.243 Win CASES FROM .308 ??

tom234 · September 15, 2009, 07:28 PM

How difficult is it to make .243 Win cases from .308 NATO and/or commercial brass ? What's the process and what equipment do I need ? I already reload .243 Win.

SL1 · September 15, 2009, 08:10 PM

I'll start by saying that I have not done it. The .243 case is 0.030" shorter than the .308, but it may lengthen some when necked-down. I don't think it would matter much. But necking down the case will make its neck thicker. If it gets too thick for your chamber neck, it will not be able to release the bullet and pressure will go way up. So, you need to either (1) make a cast of your chamber and measure the diameter and, if necessary, turn the necks down to allow at least 0.002" of clearance, or (2) just turn the necks down to the thickness of commercial .243 brass. If you use thicker necks in a commercial chamber, you might be able to achieve a little more accuracy, but that isn't a sure thing.

Others may come on here and tell you if you need to neck down in steps, say to 7mm or 6.5 mm and then to 6mm (.243"). I effectively neck down .30-30 cases from about .40 caliber to .308 in one step when I shorten the case to make .30 Herrett, and I do that in one step. Then I check necks and clean-up any dimensional problems and then anneal the case necks. They seem to last a long time if I don't use hot loads that stretch the case in the springy Contender action. But, if I do that, they fail in the web area first, not in the neck, so it isn't due to the neck reduction.

SL1

PCJim · September 15, 2009, 08:49 PM

Why not try to trade the .308 off for an equivalent amount of .243? While resizing .308 to .243 can be done, unless you just don't have any other project to do, it is probably much more of a hassle than it's worth. .243 brass is much too common. If you were wanting to convert into a more rare caliber, then I'd say go for it.

David Wile · September 15, 2009, 09:13 PM

Hey Tom,

I have two boxes of .243 brass I am trying to trade. One box has 17 Win cases and 4 PMC cases. The other box has 20 rounds of Federal brass. All of the brass is in quite good condition. About the only brass I really can use anymore is 45-70 and perhaps some more 10mm. If you have any of that brass to trade, let me know. If you do not have any of the brass I need, I would be happy to just give you the .243 brass for the $5 it costs to ship them by USPS Priority Mail. Let me know if you are interested.

Best wishes,
Dave Wile

Willis · September 15, 2009, 09:54 PM

Several years ago I did a couple hundred of them. All you have to do is lube the brass getting the neck as well. Send the 308 into a 243 resizing die about 1/16 inch and pull it out, then send it in another 1/16 and out. You do this until it goes all the way in. You might have to relube the neck acouple of times through the process. I did the relube by putting lube on my fingers and just reaching in while the brass was still in the press. Never push it in real hard, just enough to move it in a bit each stroke. It will only take 4 to 6 strokes for each piece of brass. It does not take long to do a hundred. That being said, now that I have these 243's that say 308 on the bottom of the brass I HATE THEM. I didn't have a 308 at the time I did the resizing. Now it is a problem because I let my wife use my 243 for deer and a 308 for elk. I always check her ammo before she goes out. Even if I throw out all of the 243's marked 308 I can never be sure there is not one more around the gun room. I am not reloading them anymore. I don't really think any damage would be done if a 243 went down the 308, but then who wants to take the chance. I would get 243 brass.

Good Luck
Willis

tom234 · September 16, 2009, 12:33 PM

Thanks guys. I think it may be more work and/or trouble than it's worth. I probably should just bite the bullet and buy new .243 brass or look for some at a gun show. I have picked up some .243 brass at the local range but not enough to be worth while.

Dr. Strangelove · September 16, 2009, 12:58 PM

Here in GA it's the beginning of deer season and the ranges are full of non-reloaders sighting in rifles with factory ammo. I get bunches of once fired brass this way, most guys even box it back up and hand it to me as they leave.

James R. Burke · September 17, 2009, 06:13 PM

I agree with PCJIM, try getting the .243 brass. It is pretty common and so is the .308 should be able to make a trade real easy. But you might be doing it just for the fun of the project in that case I cant help you any. I do have both calibers, and just get the brass I need.

Clark · September 18, 2009, 02:21 PM

I have necked 308 down to 243.

It is tempting if you have thousands of pieces of 308, and feel too cheap to buy 243 brass, but I don't recommend it. Sure it can be done.

With pin gauges, measure the neck of your chamber.
With a dial indicator, set the dial to read that pin correctly.
Then measure the loaded 243 rounds made with 308 brass.
At the base of the neck, it will often be too tight.

Can you see pressure signs in the above brass from my 1938 Turk Mauser with 308 brass necked down to 243?
They all three had the same load.

A little bullet pinch in the chamber goes a long way toward increasing the pressure.

SnapDaddy · October 24, 2009, 11:37 AM

Just joint forum and saw this thread. Thought I would throw in my 2 cents. From what I understand, if you resize from 308 to 243, you will need to turn the neck down to the correct wall thickness. Otherwise, you will get what clark experienced.

September 15, 2009, 07:28 PM	#1
tom234 Senior Member Join Date: February 14, 2008 Location: Kansas Posts: 753	.243 Win CASES FROM .308 ?? How difficult is it to make .243 Win cases from .308 NATO and/or commercial brass ? What's the process and what equipment do I need ? I already reload .243 Win.

September 15, 2009, 09:54 PM	#5
Willis Member Join Date: June 14, 2005 Location: Montana Posts: 37	308 to 243 Several years ago I did a couple hundred of them. All you have to do is lube the brass getting the neck as well. Send the 308 into a 243 resizing die about 1/16 inch and pull it out, then send it in another 1/16 and out. You do this until it goes all the way in. You might have to relube the neck acouple of times through the process. I did the relube by putting lube on my fingers and just reaching in while the brass was still in the press. Never push it in real hard, just enough to move it in a bit each stroke. It will only take 4 to 6 strokes for each piece of brass. It does not take long to do a hundred. That being said, now that I have these 243's that say 308 on the bottom of the brass I HATE THEM. I didn't have a 308 at the time I did the resizing. Now it is a problem because I let my wife use my 243 for deer and a 308 for elk. I always check her ammo before she goes out. Even if I throw out all of the 243's marked 308 I can never be sure there is not one more around the gun room. I am not reloading them anymore. I don't really think any damage would be done if a 243 went down the 308, but then who wants to take the chance. I would get 243 brass. Good Luck Willis

September 15, 2009, 08:10 PM	#2
SL1 Senior Member Join Date: November 8, 2007 Posts: 2,001	I'll start by saying that I have not done it. The .243 case is 0.030" shorter than the .308, but it may lengthen some when necked-down. I don't think it would matter much. But necking down the case will make its neck thicker. If it gets too thick for your chamber neck, it will not be able to release the bullet and pressure will go way up. So, you need to either (1) make a cast of your chamber and measure the diameter and, if necessary, turn the necks down to allow at least 0.002" of clearance, or (2) just turn the necks down to the thickness of commercial .243 brass. If you use thicker necks in a commercial chamber, you might be able to achieve a little more accuracy, but that isn't a sure thing. Others may come on here and tell you if you need to neck down in steps, say to 7mm or 6.5 mm and then to 6mm (.243"). I effectively neck down .30-30 cases from about .40 caliber to .308 in one step when I shorten the case to make .30 Herrett, and I do that in one step. Then I check necks and clean-up any dimensional problems and then anneal the case necks. They seem to last a long time if I don't use hot loads that stretch the case in the springy Contender action. But, if I do that, they fail in the web area first, not in the neck, so it isn't due to the neck reduction. SL1

September 15, 2009, 08:49 PM	#3
PCJim Senior Member Join Date: July 11, 2008 Location: FL Posts: 570	Why not try to trade the .308 off for an equivalent amount of .243? While resizing .308 to .243 can be done, unless you just don't have any other project to do, it is probably much more of a hassle than it's worth. .243 brass is much too common. If you were wanting to convert into a more rare caliber, then I'd say go for it.

September 15, 2009, 09:13 PM	#4
David Wile Senior Member Join Date: June 14, 2001 Location: Mechanicsburg, PA Posts: 585	Hey Tom, I have two boxes of .243 brass I am trying to trade. One box has 17 Win cases and 4 PMC cases. The other box has 20 rounds of Federal brass. All of the brass is in quite good condition. About the only brass I really can use anymore is 45-70 and perhaps some more 10mm. If you have any of that brass to trade, let me know. If you do not have any of the brass I need, I would be happy to just give you the .243 brass for the $5 it costs to ship them by USPS Priority Mail. Let me know if you are interested. Best wishes, Dave Wile

September 16, 2009, 12:33 PM	#6
tom234 Senior Member Join Date: February 14, 2008 Location: Kansas Posts: 753	Thanks guys. I think it may be more work and/or trouble than it's worth. I probably should just bite the bullet and buy new .243 brass or look for some at a gun show. I have picked up some .243 brass at the local range but not enough to be worth while.

September 16, 2009, 12:58 PM	#7
Dr. Strangelove Senior Member Join Date: August 1, 2008 Location: Athens, GA Posts: 1,436	Here in GA it's the beginning of deer season and the ranges are full of non-reloaders sighting in rifles with factory ammo. I get bunches of once fired brass this way, most guys even box it back up and hand it to me as they leave.

September 17, 2009, 06:13 PM	#8
James R. Burke Senior Member Join Date: January 3, 2009 Location: U.P. of Mich/Quinnesec Posts: 1,897	I agree with PCJIM, try getting the .243 brass. It is pretty common and so is the .308 should be able to make a trade real easy. But you might be doing it just for the fun of the project in that case I cant help you any. I do have both calibers, and just get the brass I need.

September 18, 2009, 02:21 PM	#9
Clark Senior Member Join Date: December 4, 1999 Location: WA, the ever blue state Posts: 4,678	I have necked 308 down to 243. It is tempting if you have thousands of pieces of 308, and feel too cheap to buy 243 brass, but I don't recommend it. Sure it can be done. With pin gauges, measure the neck of your chamber. With a dial indicator, set the dial to read that pin correctly. Then measure the loaded 243 rounds made with 308 brass. At the base of the neck, it will often be too tight. Can you see pressure signs in the above brass from my 1938 Turk Mauser with 308 brass necked down to 243? They all three had the same load. A little bullet pinch in the chamber goes a long way toward increasing the pressure.

October 24, 2009, 11:37 AM	#10
SnapDaddy Junior Member Join Date: October 24, 2009 Posts: 1	Just joint forum and saw this thread. Thought I would throw in my 2 cents. From what I understand, if you resize from 308 to 243, you will need to turn the neck down to the correct wall thickness. Otherwise, you will get what clark experienced.