Cortina expander die 284

[Phys86]

I've been looking at Cortina's 284 expander die for getting better sizing near the base of my 284 brass.

I'm wondering what measurements others are seeing on their brass pre and post sizing that are using it.

 

[Leeman]

I'm getting sizing down to .4995 which is less than the .497 they claimed but maybe down to the brass which is lapua. The fired case measures .5005 so a bit of a tight chamber obviously. It does seem to make a slight improvement in bolt manipulation but not as much as I had hoped for.

 

[Phys86]

I'm getting sizing down to .4995 which is less than the .497 they claimed but maybe down to the brass which is lapua. The fired case measures .5005 so a bit of a tight chamber obviously. It does seem to make a slight improvement in bolt manipulation but not as much as I had hoped for.

Where did they say 0.497?

That seems mighty small

 

[Leeman]

Some dude called Clay when I emailed about the size of the die, came back with that dimension. I expected some spring back of course but thought I would get a bit smaller size that what I am measuring. Maybe depends on the amount of times fired and initial dimensions prior to sizing?

 

[Dan-Schenk]

Some dude called Clay when I emailed about the size of the die, came back with that dimension. I expected some spring back of course but thought I would get a bit smaller size that what I am measuring. Maybe depends on the amount of times fired and initial dimensions prior to sizing?

Try double stroking it.

 

[Leeman]

Try double stroking it.

Tried that, plus rotating 90 & 180 without any difference.

 

[jnm300ultra]

This is another suggestion is a small base die. I have to use it on my 284 Norma brass. It’s been shoot probably 5-6 times and now I use it every other time. I didn’t want to go to another reloading step but I didn’t want to get a new barrel or new brass. Next time I will have my own reamer made. I also have Widden dies and a Redding small base die. I believe the reamer that cut my chamber was for a Lapua 6.5x284 and to neck up to 284.
Good luck with your dies.
Jason

 

[Phys86]

Does anyone have any knowledge on how long the backorder for the 284 version is? I have sent an email but haven't heard anything back from them.

 

[Phys86]

I have one of these on the way.

For you that have used it, have you noticed it changing your shoulder bump if you use it after sizing? Would it be better to use it before the FL sizing die?

 

[Leeman]

I have one of these on the way.

For you that have used it, have you noticed it changing your shoulder bump if you use it after sizing? Would it be better to use it before the FL sizing die?

I was using if before sizing, didn't change shoulder bump

 

[Phys86]

Thanks! I'm excited to see if it helps out w my Peterson brass that has quite a few firings. I'll report back with some measurements.

 

[Dave M.]

I'm getting sizing down to .4995 which is less than the .497 they claimed but maybe down to the brass which is lapua. The fired case measures .5005 so a bit of a tight chamber obviously. It does seem to make a slight improvement in bolt manipulation but not as much as I had hoped for.

.4995 is GREATER THAN .497

 

[Phys86]

.4995 is GREATER THAN .497

I think he means less sizing is happening

 

[Phys86]

I could have swore I replied back here after I received the die I bought.

I tested the expander die body (no expander) on a piece of my Lapua that I've shot from my 30-284ai. The web measured 0.502 after firing and 0.501 after running it through my FL die. The EC expander die body took it all the way back to 0.499!

However, it will not work for a 30,cal neck even though it states in the description it can be used for all 284win variants.

It destroyed my case by peeling the neck down like a banana. After the EC die, the neck OD was 0.331.

I've tried contacting EC many times since to return it or have him open the neck, left voicemail, sent email, and haven't heard back.

Anyone know how to contact him?

 

[ern.santos]

might want to wait for him to get back from shooting the SWN in AZ

 

[Phys86]

might want to wait for him to get back from shooting the SWN in AZ

I don't know his schedule, but I figured he'd have someone managing the phone and emails I'd he was away. Is he completely a 1 man operation?

 

[Leeman]

I think he means less sizing is happening

Exactly, less sizing than I was expecting based on contacting the manufacturer for the specification of the die

 

[Phys86]

Talked to them on the phone today and got the die sent back. They're going to open the neck for me.

 

[Phys86]

Got it back today. I ran one of my fired brass through the die which measured 0.503 at the web. After sizing, it measured 0.500. job well done! However, it did lengthen base to shoulder by 0.001.

I'm guessing that after I start using it each cycle, it won't be squeezed all the way from 0.503 to 0.500, so it won't move the shoulder nearly as much.