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Will
06-06-2012, 09:16 AM
Loading some 9MM 356402 and have been seating them so the top band is almost completly covered, flush with the case mouth. I felt that the sharp edge of the top band might catch on the chamber and cause and cause a hangup. Do any of you load this boolit with the top band exposed and are there any problems with it? Would it be better to just cover the lube grove?

Will

sig2009
06-06-2012, 12:01 PM
The Lyman reloading manual has the 356402 cast bullet oal at 1.110

gray wolf
06-06-2012, 12:30 PM
I would think the pistol should tell you how long they should be.
Don't Know if I would just pick a number cause i thought it might hang up.
Have you tried to cycle a magazine full ?
Have you tried using your barrel as a gauge ?
Sounds like your past the crimp groove ?

gray wolf
06-06-2012, 12:31 PM
I would think the pistol should tell you how long they should be.
Don't Know if I would just pick a number cause i thought it might hang up.
Have you tried to cycle a magazine full ?
Have you tried using your barrel as a gauge ?
Sounds like your past the crimp groove ?

40Super
06-06-2012, 01:15 PM
I'm guessing that is a swc design? I usually seat them with .02 to .06 of the shoulder sticking above the case mouth, depending if they feed good. Try loading them longer and test in your barrel, if they don't go seat another .01 deeper and repeat till they chamber. Then load up a couple and cycle them in the gun to see how they feed .

MtGun44
06-06-2012, 01:43 PM
402 is a truncated cone.

The magazine limits the maximum LOA, and the chamber also will limit what will
chamber - how much of the full diameter part can be out of the case without binding
in the throat against the rifling.

Also, the 9mm has a very small case volume. As you move the base of the boolit deeper
than the loading data that you are using did, you are increasing the pressure due to
decreasing combustion chamber volume. If the base is significantly deeper, reduce the
powder charge proportionally and work back up.

You need to use the dismounted barrel to tell you how far out you can seat the boolit,
the loaded round needs to drop into the chamber freely so the base is flush with the
breech face location or at most a 1 lb fingertip force to seat the round. Look for marks
on the full diameter portion of the boolit out of the case to see if it is hitting the rifling.

Check out the sticky on "Setting up a new 9mm for boolits", it might save you some time.

Bill

40Super
06-06-2012, 06:18 PM
Now that I'm home and see what bullet your working with I see that is one of mine. I seat them to an oal of 1.135, they fit in my Berettas and XDm and Storm Lake barrels.

Jagdhund
07-09-2012, 05:29 PM
Years ago (in fact, the first pistol cartridges I ever loaded), I used the 356402 in a Wehrmacht issued Browning High Power. I don't know what the OAL was, but I believe a great deal of the shoulder was seated out. I just loaded 356402 for a newly acquired Stoegar Cougar 8000 last weekend. Used Lyman's minimum 1.110" OAL. No feeding problems in the turn-barrel system. Yesterday, I figured out I can seat 356402 out to about 1.125" in the Cougar. That length fits the mag with room to spare. I'm going to test the new OAL to see if it helps the Cougar's accuracy (not really bad, but just mediocre at this point). I also tested a custom cast bullet that looks like the Lee TC bullet w/lube groove (or a SAECO 377 design?). It also fed without a hitch. I'll be able to see which the Cougar likes best.