Forming .308 Win brass to .243 Win brass

[TheBlueEyedBear]

I have a question regarding forming brass: Does anyone know of a procedure to turn .308 Win brass to .243 Win brass. I tried taking the guts out of my .243 seating die a hoped the gradual slope of the seater would do the job, but it doesn't go anywhere near the shoulder leaving a large amount of .308 neck. I've searched the RCBS site for a forming die but did not find one.

Any suggestions??

Thanks.

Barry

 

[bheadboy]

308 has a sharper shoulder angle and thus the 243 die will not reach the full length of the neck to size down, the problem you have is no sizing die will bring the sharp shoulder ange on the 308 in line with the 243, it wont work,

the 308 would actually need to be "blown out" toprovide the contact necessary

buy some brass, it will save a lotof problems

Bob

 

[Cheechako]

308 has a sharper shoulder angle. . .

Say what???? The 308 and 243 have the same shoulder angle and location. The 243 case is about .030" longer in order to give it a more reasonable neck length.

Run a 308 into a 243 FL die. Thousands have been made that way. In fact, the original 243W was made from the 308W case way back in the early 1950s. There were a couple of 6mm wildcats (using the 308 case) that preceeded the factory cartridge. The original version of the 243 (240 Page) even preceeded the 308W.

Bob, where are you getting your information????

Ray

 

[TheBlueEyedBear]

I thought I would give that a try before I posted here. I greased up that .308 Win case real good then stuck it in the shellholder and closed the 243 FL die. Yep, crushed that piece of .308 brass real easy.

 

[Cheechako]

Blue

Are you saying that it didn't work???

All that you are doing is sizing the 308 neck down to 243. I've made hundreds of 243 cases that way without any problems whatsoever.

Try backing the die off and sizing only 1/3 to 1/2 of the neck. Then screw the die in and size the rest.

Ray

 

[TheBlueEyedBear]

Thanks Ray. I will give that a try.
Barry

 

[bheadboy]

cheecko, you ar right i was mistaken they both have 20%, the body length is shorter, my goof

apologies fellows

Bob

 

[TheBlueEyedBear]

No problem; No apology needed. Thanks for chiming in.
I'm going to try Ray's idea tomorrow to see if that cures the problem.

Barry

 

[HTSmith]

I've done a bunch. I use a 7mm08 die first. Loose about 1 out of every 50.

 

[lynn]

Barry
Like Ray said use a Full Length die!!!!! Not a seating die or neck bushing type die.
If you try it with a bushing type die you can only squeeze the necks down about 0.005 at a time meaning you'll need around 10 bushings at $17 a piece to getter dun.
Go to your local sporting goods store and get a straight 243 RCBS FULL LENGTH DIE and your all set.
Lynn

 

[jonbearman]

What neck thickness do you end up with when reforming as I used to ream the necks way back when before I just bought new brass.

 

[Rock Knocker]

Ive been wondering the same thing, kinda.

I was thinking about turning a bunch of Lake City 7.62 brass into 260 then fireforming to Ackley.

Any thoughts? My other two options are sticking with necking down Winchester 7-08 or spending the big bucks on some Lapua brass that just came out and fireforming that.

 

[navyrad8r]

Rock,
i used LC M80 (147 gr FMJ m14 food) to make .260 rem brass. and then turn the necks. i also did it in one step instead of the two step with 7-08 dies. The LC brass is so darn thick to start with, and then when you cruch it, it is hell to turn. but this is what i think... i got me some HEAVY duty brass!! case capacity is reduced but i am banking on that since i want to find a load that will allow me to use IMR4064/RL15/IMR4320/ TAC/ Varget etc. I have that stuff on hand and alot of .308 brass--match(m118), match (knurled with 168gr SMK), and M80.
Sorry service rifle shooter at birth, and aspiring Palma shooter at night. I am excited about the Lapua brass that hit the streets, but it is a bit too pricey right now, and with the new 21st century turner set up (not the lathe-yet) the expander and turning arbor are matched and made the chore like butter! i don't mind tuning brass. Oops i forgot to mention firing pin is bushed by gre-tan, wolf primers, 37gr of IMR4064, 31 inch 1:8 twist shilen, 142 SMK=2620, 140 Berger VLD=2650 jammed .010, no pressure signs. not much more progress yet but i am working on it.sorry to hijack the thread.
cheers,
doc

 

[Rustystud]

Over the last 35 years I converted a 55 gallon barrel full of 308 Lake City Match brass to 243 Winchesters to shoot Prarrie Dogs.
It can be done but may require the necks to be turned just to clean them up.
I wore out two sizing dies doing it. This was years ago and at the time LEE made the only solid decapper that was tapered on both ends. You would be wise to anneal and use plenty of lube bot inside and out.
I left about 4000 spent pieces in little plies in a prarrie dog town just north of Garden City Kansas. In two weeks I also shot 8000 rounds of lake city 223 with 50 grain SX Hornady bullets 5000 rounds of 22 Rimfire Zappers. What a great time we had.
Nat Lambeth

 

[Rock Knocker]

Thanks for the help.

 

[Cheechako]

243W brass made from 308W could actually improve things if you're shooting a factory rifle. A loaded round using LC 63 GI brass reformed to .243 measures about .274" at the neck. A factory R-P .243 usually measures about .272". SAAMI specs call for a minimum chamber of .277" and a maximum cartridge of .276".

I don't bother turning the necks on my reformed brass, not even to clean them up. They are more than good enough for live varmint shooting exactly the way they come out the die.

If you are shooting a custom chamber you'll probably have to turn the necks regardless.

Ray

 

[Clark]

This is Lake City [LC] 308 brass I necked down to 243.
I did not turn the necks.
They are all the same load.
Some necks pinch the bullets more than others.

 

[jonbearman]

Clark are you trying to tell us something?

 

[expiper]

Hi Clark...what kind of rifle were those ctgs. fired in ...the square ejector has me puzzled.....???,,,Roger

 

[Cheechako]

Clark

I have a bigger question. Why are there two of the blown cases??? After the first one, did you not realize something was wrong? Bad wrong! That loud noise you heard was your rifle screaming, "STOP! Don't do that again!"

And, if it was really a situation where the neck was "pinching" the bullet enough to raise pressure to a destructive level, did you not notice difficulty in chambering?

There are a lot of things that do not add up.

Ray