Forming 260 from 243 or 7mm-08, which is best?

spradley

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Which do you guys think makes the best 260 brass besides real 260 brass?

I've made it from 7mm-08 and haven't noticed any issues.

Today I caught two bags of 243 at Bass Pro and grabbed them up as I remember some make 260 from that.

thanks,
Gary
 

Fuzzball

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"I've made it from 7mm-08 and haven't noticed any issues."

Both ways will work but that was best.

Case necks are usually a sloppy chamber fit, expanding up thins and makes it worse. Plus, with necking up, its possible to get the 'dredded donut' at the base of the new necks.
 

Fuzzball

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"Funny, I made 7mm08 from Lapua 260 brass. No donuts and it works great."

What's 'funny' about it? Note I only said it's possible, .... is it possible you leaped before you looked?
 

Trapshooter12

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I have necked both. The 243 I split a couple necks even after annealing. I also had a split neck on a 7-08 also couldn't figure that one out.

One thing to look for is the price on the cases I use Win brass and the 243 is cheaper than the 08 by a couple bucks in some places.
 

buffybuster

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Having done it both ways; my preference is to Neck Down rather than up (no expander ball to drag through the neck). But satisfactory results can be had either way.
 

shoot4fun

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    "Funny, I made 7mm08 from Lapua 260 brass. No donuts and it works great."

    What's 'funny' about it? Note I only said it's possible, .... is it possible you leaped before you looked?

    Pretty touchy there FUZZ. I was not posting as a slap to your post. Folks round here are getting too thin skinned.
     

    shoot4fun

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    Having done it both ways; my preference is to Neck Down rather than up (no expander ball to drag through the neck). But satisfactory results can be had either way.

    Made a lot of 6PPC from 220 Russian. No other good way to get to 6PPC so you have to neck up. I use an expander die to do it.
    When I necked up from 260 to 7mm08 I used two steps. In all honesty it really was not worth the trouble and I won't do it again. WW brass can do the job just fine.
     

    turbo54

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    Funny, I made 7mm08 from Lapua 260 brass. No donuts and it works great.

    How many times have you fired that brass?

    I can get 2 firings max on lapua 6.5-284 brass in my 284 before the donut arrives.

    Is it possible you're getting donuts and not noticing it?
     

    shoot4fun

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    I have PPC brass that has been fired as many as twenty times without it showing up. The Brass mentioned in this post also has more than two firings. I would definitely notice donuts because those long 168 SMK seat down below where donuts form.
     

    kyshootnman

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    Having tried both in my 260, I have noticed the gun liking 243 brass better. I using Redding dies and use a taper sizing button when necking them up. It runs smooth in the brass with little to no force. I have no donuts either.
     

    Fuzzball

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    "Folks round here are getting too thin skinned. "

    You misunderstand; I'm not thin skinned at all. I thought your "funny" wisdom was kinda funny/silly and pointless because you added nothing useful to help with the OPs question but it sure didn't bother me for you to do that! :)