Neck Sizing 243 brass to 7mm-08

roc1 · December 8, 2009, 10:18 PM

I have sized 308 brass to my 7mm-08 with no problems. I also have and abundance of 243 brass and was wondering what problems if any would be caused by necking 243 back to 7-08? This would save buying 7-08 cases. Do you have turn necks or anything else?
Thanks
roc1

Shoney · December 8, 2009, 11:32 PM

Necking 243 up to 7-08
The problem I see is that the neck will be very thin. It may not hold the bullet with enough neck tension

smleno1mkIII · December 8, 2009, 11:47 PM

It works I've done it I've also necked up .243 brass to .308 no problems.

roc1 · December 9, 2009, 07:25 AM

Did you just run the 243 brass through the 7-08 full length size die?
Thanks
roc1

**Unclenick** · December 9, 2009, 10:46 AM

It should take about 0.002" off the neck wall. Still within SAAMI limits if you start with neck walls at least 0.012" thick. It will be a little more prone to splitting, so annealing is a good idea. The best way I've found to do this is get a Sinclair die body for neck turning mandrels and use their undersize mandrels for neck expansion. The long taper of the mandrels eases the brass in. Use a good case lube on the inside of the neck when doing this. If you get shoulder buckling, you may need to go in a couple of steps, with a .264 mandrel as the intermediate size.

smleno1mkIII · December 12, 2009, 11:59 PM

yes I did

December 8, 2009, 10:18 PM	#1
roc1 Senior Member Join Date: July 31, 2005 Location: Lubbock Texas Posts: 560	Neck Sizing 243 brass to 7mm-08 I have sized 308 brass to my 7mm-08 with no problems. I also have and abundance of 243 brass and was wondering what problems if any would be caused by necking 243 back to 7-08? This would save buying 7-08 cases. Do you have turn necks or anything else? Thanks roc1

December 8, 2009, 11:32 PM	#2
Shoney Senior Member Join Date: February 21, 2002 Location: Transplanted from Montana Posts: 2,311	Necking 243 up to 7-08 The problem I see is that the neck will be very thin. It may not hold the bullet with enough neck tension __________________ I pledge allegiance to the Flag - - -, and to the Republic for which it stands….Our Forefathers were brilliant for giving us a Republic, not a democracy! Do you know the difference??? and WHY?http://www.wallbuilders.com/LIBissue...les.asp?id=111

December 9, 2009, 10:46 AM	#5
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	It should take about 0.002" off the neck wall. Still within SAAMI limits if you start with neck walls at least 0.012" thick. It will be a little more prone to splitting, so annealing is a good idea. The best way I've found to do this is get a Sinclair die body for neck turning mandrels and use their undersize mandrels for neck expansion. The long taper of the mandrels eases the brass in. Use a good case lube on the inside of the neck when doing this. If you get shoulder buckling, you may need to go in a couple of steps, with a .264 mandrel as the intermediate size. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

December 8, 2009, 11:47 PM	#3
smleno1mkIII Senior Member Join Date: November 5, 2009 Location: washington state Posts: 176	It works I've done it I've also necked up .243 brass to .308 no problems.

December 9, 2009, 07:25 AM	#4
roc1 Senior Member Join Date: July 31, 2005 Location: Lubbock Texas Posts: 560	Did you just run the 243 brass through the 7-08 full length size die? Thanks roc1

December 12, 2009, 11:59 PM	#6
smleno1mkIII Senior Member Join Date: November 5, 2009 Location: washington state Posts: 176	yes I did