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BCB
03-26-2015, 03:46 PM
I am going to size a few round nose 357 Magnum boolits that I have down to possibly use in a 9mm...

The boolits are presently 0.358"...

Is there a preferred diameter for the 9mm when it comes to cast?...

I know, could be both of the diameters mentioned, but which might I have better luck with--playing the odds a bit rather than purchase both sizes...

Thanks...BCB

clintsfolly
03-26-2015, 03:52 PM
I shoot my 9 mm at .358. Load a few dummies and see if they feed and seat. Clint

BCB
03-26-2015, 04:00 PM
I shoot my 9 mm at .358. Load a few dummies and see if they feed and seat. Clint

Indeed...

I had heard that some use 0.358" as you confurmed...

Maybe I will load a couple that size just to see...

Thanks...BCB

Outpost75
03-26-2015, 04:01 PM
In 9mm best results will be had with the largest bullet diameter which chambers easily and extracts loaded rounds without effort.

Brass thickness varies all over the map and so do 9mm chambers.

Most NATO STANAG 4090 chambers will shoot best with .358 bullets and will accept these when loaded in common US commercial brass. Military brass which is heavier walled causes problems, where the interior case wall begins to thicken b elow the bullet base. If you load a bullet having a seating depth greater than military hardball, the bullet base impinges against the internal case wall taper where it begins to thicken, causing a bulge about midway down the case body.

US SAAMI dimensioned chambers usually accept bullets of proper profile when of .357 diameter. European barrels with CIP or NATO chambers usually will accept .358.

The key is to cast your chamber. Measure the mouth diameter of the chamber prior to the stop surface where the case mouth headspaces and ALSO the "ball seat" diameter, which is the unrifled portion in front of the headspacing stop surface before the rifling starts.

ALSO measure the diameter of dummy cartridges assembled with your chosen bullet. After you have determined that the dummies chamber and extract easily, without resistance, MEASURE the rounds which "work." It is absolutely necessary that the loaded cartridge diameter be 0.0015" less than the chamber to allow for safe bullet release, and in semi-auto pistols a somewhat greater clearance of 0.002 or so is generally necessary to ensure smooth feeding.

A bullet design which works well in 9mm autopistols and carbines, is the Accurate 35-155D. While the drawing specifies .36 driving bands, you can "tweak" diameters on a mold when you order and specify alloy. Note also its short base to crimp groove distance, which is the same as 123-grain FMJ ammo. Note "nose tolerance negative" which ensures a good throat fit, without the bullet forepart impinging against the origin of rifling.

In the SIG P210 match pistol a charge of 3.0 to 3.2 grains of Bullseye is highly accurate, producing ten-shot groups of 10cm or less at 50 metres, approximating .38 Special +P velocities.

135115

tazman
03-26-2015, 04:21 PM
Definitely load some and see if they will chamber in your pistol.
I can load boolits as large as .360 in my 9mm but it is more accurate with .358.

captaint
03-27-2015, 09:37 AM
I HAD to go to .358 to stop the leading in my 9mm. It worked, so now that's all I do for the 9.

BrassFerret
03-27-2015, 01:24 PM
That's really interesting! I have three '9mm's.

I have a Glock G19 (still trying to decide if I am going to use cast boolits in this one...everyone here in SA says no to that). I have a Taurus PT1911 in 9mm, which has been with a pistolsmith getting some renovations done for IPSC and Steel. It has a .356" bore (Groove Dia). and my Ruger Blackhawk 9mm/.357 Magnum Convertible. It seems to shoot .355" Frontier 124 grain CMJ's really well. Its bore slugs out at .3575".

I decided to size my boolits for the Taurus at .357" after discussing it with Tom. I know a guy here with a SIG-SAUER that slugs out at .3585".

There is a Sticky on this Forum by 44mtgun that explains sizing boolits for the 9mm...very informative I must say!

fredj338
03-27-2015, 01:43 PM
Most of the guys I know are sizing 0.357" for their modern guns. Some of the older bores can be larger. Try some @ both, check for function, leading & accuracy.

fredj338
03-27-2015, 01:45 PM
That's really interesting! I have three '9mm's.

I have a Glock G19 (still trying to decide if I am going to use cast boolits in this one...everyone here in SA says no to that). I have a Taurus PT1911 in 9mm, which has been with a pistolsmith getting some renovations done for IPSC and Steel. It has a .356" bore (Groove Dia). and my Ruger Blackhawk 9mm/.357 Magnum Convertible. It seems to shoot .355" Frontier 124 grain CMJ's really well. Its bore slugs out at .3575".

I decided to size my boolits for the Taurus at .357" after discussing it with Tom. I know a guy here with a SIG-SAUER that slugs out at .3585".

There is a Sticky on this Forum by 44mtgun that explains sizing boolits for the 9mm...very informative I must say!

I shot 1000s of lead bullets in my 1st Gen G17 with no issue. Just clean it more often.

rototerrier
03-27-2015, 02:24 PM
I get good accuracy with .356 Powder Coated. I lubesize to .357 when using Carnauba Red.

DougGuy
03-27-2015, 02:55 PM
Hi fellas, after numerous requests, I am adding 9mm, 10mm/.40S&W throating reamers to the tooling, should be here tomorrow. I will be able to throat 9mm barrels to both .3575"+/- .0002" and also .3585"+/- .0002"

BCB this will allow you to load whatever diameter you choose, and seat to whatever COA you choose, as the boolit will easily pass the "plunk" test after throating and polishing the barrel.

gwpercle
03-27-2015, 07:24 PM
My Walther P38, my son's Beretta and two friends who have Springfield-Armory 9 mm's, all do fine with my cast boolits sized .357.
I selected this size because I had a .357 sizing die, it works just fine.
Gary

h8dirt
03-28-2015, 08:46 AM
In my experience, 358 for Beretta and 357 for Sig. FYIW.

trapper9260
03-28-2015, 08:50 AM
In my S&W it is 356 and in my tarus is 355,the tarus is a wheel gun with moon clip.The bigger will not chamber in the cylinder.

tomme boy
03-28-2015, 09:26 AM
I size to 0.3586" as this is what my 0.358" die sizes at. It works in 6 different 9mm pistols I have tried them in. Not a single one has leaded since I went to this die. The 0.357'' die would lead just a little bit.

ioon44
03-28-2015, 09:51 AM
I am using .357" with Hi-Tek coating in my Glock G 19 factory barrel, no leading and accurate.

Shiloh
03-28-2015, 03:01 PM
What boolit??

SWC don't feed well. Have to smack the back of the slide to seat.

Shiloh

BCB
03-28-2015, 03:29 PM
What boolit??

SWC don't feed well. Have to smack the back of the slide to seat.

Shiloh

Guess I just assumed all would know I was going to use a round nose boolit...

Isn't that pretty much what the 9mm uses?...

Thanks...BCB

DougGuy
03-28-2015, 03:32 PM
What boolit??

SWC don't feed well. Have to smack the back of the slide to seat.

Shiloh

Sounds like your barrel needs a slighly larger diameter throat! What do you think will happen if you smack the slide to force it into battery, and instead of the boolit seating in the throat, it sets it back into the case? Easy way to cause a KABOOM!


Hi fellas, after numerous requests, I am adding 9mm, 10mm/.40S&W throating reamers to the tooling, should be here tomorrow. I will be able to throat 9mm barrels to both .3575"+/- .0002" and also .3585"+/- .0002"

BCB this will allow you to load whatever diameter you choose, and seat to whatever COA you choose, as the boolit will easily pass the "plunk" test after throating and polishing the barrel.

Reamers are here in house, in hand, they look really good with a long 3° taper into the rifling. Let me know if you need throat work done..

MtGun44
03-28-2015, 06:17 PM
Lee 356 120 TC at .357 or now .358 has proved to be a very reliable
feeder and works in all my 9mms. RN are often problematic unless
they have a slight shoulder, since the full diam portion of a RN often
fouls the short throated guns.

Strongly recommend this mold for the shortest route to no problems
with 9mm.

The original 9mm factory ammo was truncated cone.

ProfGAB101
03-28-2015, 07:10 PM
I recently slugged my 4 groove Makarov 380 and it was like .3574 so I will be looking to add a sizer in the .3576-.3580 range.