Sizing 380 with .223 small base

[Tony k]

My Lee .380 sizer die is probably the first Lee product I've been disappointed with. I was unable to get acceptable neck tension with it. I started researching solutions and discovered 2 things:

1. Many people have the same problem with the Lee 380 sizer die. They often solve the problem by getting the undersize die, which is .004" smaller.
2. Some people size 380 with a 223 rem die.

I've got an rcbs small base 223 die set, and so far I've been able to solve my 380 neck tension problems with it.

I measured the I.D. of both dies using mitutoyo calipers (not pin guages) and found that the Lee 380 sizer is .366" and the 223 rem SB is .364”. That .002" makes all the difference in the world when it comes to erratic performance and incomplete powder burn.

I'm going to get a new sizer for 380 because I like the convenience of the carbide, but I question the need to get the Lee 380 undersize die.

Does anyone have an RCBS, Hornady, or other 380 sizer die, and do you know it's inside diameter?

 

[Toprudder]

Don't know the inside diameter, I've never measured it, but I've never had a problem with neck tension on my 380 loads using the Dillon die set.

 

[edwardware]

I've got an rcbs small base 223 die set, and so far I've been able to solve my 380 neck tension problems with it.

Innovative, I like it!

I suspect either a bad die, or your bullets are undersized.

I've found Lee's willingness to help a bit lacking (or maybe I'm spoiled by RCBS and Hornady), but you should definitely call and give them a chance to make it right.

 

[Tony k]

Innovative, I like it!

I suspect either a bad die, or your bullets are undersized.

I've found Lee's willingness to help a bit lacking (or maybe I'm spoiled by RCBS and Hornady), but you should definitely call and give them a chance to make it right.

Bullet size is right on the money @.355". I've also used .356" Berry's bullets with slightly less issue (but still not great).

I don't know what the id of the die is supposed to be, but you are right that I should call Lee

 

[Walkalong]

On my RCBS .380 sizer (bought probably 30 years ago) the .366 pin gauge will pass, and the .367 will not. I get excellent neck tension with my RCBS .380 dies set.

 

[Tony k]

On my RCBS .380 sizer (bought probably 30 years ago) the .366 pin gauge will pass, and the .367 will not. I get excellent neck tension with my RCBS .380 dies set.

Hmmm... I was expecting other brands might be smaller.

I emailed Lee today. They were prompt and responsive. They suggested I try the undersize die. It's only like $25, I guess I will.

 

[Walkalong]

How did you measure the ID?

 

[Tony k]

Good point. I used Calipers. RCBS and mitutoyo. So with a pin it might be a thou or two bigger

 

[Walkalong]

Buy an RCBS sizer and be happy.

It's a shame they are nearly the price of the die set.

 

[rskent]

My Lee .380 sizer die is probably the first Lee product I've been disappointed with. I was unable to get acceptable neck tension with it.

So, do you think it is an inconsistency with the die or the brass. What I am asking is, was the die manufactured with too big of a hole in it? If so, what does Lee have to say about it?

 

[Blue68f100]

What brand brass are you using? RP is know to be some and thin which will cause problems.

It seams Lee has a problem holding tolerance on there products, way more so than all others. I would suggest going with a RCBS or other brand. Since Lee things nothing is wrong with their sizing die.

 

[Tony k]

So, do you think it is an inconsistency with the die or the brass. What I am asking is, was the die manufactured with too big of a hole in it? If so, what does Lee have to say about it?

I'm leaning towards the die being the culprit. I say that only after switching to the 223 sizing die and having all my supposed brass related problems completely disappear.

Regarding the die's actual i.d., that's why I was asking you all about your .380 sizer die specs because I suspect mine is too big. Apparently, Lee thinks my die is fine because they suggested I get an undersize sizer. I think their specs might need to be modified.

My .366" sizer produces .369" brass pretty consistantly. I suspect that's insufficient.

 

[Tony k]

What brand brass are you using? RP is know to be some and thin which will cause problems.

It seams Lee has a problem holding tolerance on there products, way more so than all others. I would suggest going with a RCBS or other brand. Since Lee things nothing is wrong with their sizing die.

I'm using all different kinds of brass, but RP is a minor constituent of my mix. I agree with your general assessment of the brass though. Specific to 380, I haven't noticed that it produces results much different than most others.

As far as Lee's quality control, yeah, I was actually hoping they would tell me my die was out of spec and that they would send a new one. But after I told them my die's inside diameter, and the outside diameter of my sized brass, they just suggested I try the undersize die.

The standard Lee 380 sizing die producing insufficient neck tension seems to be a consistent theme in my interwebs research. The question is, where do the other manufacturers fall? I'm pretty sure the undersize die will solve the problem, but where does undersizing by .004" according to Lee's standard fall within the rest of the industry?

 

[rskent]

Tony

My Lee .380acp sizer is .367” It works fine for me. I have not had any problems yet.

I do have one of their U dies for .32acp. I helped with sizing problems with different manufactures of brass.

 

[Tony k]

Tony

My Lee .380acp sizer is .367” It works fine for me. I have not had any problems yet.

I do have one of their U dies for .32acp. I helped with sizing problems with different manufactures of brass.

Hmmm....that flies in the face of my hypothesis.

Maybe it's my choice of bullets. I was originally working with Berrys, which are .356. Neck tension seemed weak, but loads development was ok (not great). Sooty cases and inconsistent felt recoil.

I picked up some Xtreme rnfp, which are.355, and proceeded to work up new loads and found that I was getting inconsistent cycling, soot and unburned powder at moderate and even high published charges (power pistol and bullseye). Once I switched to the .223 die (about .002" smaller than the 380). It was like adding 10% more powder.

Maybe the .355" diameter bullets and the Lee die just created the perfect storm.

 

[Rule3]

My LEE .380 dies are also just fine and dandy. Why do folks always think it is LEE's issue?

All you need to do is send the die, some brass and some bullets to LEE and they will either fix or replace it.

No one on the internet can fix it for you.

 

[Tony k]

My LEE .380 dies are also just fine and dandy. Why do folks always think it is LEE's issue?

All you need to do is send the die, some brass and some bullets to LEE and they will either fix or replace it.

No one on the internet can fix it for you.

Go be rotten in someone else's thread.

You may not understand this, but sometimes when you encounter an issue it helps to talk it over with other people to come to a clearer understanding of the situation.

It's sort of the whole point of online discussion forums.

 

[Rule3]

Go be rotten in someone else's thread.

You may not understand this, but sometimes when you encounter an issue it helps to talk it over with other people to come to a clearer understanding of the situation.

It's sort of the whole point of online discussion forums.

Not being "rotten" But LEE is very helpful in resolve any issues with their dies. If you don't want to send it back to them as suggested, then don't.

You state "many people have issues with LEE 380 sizers", Is there data to support that?

Of course your measurements are within tight tolerances

 

[Tony k]

This is the first time I've ever had an issue associated with Lee dies. While I believe it's a problem with the die, I didn't want to go that route(send dies in) unless I was certain. Hence this discussion.
Here are some recent examples of people recommending undersize 380 dies to address similar issues.

Buy a Lee undersize die. http://leeprecision.com/undersize-sizing-die-380-auto.html

I had to get a Lee undersize 380 die because of neck tension issues.

 

[Rule3]

This is the first time I've ever had an issue associated with Lee dies. While I believe it's a problem with the die, I didn't want to go that route(send dies in) unless I was certain. Hence this discussion.
Here are some recent examples of people recommending undersize 380 dies to address similar issues.

I apologize if I cam across snarky. Was not my intent and actually trying to help you

There are several variables, the die, die set up,flare, taper, bullet, brass, gun and operator

How did you determine "improper neck tension".????
You stated, "I was getting inconsistent cycling, soot and unburned powder at moderate and even high published charges (power pistol and bullseye)".

That could be a number of things. Power Pistol and Bullseye are like night and day especially in a 380.

Anyway you state "While I believe it's a problem with the die, I didn't want to go that route(send dies in) unless I was certain"

Who ever answered your e mail at Lee was probably a CS rep and not a technician, For $5.00 or less and a week turnaround, you could send it to LEE with some brass and bullets and they will check and send it back.

Just my $.02.

 

[Tony k]

Operator error is the most likely cause when I'm the operator : ), but I'm reasonably sure it's not me with this.
Dies are set up based on Lee instructions for carbide sizer dies.

My first clue was that seating bullets felt much lighter than with 9mm and 45acp. I first attributed that to the thinner brass of the 380. However, I noticed that i could push the bullet deeper into the case with just my thumb and index finger.

At 243wxb's suggestion, I tried seating the bullet without expanding/belling the mouth. Was able to easily do so AND still possible to move the bullet with thumb and index finger.

When I switched to sizing with the 223rem die, I got great neck tension and perfect performance out of the 150 rounds I shot.

Yes, I was talking with "Laine" in customer service. Of course their solution was to sell me more stuff, lol!

You make a good point about sending it in , rule 3. I can get by with sizing on the 223 die until I hear back from Lee. It's cheaper than a new die.

 

[cfullgraf]

I did not see any discussion on the expander ball in the die that expands the case mouth and flares the case mouth. Maybe I missed it.

In any case, is the OP not getting enough neck tension before or after expanding the neck?

If he is not getting enough neck tension after expanding the neck maybe the expander is the problem. The expander plug can be chucked in a drill and the diameter reduced with Emory cloth.

If the bullet is seated in the case without expanding the neck and does not have enough neck tension, then the sizer die has a problem.

 

[Tony k]

I did not see any discussion on the expander ball in the die that expands the case mouth and flares the case mouth. Maybe I missed it.

In any case, is the OP not getting enough neck tension before or after expanding the neck?

If he is not getting enough neck tension after expanding the neck maybe the expander is the problem. The expander plug can be chucked in a drill and the diameter reduced with Emory cloth.

If the bullet is seated in the case without expanding the neck and does not have enough neck tension, then the sizer die has a problem.

Yep. I can seat bullets in sized cases without expanding.

 

[Walkalong]

I do have one of their U dies for .32acp. I helped with sizing problems with different manufactures of brass.

I cured my not enough neck tension problems in .32 ACP with an RCBS die set, replacing the Lee.

 

[Tony k]

I cured my not enough neck tension problems in .32 ACP with an RCBS die set, replacing the Lee.

I'm sort of leaning that way. It's why I was curious about inside diameter of other sizers.

But like you said earlier, rcbs is more expensive