.380 Cases Bulging

[Donny1]

This is my first experience with loading .380. I didn't have a problem with my first 50 that were from a box I purchased new and reloaded but today using some mixed once fired cases I bought from a CG member I'm having an issue with a slight bulge on some of them and some got crushed when trying to seat the bullet. Headstamp didn't matter.

I opened up expander die, didn't help, then backed off the seating/crimp die to where it's barely touching the rim. It's no longer crushing any cases but some still have a slight bulge. I occasionally get this with 9/45 with mixed brass but it seems these .380 cases are a bit fragile. Should I back off the sizing die? Will that not pinch the top as much?

Lee Carbide 3 die set and Berry's 100gn CPRN.

The spec says .356 for .380 and these are .355 so they should seat smoothly. It's just a bit frustrating to ruin primed cases when supplies are limited

[divingin]

Which step (if any) causes the bulge?

Several possible causes:

1) Bulge is on the fired, but otherwise unprocessed brass. Sizing may take care of it, but if it's the bases that are causing a problem, you may need a push-through die. Easiest solution: source other cases.

2) Bulge shows up on sizing (unlikely): too tight a sizing die?

3) Bulge shows up on expand/flare: Trying to flare an excessive amount, or the expander portion of the plug is too large. Brass may be heavier in the web, which will cause this as well.

4) Bulge shows up on seating (w/no crimp being applied): Bullet too large in diameter or too long; alternatively the same thick brass mentioned in the previous step. Insufficient flare can place undue force on the case mouth while seating, causing the bulge further down the case. Bullets seating other than straight can cause a bulge on one side where the bases expand the brass outward.

5) Bulge shows up while crimping: Trying to apply too much of a crimp can cause the mouth to set back, forming a bulge further down the case.

Break your process down into individual steps and you should be able to ID what's actually causing the problem.

[bohoki]

berrys copper clad are different than fmj but if its just expanding around the bullet it may jsut be a case of "mae-westing" its what happens with carbide sizing dies (really noticable on 30 carbine)

[Donny1]

Which step (if any) causes the bulge?

Several possible causes:

1) Bulge is on the fired, but otherwise unprocessed brass. Sizing may take care of it, but if it's the bases that are causing a problem, you may need a push-through die. Easiest solution: source other cases.

2) Bulge shows up on sizing (unlikely): too tight a sizing die?

3) Bulge shows up on expand/flare: Trying to flare an excessive amount, or the expander portion of the plug is too large. Brass may be heavier in the web, which will cause this as well.

4) Bulge shows up on seating (w/no crimp being applied): Bullet too large in diameter or too long; alternatively the same thick brass mentioned in the previous step. Insufficient flare can place undue force on the case mouth while seating, causing the bulge further down the case. Bullets seating other than straight can cause a bulge on one side where the bases expand the brass outward.

5) Bulge shows up while crimping: Trying to apply too much of a crimp can cause the mouth to set back, forming a bulge further down the case.

Break your process down into individual steps and you should be able to ID what's actually causing the problem.

I have no issues until the seat/crimp die.

I backed off the sizing die and it's not touching the shell holder but the cases still chamber fully with no resistance. I think it is a combination of things, different brass, not enough bell, to much crimp in the seating die, ie, starting the crimp before it's fully seated.

I just loaded 20 and had a minor bulge on a couple but none are getting crushed anymore. I read on some other threads about separating headstamps and not using the seating die for any crimp, then using the Lee FCD after. Ironically this is the first Lee set I opted to not get the 4 dies (FCD) because I've found it unnecessary for 9 and 45.

[ojisan]

Crimping as a separate step is the way to go.
Life is better when we do this.

[hermosabeach]

+1 2 stages

Crimping as a separate step is the way to go.
Life is better when we do this.

Some will seat the bullet with 2 passes.. a short press and then check that it is straight and then finish the seat / crimp movement.

Others will seat all projectiles... re adjust the crimp and run though a crimp only stage...


If you take a factory new round and run it through your set up, what happens?

Does it set the bullet further into the case? is it hard- meaning you are adding crimp?

What is the COAL vs the book max min?

[Donny1]

Some will seat the bullet with 2 passes.. a short press and then check that it is straight and then finish the seat / crimp movement.

Others will seat all projectiles... re adjust the crimp and run though a crimp only stage...


If you take a factory new round and run it through your set up, what happens?

Does it set the bullet further into the case? is it hard- meaning you are adding crimp?

What is the COAL vs the book max min?

I just loaded another 50 and it's going fine but maybe I will order the FCD for this set. The only factory ammo I have is SD HP.

As far as the COAL my setup is:

CFE Pistol 3.5gn
Berry's 100gn CPRN
.980

I think the max is .984 for .380

FYI and not really relevant, I loaded these at 3.3gns and they chrono at 650fps but they shot almost like a .22lr. I'm trying to get the wife back out to shoot and she is recoil sensitive with some pistols so I think she will have no issue with these. I only bumped it a little because even though they cycled fine they were falling right next to me so they need a little more pop. After this batch I'm going to load the freekshow recipe with 231.

[five.five-six]

This is my first experience with loading .380. I didn't have a problem with my first 50 that were from a box I purchased new and reloaded but today using some mixed once fired cases I bought from a CG member I'm having an issue with a slight bulge on some of them and some got crushed when trying to seat the bullet. Headstamp didn't matter.

I opened up expander die, didn't help, then backed off the seating/crimp die to where it's barely touching the rim. It's no longer crushing any cases but some still have a slight bulge. I occasionally get this with 9/45 with mixed brass but it seems these .380 cases are a bit fragile. Should I back off the sizing die? Will that not pinch the top as much?

Lee Carbide 3 die set and Berry's 100gn CPRN.

The spec says .356 for .380 and these are .355 so they should seat smoothly. It's just a bit frustrating to ruin primed cases when supplies are limited

[hambam105]

Definitely two step seat & crimp. Lee FCD is a plus.


For those who do not know of...or believe that the terms 'Expansion' and 'Flaring'
are synonymous reloading terms should take note.

https://youtu.be/pcc91NArteQ

[robert101]

Make sure you are seating straightly. .380 is a little finicky sometimes.