Making 338 Rum brass

[can1010]

one of my wildcats push the shoulder back so the neck shoulder junction is the same as 300 win mag. had smith cut off bottom of 375 rum die and use that first then use 338 rum die and your done. lots of lube go slow.

 

[338RUML]

one of my wildcats push the shoulder back so the neck shoulder junction is the same as 300 win mag. had smith cut off bottom of 375 rum die and use that first then use 338 rum die and your done. lots of lube go slow.

Ok is there any special die I could buy to help this process instead of just shoving a 300 into my 338 sizer? Or is it okay to do it will plenty of imperial sizing wax? Or a lubricant of some kind, >>Bottom line gentlemen is it worth it?<< does it make a perfect case or does it basically need to be fire formed to be exact?

 

[can1010]

have a smith cut bottom off 375 rum size die pull out expander and use first. makes it easier on brass and press. or use your 338 rum die and use 4 or 5 strokes little at a time. don't try to do it in one hard stroke. trim and shoot no fireforming needed

 

[Rich Coyle]

If you get your head space correct they come out really close to fireformed shape. I full length size mine because it is a bushing die and it's the only 6.5 this size.

 

[Bravo 4]

Ok is there any special die I could buy to help this process instead of just shoving a 300 into my 338 sizer? Or is it okay to do it will plenty of imperial sizing wax? Or a lubricant of some kind, >>Bottom line gentlemen is it worth it?<< does it make a perfect case or does it basically need to be fire formed to be exact?

Now I just lube and "shove" it in my .338 RUM die. It doesn't make a 100% perfect case as I can tell the shoulder is slightly rounded compared to a fired case (the shoulder is just a little sharper). However I haven't seen a real difference in performance.

 

[Predator 22]

Do you get donuts? I've read the hole thread and nobody has mentioned if they are having to turn the necks from pushing the neck shoulder junction back. Don't have a rum just curious.

 

[Bravo 4]

Do you get donuts? I've read the hole thread and nobody has mentioned if they are having to turn the necks from pushing the neck shoulder junction back. Don't have a rum just curious.

No Sir, I do not get donuts.

 

[338RUML]

have a smith cut bottom off 375 rum size die pull out expander and use first. makes it easier on brass and press. or use your 338 rum die and use 4 or 5 strokes little at a time. don't try to do it in one hard stroke. trim and shoot no fireforming needed

Is the 375 shorter than the 300? I thought both were 2.850" how would this help? I'm having a senior moment I'm sure, how much do you cut off the bottom of it?

 

[Rich Coyle]

have a smith cut bottom off 375 rum size die pull out expander and use first. makes it easier on brass and press. or use your 338 rum die and use 4 or 5 strokes little at a time. don't try to do it in one hard stroke. trim and shoot no fireforming needed

I didn't read your post carefully. That is a good idea.

 

[can1010]

take .090 off the 375 die. take out expander size brass will push back most of shoulder. finish with 338 die. done in 2 steps is easier on case

 

[can1010]

I didn't read your post carefully. That is a good idea.

works great on my wildcat. I am pushing it back .188 think fat 300 win mag with long neck and 40 degree shoulder

 

[338RUML]

take .090 off the 375 die. take out expander size brass will push back most of shoulder. finish with 338 die. done in 2 steps is easier on case

I knew I was having a senior moment!!! Finally clicked! Thanks gentlemen

 

[338RUML]

Tried to use 7 ultra to 338 ultra with just my 338 sizer die went pretty smooth till the very end (went in and out slowly probably 100 times through the whole prcess) so anyway towards the very end I thought I was safe to send the press to the top of the stroke (about 2-3 inches so I sent it all the way somewhat fast and dimpled the neck shoulder junction I will attach a pic if I can figure it out. So I'm assuming it's because I went a little fast at the end. You can use 7mm ultra brass to make 338 ultra also right? (That's all I had on hand was 7 no 300). Or is 7mm just a little to small to do it? Thanks

Well I don't know how to attach a pic sorry, it's just typical dumpling at the neck shoulder junction

 

[Bravo 4]

I've used 7 RUM brass to make .338 Edge and RUM. I do anneal it first.