Good day all, I posted a while back asking if anyone made 9mm Largo brass from .223.
Well after some searching online and consulting all my reloading manuals, making many drawings, some test loads and a post In a different thread. I feel I can post what I have found and what has worked for me. I do understand that using 223 brass does have some limitations and care is needed not to load to extreme velocity and pressure.
So here is what I have done.
First I selected some brass of different manufacturers. Rem, federal, win, pmp, and some 5.56 LC and cut them to 23mm on length.
I then tried to use a standard 9mm RCBS die to open the case mouth with a new punch and bell the end. But it did not work. Because it was trying to move too much material, and the ID of the RCBS die was too big. One side of the brass bulge. I could get a few to work, but I needed a better solution. So made some dies.
The ID of a cut 223 case is .320 to .330. I made a punch to use in an old RCBS A2 press. It measures .340 It just starts moving the brass out. I used a 223 shell holder and it works well.
Next I made a die that its ID is .388 and a punch that is .355. With these two punches and die it prepared the brass to be able to use a standard 9mm expansion die to open the case mouth. To accept a bullet.
Using published reloading data for a cast lead 115 gr bullet. I decreased the minimum charge by 10% to start. I loaded some up with a Berrys 115gr 9mm. Then off to the range. After some adjustment to the powder charge. I have a load that works.
I made a case gage as close to 9mm Largo as I could to check each loaded bullet. I did learn that 5.56 brass is too thick to use As is Fereral and PMP. Remington and Winchester are the easiest to work with and that is what I am using.
The loaded ammunition works well for me and my 400. The velocity is 1100fps and the pistol cycles them and locks open on the last shot.
And they are accurate.
Now I know there will be some who say just buy starline 38 supper brass. Yes yes. And some will caution that the base of a 223 is too small and the case volume of the 223 is not the same as the 9mm Largo. I understand that and have taken it in to my reloading.
This was a fun and educational project for me. This might not be for everyone.
Sorry I will not list the powder and weight I used.
Well after some searching online and consulting all my reloading manuals, making many drawings, some test loads and a post In a different thread. I feel I can post what I have found and what has worked for me. I do understand that using 223 brass does have some limitations and care is needed not to load to extreme velocity and pressure.
So here is what I have done.
First I selected some brass of different manufacturers. Rem, federal, win, pmp, and some 5.56 LC and cut them to 23mm on length.
I then tried to use a standard 9mm RCBS die to open the case mouth with a new punch and bell the end. But it did not work. Because it was trying to move too much material, and the ID of the RCBS die was too big. One side of the brass bulge. I could get a few to work, but I needed a better solution. So made some dies.
The ID of a cut 223 case is .320 to .330. I made a punch to use in an old RCBS A2 press. It measures .340 It just starts moving the brass out. I used a 223 shell holder and it works well.
Next I made a die that its ID is .388 and a punch that is .355. With these two punches and die it prepared the brass to be able to use a standard 9mm expansion die to open the case mouth. To accept a bullet.
Using published reloading data for a cast lead 115 gr bullet. I decreased the minimum charge by 10% to start. I loaded some up with a Berrys 115gr 9mm. Then off to the range. After some adjustment to the powder charge. I have a load that works.
I made a case gage as close to 9mm Largo as I could to check each loaded bullet. I did learn that 5.56 brass is too thick to use As is Fereral and PMP. Remington and Winchester are the easiest to work with and that is what I am using.
The loaded ammunition works well for me and my 400. The velocity is 1100fps and the pistol cycles them and locks open on the last shot.
And they are accurate.
Now I know there will be some who say just buy starline 38 supper brass. Yes yes. And some will caution that the base of a 223 is too small and the case volume of the 223 is not the same as the 9mm Largo. I understand that and have taken it in to my reloading.
This was a fun and educational project for me. This might not be for everyone.
Sorry I will not list the powder and weight I used.
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