.358 Winchester Bullet Seating Problem

Slooshark1

Slooshark1

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Okay, so here's the problem. Earlier this week I dug through my empty cases box and picked out a bunch of .308 Brass. I resized these to .358 Win and trimmed them and then I annealed the necks on them and dried them out over a few days. Well yesterday I went to start seating bullets and was having problems with the shoulders buckling on them. I kept trying and some would seat but probably over half of them crumpled. I came to the conclusion that perhaps I had overheated the shoulders when annealing them. So I went to my local reloading store and bought a bag of brand new .358 Win brass. I primed them and went to start seating bullets and the first three crumpled like a cheap lawn chair. I ran a .358 neck expanding die through one and tried again and it still crumpled. I don't have the die screwed in too far, I checked that. I'm not seating the bullets too deep, just to the cannelure. The bullets are .358 200 Gr Hornady Round Nose.

What am I doing wrong?


 
Did you bevel the edges enough if your using flat base bullets. Also try to screw the seating die in a bit more maybe to support the neck more. I had the same problem till I beveled the edges better. Also are you using graphite for a lube in the case mouth.
 
I'm not using graphite but I'll try bevelling the edges of the case mouth and see if that helps.

Thanks,

Slooshark1
 
Slooshark A couple other things that may help. Have you measured the diameter of the expander on your dies? If you had an expander from a 338 cal rather than 358 your necks could be undersized and you would collapse the necks. Also regarding your case annealing. If you over heated the cases before you dumped them in the water the necks will be dead soft. Suggest you anneal them before you resize them. This will start the work hardening and may help. I suspect chamfering the case mouths will solve most of your problems
 
It worked! I bevelled the case mouths and the bullets went in smooth as cream. Thanks for your help. Too bad I buggered so many cases before asking, though. Live and learn.

Thanks again,

Slooshark1
 
When seating flat base bullets with a sharp edge at the base (many 30-30 bullets) I use the Lee universal case mouth expanding die. It adds a touch of flare which is removed with the crimp. I prefer this to bevelling the case mouths.
 
Slooshark1 said:
It worked! I bevelled the case mouths and the bullets went in smooth as cream. Thanks for your help. Too bad I buggered so many cases before asking, though. Live and learn.

Thanks again,

Slooshark1
Click to expand...

The good part is, since you now know what the problem was, you can make as many 358 cases as you want using readily available 308 brass! I have formed many hundreds over the years, most from brass picked up at the range, and they work fine.

Ted
 
Another approach is to simply skip the case mouth bevelling and pick up the proper size M die. As the 358 Winnie is a natural for cast bullets, the M die is pretty handy anyways.
 
take a bullet and color it with a sharpie make sure you get the base of the bullet as well.
with the ram in the upstroke position screw the seating die until it touches the shell holder and than unscrew 2 full turns, tighten the lock ring at that position, so there is a visible gap between the ram and die.

try seating a bullet very slowly until you feel it hit something, back off . take bullet out and look to see if there is a ring mark at the base of the bullet, that will let you know if you need to flare and also how much flare is needed.
hope this info helps.
 
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