necking down .308 to .243

RoscoeT

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I sometimes come across free .308 win brass.

I've no use for it and my friend who I give it to, shoots 308 but has not started to load yet. Keeps saying "some day".

since it's so close to .243 can I neck it down and use it easily?

If so, is it worth the extra work? If it's good brass especially.
 
Necking 308 brass down to 243 will cause your neck thickness to grow, like from .0135" to around .0180" to around .0220", which maybe fine, depends on your chamber neck diameter. You can always try one, neck it down and seat a bullet on it, mic it, if the 308 to 243 brass neck diameter is over your fired case neck diameter in your 243, you can not shoot it or even chamber it, without neck turning.

neck diameters...
.020 x 2 (two sides) + .243 = .283" (very big)
.0135x2+.243=.270"


Measure a fired round and do the math or if you don't have a caliper or inside neck mic... make 1 dummy round (NO POWDER) and see if it will chamber without leaving marks on the neck.... (smoke it up too with a candle in the neck/shoulder to bullet area after you size one down and seat your bullet....) and "spoon" feed it into the chamber and then use the bolt to close the action. Extract carefully and put pressure on the case so the ejector doesn't make marks as the case makes it way out of the action.

Agree with s22-250 2 posts down, NO special die needed here, just lots of time and lots of elbow grease and a small amout of sizing die wax LOL
 
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you can make 243 out of
6mm rem
30-06
308
but a special die or trimmer is required so, time & price is not worth it unless you have thousands of brass and lots of time

you could sell / swap it and and get what you are looking for as lots of people are looking for non military and military reloadable brass:)

ps sort and sell by head stamp / brass/ nickle
 
you can make 243 out of
6mm rem
30-06
308
but a special die or trimmer is required so, time & price is not worth it unless you have thousands of brass and lots of time

you could sell / swap it and and get what you are looking for as lots of people are looking for non military and military reloadable brass:)

ps sort and sell by head stamp / brass/ nickle

Sorry but that is incorrect.
I have been resizing 308 to 243 using only a RCBS full length sizing die for the past 40 years. One must be sure to lube the 308 case very well or it will stick. My chamber neck on the rifle is tight so I do have to outside neck turn the resized brass.

Cheers
 
Sorry but that is incorrect.
I have been resizing 308 to 243 using only a RCBS full length sizing die for the past 40 years. One must be sure to lube the 308 case very well or it will stick. My chamber neck on the rifle is tight so I do have to outside neck turn the resized brass.

Cheers


What do you use to "outside neck turn the resized brass"?
 
you can make 243 out of
6mm rem
30-06
308
but a special die or trimmer is required so, time & price is not worth it unless you have thousands of brass and lots of time

you could sell / swap it and and get what you are looking for as lots of people are looking for non military and military reloadable brass:)

ps sort and sell by head stamp / brass/ nickle


Anyone that would WANT to try and make 243 brass out of 30-06 brass is frikken cheap or desperate. WAY too much labour. The 6 Rem is 5mm longer and would require a ton of trimming too.

The 243, 7-08, 260, 308 Win, and 338 federal are all the same case with different sized necks.

If you want precision brass, buy lapua 243 and be done with it. If you want a cheap source of brass, buy the bulk Remington stuff and save yourself a whole bunch of nonsense.
 
Years ago, a RCBS die set to make .243 out of almost anything longer fell into my hands. It includes a file type trim die - run in the case, cut it off with a hacksaw, file to length. A reamer die removes excess neck thickness at the .25 caliber stage of forming. Does a great job. BUT, why bother?
About the only reason to get set up for this kind of reforming is if the case is one that is simply not otherwise available.
 
Years ago, a RCBS die set to make .243 out of almost anything longer fell into my hands. It includes a file type trim die - run in the case, cut it off with a hacksaw, file to length. A reamer die removes excess neck thickness at the .25 caliber stage of forming. Does a great job. BUT, why bother?
About the only reason to get set up for this kind of reforming is if the case is one that is simply not otherwise available.

Yeah, that pretty much answers my question. As I suspected, it's more work than it's worth.

If it was just a matter of putting .308 brass in my .243 FL die then I would try it.
 
As mentioned, it is as simple as putting your .308 brass in your .243 die. THen, you can check to see if the neck diameter is too large. Depending on your rifle chamber you might not have to neck turn.
Try a sample case in your rifle, loading a dummy round with a bullet to see how it works.
I always full length size in a .308 die first.
 
What do you use to "outside neck turn the resized brass"?

I do not know if this applies to other case length trimmers.

I use a Forster case length trimmer, hand powered to trim my cases. You can buy a small inexpensive attachment that will convert the trimmer to an outside neck reamer. As far as I know this stuff is readily available.

Check WSS website, I'm pretty sure it is there.

As a side note, since I have the time all of my brass is outside neck turned. Yeah I know it does not contribute much to accuracy in the normal everyday rifle. For me it is therapy to be doing something firearms related during cold winter days.
 
Measure a fired round and do the math or if you don't have a caliper or inside neck mic... make 1 dummy round (NO POWDER) and see if it will chamber without leaving marks on the neck.... (smoke it up too with a candle in the neck/shoulder to bullet area after you size one down and seat your bullet....) and "spoon" feed it into the chamber and then use the bolt to close the action. Extract carefully and put pressure on the case so the ejector doesn't make marks as the case makes it way out of the action

And ( NO PRIMER )
 
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