cartridge conversion 308 to 243 win -- HELP!!

rookie wildcat said:
I wanted to do this early in my reloading days. A friend had a handi-rifle in .243 so I told him I would load him some rounds. Borrowed a set of .243 dies, crushed the first dozen, asked for help, had case forming (both up AND down) explained in detail, borrowed a set of forming dies. Hardest part after that was going back and forth to get the necks thinned.
Haven't done it since. Easier (and cheaper) to get .243 brass.
I do, however, still make 7mm-08 brass from .308 brass, but I made my own step die by polishing out the neck of a second 7mm-08 die.
OP, you are wasting your time without some fairly specialized equipment. I can make this easier, I have a couple of hundred NEW winchester cases I haven't gotten to yet (my wife shoots far less than I do) and I would be willing to part with a pkg of 50 for what I paid for them plus $5 for shipping. That'd be 28.00 plus tax, for 29.40 and $5 would make it 34.40. If you are interested, PM me.
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I have found some 243 brass from a wtb post i put up in the EE area. I have learned a great deal from this thread and the case conversion route will be pushed down my to do list until I have been doing this for awhile and collected some more tools and experience. I am new to this forum and I have had a welcome feeling with the few posts I have made here and seeing no slander and trolling is awesome. Thanks to everyone who has helped me here in the last few days!!

Happy shooting to all!!!

-Lazi
 
I have run hundreds of 308 down to 243 and never annealed one of them nor did I do stepping, just lube them up good in RCBS case lube and run them through a 243 full length die set to bump the shell holder hard. Don't ever recall losing a single case. I have done hundreds of IVI, LC, and DA military brass as well without any grief at all.
 
c-fbmi said:
I have run hundreds of 308 down to 243 and never annealed one of them nor did I do stepping, just lube them up good in RCBS case lube and run them through a 243 full length die set to bump the shell holder hard. Don't ever recall losing a single case. I have done hundreds of IVI, LC, and DA military brass as well without any grief at all.
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You must have a heavy duty press. I don't think my lyman t mag 2 has it in it to do it in one swipe. That and my bench isn't as sturdy as it needs to be.

Edit...
I ran all the 308 brass... Lubed em up good. (Not too much) centered the case neck gently in the die then gave a smooth firm push into the die and they formed nicely. They are actually about .03 shorter Than my trim to length in my lyman manual. Inside diameter is about .240 should hold nice and snug. And once they fire form to my chamber I think they will do fine. I lost only 26 out of the 104 free found brass I ran thru my die tonight. Here is a photo.

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Glad hear it worked out for ya. I have sized quite a few 7mm-08 out of 308 brass. The only thing I would caution is that I would measure the necks after you have seated the bullets in them as the neck will be a bit thicker. I found that when I used Federal brass (heavy brass in the necks) the final 7mm-08 round had a neck thickness that was close to the max. I'm kind of a chicken sh1t reloader so I quit using Federal brass when making 7mm-08 out of 308 so as I would not end up with oversize necks. all other brands seemed to work fine.
 
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Congrats. I am now going to set up my press and check this again. Perhaps what I should have been told is, "You can't do this in one step on a Challenger!". Everything I have ever formed since the .243 incident has been done on the RockChucker and has only been basically one calibre difference. These went without a problem. I haven't bothered with .243 again since I no longer have access to the forming dies and didn't own a rifle in that calibre. I will try it today and see.

Edit: So, I managed the form the brass. .308 direct to .243. It required very slow stroke and LOTS of lube. It was all Winchester brass except the last two, they were Remington, and the necks are visibly thicker (numbers with the pics). The first simply crushed. The second sized, but I used about 20 strokes to ease it in to the die until it was resized. The third, crushed. The forth I added more lube and accomplished the task in 6 strokes. The final two used increased lube and a really slow, constant stroke. So, it CAN BE DONE. I used my Lee Classic cast for this, then switched it over to the RockChucker for the last one. Wish I had had either of these presses when I was younger, would not have bothered my friends for dies and tooling.
The Winchester rounds all chambered well in the rifle, and so did the Remington, but I believe I will turn those necks a bit, just to be safe.
Technical issues abound, but once my phone is charged, I will get pics up.
Edit: Pics up. Sorry. Can't ever remember which way is up and Photobucket sucks for editing. I am NOT good at this. Hence the rarity of pics.

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Inside neck dimension is consistent at .238".

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Outside neck dimension, .277", of a fired case, fired in my wife's rifle.

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Outside neck radius, .2795", Remington cases

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Outside neck radius, .2705", Winchester cases
 
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I too, have resized directly from 308 to 243 with one pass through the RCBS 243 die. 308 brass sized down was both commercial and military brass.
I never annealed them first, either.
This is why I suggested early in this thread that he try sizing them without first annealing them.
 
H4831 said:
I too, have resized directly from 308 to 243 with one pass through the RCBS 243 die. 308 brass sized down was both commercial and military brass.
I never annealed them first, either.
This is why I suggested early in this thread that he try sizing them without first annealing them.
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And I thank you for the suggestion. I was over complicating the whole process. And For the record I am using lyman dies.
 
Rookie wildcat. Where did you find the neck turning tool? I have checked a few of my local gun shops in calgary but everyone laughs at me lol. Seems to be a thing of the past to work cases. I was getting consistent .240 inside diameter on the mouths. And I chambered a few and they seem to be okay. But they are visibly thicker than factory 243 my case length is also about 30-40 thou short. Which is fine I'll be reloading 95 grain boat tail ballistic tips that are super long

Edit... I also never got the multiple stroke sizing to work.it was all steady one shot. Sometime I had to get a little western on it to get it sized but too slow or too fast seemed to crush the shoulder.

Ps happy new year! Just spent new years eve reloading 10 different charges in 2 powders for my 30 30 to see if I can find a one moa load out of my 18" barrel lol.
 
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if your necks measure .269-.270 with a bullet seated in the case you may not have to neck turn.
 
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