case length for 22-243

doubletapp23 · August 17, 2018, 01:36 PM

Just bought a remington 700 in 22-243. It came with a set of rcbs dies. I'm forming my own brass from new 243 win hornady cases. Do I need to trim the cases or is the original 243 win case length correct? What length should I trim them to? Thanks for the help.

Dufus · August 17, 2018, 02:13 PM

From what I have, trim length is 2.035".

mkl · August 17, 2018, 02:15 PM

I'm not an expert on wildcats, but I would think you would need to inside neck ream the .243 cases after they have been sized down to allow a .223 bullet to fit. Seems to me that the brass neck would be too thick otherwise.

Others will have to answer your question as to proper OAL of the case as I have no experience with this cartridge.

Be careful what bullets you use. I've heard that many of the polymer tip bullets melt from air friction at the velocity you are probably getting in that caliber and a melting tip will cause a loss of accuracy.

**Unclenick** · August 17, 2018, 03:18 PM

Doubletapp23,

Welcome to the forum.

The best thing would be to make a chamber cast and use a number 0.010" shorter than the chamber mouth from the shoulder as the maximum and 0.020" shorter than the chamber mouth from the shoulder as the trim-to number. QuickLOAD's database puts the maximum at 2.018".

GWS · August 18, 2018, 12:09 AM

Doubletapp23,

I came into a .22-243 quite by accident. It was abandoned in one of my selfstorage units. It came in a canvas zippered gun case with a pocket that had a box of reloads in it. I thought I had a .243 until I looked closer.

The reloads were .22-243 Winchester which has the same shoulder angle as the .243 Winchester........so I thought that's what I had.

The rifle was obviously someones unfinished project made from an FN Mauser. I took someone's advice to do a chamber cast, and found that the barrel was not the vanilla 22-243 Winchester matching the reloads, but .22-243 Middlestead, which has a steeper shoulder.

I tell you this because Uncle Nick has given you good advice to do a chamber cast to make sure of what you got.....as well as give you data on case length. You might have a Middlestead version too, as they are more common and popular......and you can't tell without a chamber cast......or you could shoot reloads made with your die set and take the chance of it fire forming well.

Which dies came with it Winchester or Middlestead? I ordered Winchester dies and luckily Grafs exchanged them for Middlestead.

There are a few sources of information on loads on the internet. Few is the governing word there. Good luck with your project.

http://www.ballisticstudies.com/Know...e/.22-243.html

I found some info on Okshooters.com thread 168954.

Greybeards forum:
http://www.gos2gbo.com/forums/index.php/board,91.0.html

http://www.accuratereloading.com/22-243.html

BTW, the barrel on my project was chambered specifically so that reaming inside the .243 case necks is not necessary......that depends on the smith who chambered it. The chamber cast should help you determine that also.

I ordered low-melt Alloy 4250-2 from Bolton Metal Products. to cast my chamber.

doubletapp23 · August 18, 2018, 08:57 AM

Thanks for all the information. My rifle has a shilen barrel and came with RCBS dies in 22-243 win. A chamber cast is probaly the way I'll go. Thanks again

August 17, 2018, 01:36 PM	#1
doubletapp23 Junior Member Join Date: August 16, 2018 Posts: 2	case length for 22-243 Just bought a remington 700 in 22-243. It came with a set of rcbs dies. I'm forming my own brass from new 243 win hornady cases. Do I need to trim the cases or is the original 243 win case length correct? What length should I trim them to? Thanks for the help.

August 17, 2018, 03:18 PM	#4
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Doubletapp23, Welcome to the forum. The best thing would be to make a chamber cast and use a number 0.010" shorter than the chamber mouth from the shoulder as the maximum and 0.020" shorter than the chamber mouth from the shoulder as the trim-to number. QuickLOAD's database puts the maximum at 2.018". __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

August 18, 2018, 12:09 AM	#5
GWS Senior Member Join Date: September 8, 2010 Location: New Mexico Posts: 688	Doubletapp23, I came into a .22-243 quite by accident. It was abandoned in one of my selfstorage units. It came in a canvas zippered gun case with a pocket that had a box of reloads in it. I thought I had a .243 until I looked closer. The reloads were .22-243 Winchester which has the same shoulder angle as the .243 Winchester........so I thought that's what I had. The rifle was obviously someones unfinished project made from an FN Mauser. I took someone's advice to do a chamber cast, and found that the barrel was not the vanilla 22-243 Winchester matching the reloads, but .22-243 Middlestead, which has a steeper shoulder. I tell you this because Uncle Nick has given you good advice to do a chamber cast to make sure of what you got.....as well as give you data on case length. You might have a Middlestead version too, as they are more common and popular......and you can't tell without a chamber cast......or you could shoot reloads made with your die set and take the chance of it fire forming well. Which dies came with it Winchester or Middlestead? I ordered Winchester dies and luckily Grafs exchanged them for Middlestead. There are a few sources of information on loads on the internet. Few is the governing word there. Good luck with your project. http://www.ballisticstudies.com/Know...e/.22-243.html I found some info on Okshooters.com thread 168954. Greybeards forum: http://www.gos2gbo.com/forums/index.php/board,91.0.html http://www.accuratereloading.com/22-243.html BTW, the barrel on my project was chambered specifically so that reaming inside the .243 case necks is not necessary......that depends on the smith who chambered it. The chamber cast should help you determine that also. I ordered low-melt Alloy 4250-2 from Bolton Metal Products. to cast my chamber. Last edited by GWS; August 18, 2018 at 12:38 AM.

August 17, 2018, 02:13 PM	#2
Dufus Senior Member Join Date: December 10, 2014 Posts: 1,965	From what I have, trim length is 2.035".

August 17, 2018, 02:15 PM	#3
mkl Senior Member Join Date: April 25, 2008 Location: DFW area, Texas Posts: 494	I'm not an expert on wildcats, but I would think you would need to inside neck ream the .243 cases after they have been sized down to allow a .223 bullet to fit. Seems to me that the brass neck would be too thick otherwise. Others will have to answer your question as to proper OAL of the case as I have no experience with this cartridge. Be careful what bullets you use. I've heard that many of the polymer tip bullets melt from air friction at the velocity you are probably getting in that caliber and a melting tip will cause a loss of accuracy.

August 18, 2018, 08:57 AM	#6
doubletapp23 Junior Member Join Date: August 16, 2018 Posts: 2	Thanks for all the information. My rifle has a shilen barrel and came with RCBS dies in 22-243 win. A chamber cast is probaly the way I'll go. Thanks again