9mm vs 357sig bullets?

[Yamaha]

I'm going to be getting into loading within the next week, I just had one question.

9mm is .355 measurement, .357 sig is .355 measurement(i think), as long as I used similar grain weights, would I be able to use basic 9mm bullet components?

this help would be appriciated

 

[boman]

Both cartridges use .355 bullets---small pistol primer---check powder manufacturers for recommended powders but should be the same---

Steve

 

[XtremeVel]

I'm going to be getting into loading within the next week, I just had one question.

9mm is .355 measurement, .357 sig is .355 measurement(i think), as long as I used similar grain weights, would I be able to use basic 9mm bullet components?

this help would be appriciated

You are correct, .357 sig is also .355.

As for using the same bullet though... There are a couple of things to remember if interchanging the bullet between the (2) calibers...

First, think about the construction of the bullet... You won't want to use a CAST or PLATED bullet regardless of weight and drive it to .357 velocities... The bullet I like are the bulk Hornady 124 gr FMJ-FP. These are JACKETED and can be driven to the higher velocites...

Second thing to watch is the shape of the bullet. The .357 has a very short neck and your bullet will need to match up so the bearing surface of the bullet that contacts the neck is straight when seated to the proper OAL.... You can not fudge the OAL too much to match this up due to creating high pressures if seated too deep and feeding issues if seated too long...

Like said above, the Hornady 124 FMJ-Fp works great and is a relatively cheap bullet for target shooting full power loads... A few others that I found will seat correctly and match the short neck are the Hornady 124 & 147 gr XTP's, Speers 125 & 147gr Gold Dots, and Sierra 115 gr JHP... I am sure there are many more, but these I have actually tried and they would be fine !

Lastly, there would be no reason you couldn't use a FP style PLATED bullet as long as you downloaded to probably 9mm cast load level... But, I don't do that because I would just assume to shoot 9mm then...

 

[Yamaha]

my first project after i get the setup will try to make a "critical defense" round for the 357 sig since hornady wont make them for me.....lol

 

[XtremeVel]

my first project after i get the setup will try to make a "critical defense" round for the 357 sig since hornady wont make them for me.....lol

They offer that bullet for reloaders ? Guess I never paid much attention since I have already have my favorite... If they don't or you cant find them, the 125 gr Gold Dot would serve you well allso. It is actually constructed for that kind of velocity...

You will have fun loading that cartridge... Actually, I load 8 different handgun carridges, and I can honestly say that round is the only one that the hotter I go, the tighter my groups become ! Usually I find in other calibers the most accurate load is usually closer to the starting load than the max....

If you are new to reloading, be careful with any caliber, especially with this round. That short neck MUST hold that bullet secure... Preventing bullet set-back is very important... The neck tension on the bullet is very important, along with a proper taper crimp....

 

[Aszerigan]

I would recommend using FMJ bullets, not plated. Standard velocity for a .357 SIG w/125gn bullet = @1300+ fps. This is 100fps faster than you should push a plated bullet. Will it work? Sure... I've loaded many like this. But for self defense rounds, buy JHP's.

Also.... if you're going to use Berry's bullets to save a few dollars, don't buy the 125gn JHP's for your 357 Sig. The oglive is too great and the shoulder on the bullet is too high. They will not feed.

I'll agree with XtremeVel on this - don't just jump into loading this caliber. Its a HUGE pain, and very dangerous if you don't get the neck tension correct. I don't really load it anymore for this reason.

 

[Yamaha]

They offer that bullet for reloaders ? Guess I never paid much attention since I have already have my favorite... If they don't or you cant find them, the 125 gr Gold Dot would serve you well allso. It is actually constructed for that kind of velocity...

You will have fun loading that cartridge... Actually, I load 8 different handgun carridges, and I can honestly say that round is the only one that the hotter I go, the tighter my groups become ! Usually I find in other calibers the most accurate load is usually closer to the starting load than the max....

If you are new to reloading, be careful with any caliber, especially with this round. That short neck MUST hold that bullet secure... Preventing bullet set-back is very important... The neck tension on the bullet is very important, along with a proper taper crimp....

I think ill buy a box of 9mm hornady critical defense to break down components and measure the bullets, and no, as far as I know that's the only way to do it....lol I don't think its available to buy separately. Thank you guys for the replies, ill rep everyone when im on the compy, phone wont let me