I was going to order some 243 brass then remembered I have some once fired 308 brass a friend gave me.What are the steps necessary to convert 243 from 308?I have never used or made different cal brass before.

Order

Anneal, lube, form, and trim.

I have made alot of different cartrdiges from .06 brass. It works and if one is shy on money it can save you some.I have not made the .243 out of .308,but if the length turns out ok,you are good to go. I think I even made some 7.65 Argintine mauser brass out of .308 and it was a tad short.Still worked.

Guys who do wildcatting do it all the time.For years that was the only way ot get3 5 Whelen brass. Make it out of.06.Same with .358 and making it out of .308 brass

I usually start by removing the decapping pin, expander ball, Lube the brass and then run it thru the FL sizer.

Then I run it back thru again with the expander ball in place
Check the length and trim if required. If OK, load them up with a min load to fire form and go shoot for fun.Some guys get anal about it and anneal the cases,I have at times,and others times not.. FL size again and load as you would any other case. It helps if you mark the case head with red magic marker or? just to keep you honest as it will still have the,.308 head stamp on it
Some guys also say you will need to turn the necks. Again I have done both.I have made quite a few .308 cases out of mil .06 brass and never have annealed them or turned the necks.
They all seem to kill elk and deer just as effectively

Neck thickness? Anneal? Like I said, order 243 cases.

Agree. And I have nearly two bags of WW I'll sell cheap.


Kaiser Norton

Call me lazy........i will buy Hey Kaiser PM sent

That is some of the best advise you will ever get.

I have formed 243, 25/06, 7x57, 270's out of military 30/06 for a commercial loader when I was a kid.
30/06 brass was $50 for a 50gallon drum, and we sold the loaded ammo for $3.50 for 20 rounds...1968, and the post office used to deliver 20lb kegs of powder to our door step.

Just buy the 243 brass, otherwise you are in for the goat ropeing of a life time.

I'd rather neckdown and fireform false shoulders,than go up...............

+10

Oh come on guys....

Sure he can order some 243 brass, and maybe that is what he ought to do.

But I reached a point that I no longer had a 308, but did have a 243, and an abundant supply of 308 brass. I found that forming 243 from 308 is no more difficult than FL sizing a regular 243 case. Just pop it in the die and pull the handle, then trim to length. And I've had zero difficulties, with one exception.

If the brass has been worked a bit, you can get little pleats in the brass. If the brass is annealed, you don't have that problem. If you don't get pleats, you don't have to anneal.

It's easy peasy lemon squeezy.

Rollin' the false shoulder as well.

It'd be an inordinate 243 Factory Rifle,that had neck clearance issues..............

Ive never tried the .308-.243 route but I did do a batch of 7x57s out of .30-06s
and it was a PITA Maux Faux Braux....

+1

.30 to .24 would be a PITA...

I run .308's to make my .358's no sweat... Trim and load.
But the other way is just too much trouble for the results IMO.
I'd just buy, or trade the .308's for your .243s.

I don't see the problem. I have formed 35 Whelen brass by necking up 30-06, and 7-08 brass by necking up 243. I could see if you were converting 308 to 243 you might have to turn the necks.

The OP never asked what he should do,he asked what is involved in making. 243 cases from.308.If folks would read post and then answer the original question, a lot of space would be saved.I have made 7x57 cases out of LC 69 mil brass and I incurred no problems.

Can't figure out why some , instead of answering a question don't just say." I don't know"

Even more space would be saved by not answering, rather than posting "I don't know."

Just sayin'...

I have done it before & it is pretty simple. At the minimum run the .308 cases up in the .243 sizing die and then fire form & trim. You might have to thin the neck wall by turning them. I didn't.

I tried 5 of the 308 to 243 one time. I wound up using them for snap caps for my wife and daughters to practice with. Good for nothing else.

Buy some 243 brass. It's cheaper in the long run.

I see this is a pretty old thread but for someone new reading this, I thought it might do some good.

I have made lots of .243 brass out of .308 and once you've ironed out the quirks, it is pretty straightforward.

Trouble you might have is if you get any lube on the outside of the neck or shoulder area. Then, you can get shoulder wrinkles or even serious lube dents-keep the lube away from neck and shoulder area and no troubles.

Go to the Natural Food Store and get a jar of lanolin. It works way better than any sizing lube they sell-unless you like sticking cases in dies.

Put the lube on the outside of the .308 case to be sized and none on neck or shoulder area.

Take a small rifle brush and run it inside the neck and clean out the crud and carbon as best as you can.

Take a small amount of lanolin on your finger or put some on a paper towel and just get a little ring of it inside the case mouth so your expander button doesn't stick.

Wipe the outside of the neck and shoulder area clean.

Now size in your .243 small base die set and-bingo. Good idea to fireform and then see if a .243 bullet fits inside easily.
If it does, no reaming necessary. Trim and load-or ream if necessary.

If you have all the stuff to ream and trim already, then no big deal. You may have to buy a neck reamer if you don't have one already but that's about all it takes.

At today's prices for brass, it is worth it to go the .308 resize route since you can usually pick that brass up at gun shows pretty cheap.