.357 Magnum case length

[blackthunder]

I bought 300 cases from the local gunshop of used 357 mag brass, cleaned and resized them with my Lee die.. loaded 10 up and saw I was getting very inconsistant crimps which were caused by the different lengths of brass. (I am using the Lee Factory Crimp Die)

I thought my solution was to buy a lee case trimmer for the .357 mag, but it doesn't touch most of the brass. The Lee trimmer trims it to about 1.280. 80% of my brass seem to be in the 1.280 - 1.270 range.

Would it be safe to trim all of them down to 1.270 to catch 80%+ of them? The Lee manual states the max length is 1.290.

Should I be concerned with the shorter case and smaller volume?

I am using Lee 158gr SWC TL bullet, do people have good luck getting a sufficient crimp to handle being loaded in a lever actions tubular mag?

thanks,

[Flinchrock]

I have done exactly that in the past, and used the cases for lower powered practice loads.

[Motor]

I think your trimming plan is just fine. If you care to look it up there is a SAMMI spec for the case length. It may be even shorter than 1.270" Doesn't Hornady trim them down even more for the Leverevolution bullet?


One thing caught my eye in your post. The Lee FCD. Be very carefull using that die with cast or swaged bullets. If the carbide ring, that is supposed to "iron out" bulges, is smaller in diameter than your boolit + the case wall thickness x2, you could size your boolit down right inside the case. This is a VERY BAD THING because the brass springs back and the boolit does not so you lose most if not all of your neck tension. No amount of crimp can make up for no neck tension.

[Airman Basic]

I trim all my newly acquired pistol brass to my standard length, before initial sizing, to solve the consistent crimp problem. Check the lengths with a case gauge before chucking in the trimmer. Then you're left with just the overlength few to deal with.

[trapper9260]

Also if you have any short case you can use them for 38spl. that way you will have more life for the case because in a 357 you can also shoot 38spl also.

[shooting on a shoestring]

.357 and .38 cases are long. Trimming them short by .010 or .020" is a tiny percent change in case capacity. Not noticable to me in terms of powder charge/pressure. I trim mine to the shortest length in a "lot" and don't change my load. I do reset my seat/crimp die for each "lot" of brass I load to get pretty crimps (and I use light crimps).

[dragon813gt]

One thing caught my eye in your post. The Lee FCD. Be very carefull using that die with cast or swaged bullets. If the carbide ring, that is supposed to "iron out" bulges, is smaller in diameter than your boolit + the case wall thickness x2, you could size your boolit down right inside the case. This is a VERY BAD THING because the brass springs back and the boolit does not so you lose most if not all of your neck tension. No amount of crimp can make up for no neck tension.
The OP did not specify which style FCD he was using. Lee makes a rifle style, collet, FCD for 357 Magnum as well as a few other cartridges. So your concerns could not matter at all. Just wanted to point this out since the OP did not state which style he was using.

[wallenba]

Most of my .357 brass has always been a little short. I just trim them all even, taking off as little as possible to do it. Never been a problem. Loading max loads with cannelure J's might seat them deeper than desired to achieve proper crimp. But we're usually talking of just a few thousandths here.

[Motor]

The OP did not specify which style FCD he was using. Lee makes a rifle style, collet, FCD for 357 Magnum as well as a few other cartridges. So your concerns could not matter at all. Just wanted to point this out since the OP did not state which style he was using.

Thanks for this info. I did not know they made the "rifle style" FCD for calibers that are traditionally pistol calibers.

Lee should have gave them different names. Calling them both (rifle and pistol) FCDs has caused sooo much confusion.


Motor