Some help/advice needed – Lee 358-105 SWC and 380 ACP

[bedbugbilly]

I have two .380s - S & W 380 EZ and a nice sock drawer Beretta 84 .380. I have had the Beretta for a couple of years and I have the itch to shoot it and the 380 EZ more – primarily for plinking and killing cans.

In the past, I have loaded 95 grain .356 Round Nose – PC’s that I bought from a vendor on this site. For the cartridges I loaded, they seemed to shoot well in the EZ. My data sheet shows that I was using 2.5 grains of Bulls Eye under the 95 grain – COAL of .975”. They seemed to feed and function just fine in my EZ.

So today, I finally had some time to sit at the bench and play a little. I hae read several threads here where some really like using the Lee .358-105 SWC boolit in their .380s. I have used this boolit quite a bit in loading plinking rounds in 38 Colt Short and it shot very well. I have a jar already cast up of them so figured I would make some dummy rounds and try to see how they cycled in the .380 Smith EZ.

I am using “range brass” – a quick measurement of a half a dozen from my bin shows them to be .668” + or - in length. My 3rd edition of the Lyman Cast Boolit Handbook shows a trim length of .677. They are mostly 1X fired range brass and they are what they are for mixed headstamp brass.

I took some of the Lee 358 – 105 SWC and ran some through my Lee .356 push through sizing die and then ran some through my Lee push through .357 sizing die. My .356 die sizes at .3565 and the .357 seems to be right on atm .357. I use “range lead” and the mold drops them at right around .358.

In making dummy rounds, I used both the .3565 and the .357 sized to try and see which worked best. Both seemed to chamber just fine so I'm guessing I would probably go with the .357 if they will work in the Beretta when I try dummy rounds in that handgun.

MY PROBLEM . . . or lack of knowledge . . . is in reading the posts on here in regards to the 358-105 SWC Lee boolit in .380 ACP, I have never seen any information on how deep they are seated and what the finished cartridge overall length is?

I seated some to the center of the middle band and taper crimped – tried then in my .380 cartridge gauge and they fit fine, but when I loaded them up in my magazine of the EZ and tried cycling them, they did not feed well – the nose hit the beginning of the chamber opening (i.e. seemed to feed too high), which to me, would indicate that they needed to be seated deeper. So my next experiment was to seat them so that the top of the casing was just a tad below the edge of the top band towards the boolit nose. These were taper crimped, tried in the gauge and they seem to chambder and hand cycle O.K.

So, what I ended up with was a COAL of .890. This iis shorter than my COAL using the 95 grain RN boolit which has a COAL of .975”.

I measured my boolit length and it showed a measurement of .5125 (358-105 SWC).
My COAL was .890” My case length is .668” so that means the 358-105 SWC is seated into the cartridge case a depth of .290”.

Can those that use the Lee 358-105 SWC in .380 acp possibley post what your cartridge overall length is? Am I correct that this boolit needs to be seated to the middle of the top band and crimnped – or are you doing it otherwise?

I don’t want to “overthink” this – I just don’t want to seat too deep and end up with a pressure issue.

Any suggestions for loading data for this boolit with either Bulls Eye or Red Dot? Those are the two powders I am limited to at this time.

I saw one post where a member was using 2.4 grains of RD with this bullet out of his Bersa and was having good luck with it – but again, no seating depth or COAL was given. I have done some searches but haven’t come up with much in regards to this particular boolit and how it is being loaded in 380 acp. The Lee manual was no help at all.

My goal is not to load hot – but rather to have a decent plinking round that could work in both the EZ and the Beretta 84. There is quite a difference between the recoil spring strength of the EZ and the Beretta,, which is much stronger – so perhaps a round for the Beretta may need to be a few more tenths of a grain to cycle it as opposed to the EZ? I’m more of a revolver guy, but I ran into having to switch from 3.5 grains of BE with a 122 grain RN in 9mm for the Ruger SR9 and my 9mm Shield. The Shield required a 3.7 grain load to cycle well – so I know that happens occasionally.

Any advice / info would be greatly appreciated. I realize all .380s are different. I’m just not sure of how deep to seat the 105 grain SWC nor what charge of BE or RD would be considered “mid-range” as far as miniun/maximum with the 105 grain SWC.

Thanks.

[whisler]

I used .969 +/- .002 with mixed brass and they feed in several different .380s. Can't say what original case length was though. I used 231 so no help with load. I think the usual suggestion is just a finger nail thickness of top band showing above case mouth. Worked for me.

[bedbugbilly]

Hmmmmm . . . . I went back out to the bench and rechecked my measurements. I seated so that the edge of the case mouth was on the top band and a fingernail thickness of the top of the top band (babd closed to the nose) is showing - that gives me a cartridge overall length of .890".

If I seat the top of the case mouth to the bottom edge of the same top band, it gives me a cartridge overall length of .950" - but when a taper crimp is applied, the case mouth has nothing to crimp against except the top groove and I have always crimped against a band (taper crimp).

Seating the top of the case mouth against the center band with a finger nail thickness of the top of the middle band and taper crimped - it passes the 380 gauge but does not feed/hand cycle without the dummy round jamming - it won't feed into the chamber from the magazine.

whisler - if your are seating and crimping on the top band with a fingernail thickness of the top of the top band showing and you have a COAL of .969" - you have me scratching my head as to why, if I am seating the same way, my cartridge overall length with the 105 grain is .079" shorter? Even with my range brass being .009' less than the Lyman CBHB recommendations - and I have to believe that most range brass used by folks can be a tad short _- I can't see why my COAL is off so much? Thus my concern about case volume and possible pressure issues.

[sixgunner452]

I shoot Lee 105 in mixed 380 brass too. 2.3 to 2.5 Reddot. Buller seated as stated above. Sliver of top band exposed. Cheap, soft shooting load. Randy

[Thin Man]

+1 for seating the Lee 358-105 SWC boolit to leave a short length of the front band outside the case mouth. I have been using this boolit and method for many years and have not yet found a pistol that would refuse to feed and function with this formula. Just out of lazy boredom I size the castings at .358 for revolvers and use them as sized for the .380 loads. Why they work is anyone's guess, but work they do. I use multiple different powders and charge weight is the starting charge for a 95 grain boolit as published by known sources.

[bedbugbilly]

Thank you all for the info - greatly appreciated.

Thin Man - I did a bunch of searches last night on the general internet and ran across several threads on other sites where the 358-105 SWC Lee was mentioned, but more or less that they "used it" in their 380s with good results - but very little information about seating depth, COAL, etc. My 4th edition Lyman Cast Bullet Handbook is out at our place in Arizona and I can't remember if there was anything in the 380 acp section that showed info on this particular boolit. One of the posts I read - and I believe the fellow was talking about his Walther PPK IIRC, he said that he had been sizing the boolit down from .358 for his .380 and he was getting "acceptable" results - something like 4" groups at 7 yards or so. He tried the boolit at .358 and was not only surprised that it chambered but also how it was more accurate and his groups tightened up - so you may be on to something there by loading them up at .358.

My 2 cavity mold - probably 20 years old? - drops at right around .358 or a tad bigger. Certainly worth a try to run them through the .358 sizer and load up some dummy rounds to see how they chamber.

[whisler]

Your post got me curious so I got out the load book, calipers and the loads that I had. It appears that I was "less correct than usual". The load length is indeed 0.969 as recorded but the round is crimped into the band just above the bottom of the band. The band measures .075 on my example and I guesstimate that the crimp is about .015 or so above the bottom edge. They work as loaded in my 2 .380s.

[bedbugbilly]

Thanks whisper - that makes dense when I look t mine. I'll take your measurements and make a couple of dummy rounds and see if they handle in my pistols. Thanks for checking - maybe that will help on my hangups when hand cycling.