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 Can 9mm and .357 Sig use the same bullets?
Messiah  [Team Member]
2/5/2009 11:26:57 PM
Are there any bullets out there can be used in either 9mm and .357 Sig? Yes, I am aware that .357 Sig is a PITA to reload for. Also, which die does everyone use for .357 Sig? I was on Dillons site and I don't know if I want to plunk down 150+ for a set of their dies.
Combat_Jack  [Team Member]
2/5/2009 11:46:41 PM
FMJs yes but in proper JHP loadings they use different bullets on account of the different velocities.
AeroE  [Moderator]
2/5/2009 11:52:14 PM
Both cartridges use a 0.355 inch diameter bullet.

AeroE  [Moderator]
2/5/2009 11:52:46 PM
Originally Posted By Combat_Jack:
FMJs yes but in proper JHP loadings they use different bullets on account of the different velocities.


Explain what you mean.
Combat_Jack  [Team Member]
2/5/2009 11:59:10 PM
9mm bullets are usually designed to run 200 fps slower than .357 Sig bullets. The latter uses a more heavily constructed bullet. Not in all loadings but in many of the better defense loadings.
NVGdude  [Member]
2/6/2009 1:22:55 AM
The bullets are the same with a few caveats.

For hollow points, the bullets designed for the .357 Sig are usually constructed heavier, either with a heavier jacket, or a shallower HP, because the expectation is that the bullet will be traveling faster.
For FMJ, some bullets designed specifically for the Sig have a flat meplat due to magazine length restrictions. Any truncated cone design should be fine though.

Most 9mm bullets will work just fine, you just need to be certain that you have good neck tension and are not over mag length.

As for dies, there is nothing wrong with Lee dies. Get the Lee die set, and also pick up a carbide .40 S&W sizing die. Run the brass through the .40 die first, then the .357 Sig die, and you should not have to use any lube.
ViniVidivici  [Team Member]
2/6/2009 2:27:59 AM
Originally Posted By AeroE:
Both cartridges use a 0.355 inch diameter bullet.



This.
skylark  [Member]
2/6/2009 5:21:30 AM
I've been loading 124 grain Flat Point Berry's plated bullets in both 9mm (1100 FPS) and 357 Sig (1250 FPS) for years with great accuracy results. Just make sure you buy bullets with the shortest profile for 357 Sig. Long pointy bullets don't work. If you are not sure, take a look at some 40 cal bullets and compare their profiles. 40 S&W and 357 Sig have the same magazine length loading constraints thus generally have the same bullet profiles.
Messiah  [Team Member]
2/6/2009 10:02:51 AM
Thanks guys! So any of the flat point 9mm/.355 bullets should work just fine for both calibers?
FunBobby  [Team Member]
2/6/2009 1:25:13 PM
Originally Posted By skylark:
I've been loading 124 grain Flat Point Berry's plated bullets in both 9mm (1100 FPS) and 357 Sig (1250 FPS) for years with great accuracy results. Just make sure you buy bullets with the shortest profile for 357 Sig. Long pointy bullets don't work. If you are not sure, take a look at some 40 cal bullets and compare their profiles. 40 S&W and 357 Sig have the same magazine length loading constraints thus generally have the same bullet profiles.


A +1 here for using 124gr flat point Berry's in .357SIG