring-back. No lube was used. The bullets produced worked, but somewhat mediocre in my opinion, but in fairness, I didn't work up loads, just made them go "bang". Wouldn't wish to resize more than 2 thou using a one-step this method as it was difficult swagging them just that little bit. Maybe lube would have helped?
 
I've done several hundred 8mm .324 220gr surplus MG pulls form 8x63 Swedish to .318 for my gewehr 1888, with a decent press and a bit of oil they size fine and have had no issues with the jacket separating so far
 
a dude ran some .323 speers through a sizer an put them at .3135 /.314 fir my 303, they been shootin good but yet to take game with them
 
I do not believe you will end up with an accurate consistent bullet. The whole projectile will size down but the jacket tends to "spring back" resulting in a improperly supported core of lead. This is not the same as having a solidly correctly sized bullet cup which is then "pointed" into its final shape. I have seen it done but the results although safe to shoot did not group well at all.
 
I once used up a hundred Winchester power point bullets made for the .303 by running them through a lee sizer .308" and shooting them in my .308. I did lube them first, and they shot Ok for practise plinkers. i didn't try them for precision accuracy.
 
Been covered here many times. Here are some recent threads and one not so recent:

https://www.canadiangunnutz.com/for...9-How-much-can-you-size-down-a-plated-bullet?
https://www.canadiangunnutz.com/forum/showthread.php/2102779-310-123gr-bullets-resized-to-309-safe-in-308s?

https://www.canadiangunnutz.com/for...0-312-quot-0-314-quot-and-0-316-quot-Bullets?

Some will warn that:

1. it's dangerous to try (!) as the jacket will separate from the core and bad things will thus happen to the gun and/or to its intended target; and
2. its profile will change so dramatically that its flight will suffer to an unacceptable degree.​

Concerning #1 - no it won't. I've sized down bullets as much as 10 thou and then sectioned them and the jacket remained firmly bonded. I've shot about 100 of them and recovered about 10% and I observed the same thing after firing. The bullet is further sized down in the bore, significantly by the rifling, further locking the jacket to the core, so the notion of the core "squirting" loose is fantasy.

#2 - yes it will change the profile of the bullet, as the surface sized down will lengthen and the surface not sized down will remain the same. The threads shared above show some before and after sizing pictures and measurements. It changes a bit more (like every bullet) when it travels down the bore. This will affect flight, so if you're looking to do this in a target rifle be aware - it might unexpectedly improve trajectory! ;-)
 
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