Can a 358 cast boolit be sized down to a 355?

[Darklin]

With the current stat of things in the country and not being able to find a .355 boolit mold does anyone know or has anyone sized a .358 down to .355 to shoot in the 9mm? I have a .358 mold @ 124 Grains. Will this work or do I need to keep looking for a .355 mold??

[GARD72977]

.003 is not ideal but works fine.

What do you need .355 for?

[ButchC]

If you can get away with .356 it makes your life easier if you have the option to size up a bit. If your mold drops .358 with a #2 or other harder alloy, wheel weights or wheel weights cut with some pure lead might drop the cast size down to .357 and make for an easier time of things. Depending on your velocity, you might be able to get things figured out quite well with what you have on hand. Going down more than .004 and things become challenging, how much so can depend on your sizing setup.

[1eyedjack]

Yep! Size a MP359 125 hollow point cast of WW with a bit of pewter powder coated to .356 for my 9mm....harder alloy might be more challenging proposition....I've been using Lee push through sizer dies with an APP press with no problem.

[fcvan]

I have shot at .358 for 36 years, and it works in every 9mm I own or have owned. As cast, .358 even though it is a .356 mold. I ran them through a Lyman lube/sizer for years, then through a Lee push through die once I started powder coating. The only time I had leading in a 9mm, not to mention horrible accuracy and key holing, was when I tried to size at .357. Load them to where they pass the plunk test and don't look back.

[Conditor22]

With the current stat of things in the country and not being able to find a .355 boolit mold does anyone know or has anyone sized a .358 down to .355 to shoot in the 9mm? I have a .358 mold @ 124 Grains. Will this work or do I need to keep looking for a .355 mold??

What 9mm do you have that the barrel/chamber/throat is soo small you need .355 boolits for it?
what boolit are you using?

have you slugged the barrel and/or done a pound cast of the chamber?

I have several 9mm's needing different sizes, the smallest is a Ruger needing .3565 up to a P38 that likes .359-.3595

[ABJ]

I have shot at .358 for 36 years, and it works in every 9mm I own or have owned. As cast, .358 even though it is a .356 mold. I ran them through a Lyman lube/sizer for years, then through a Lee push through die once I started powder coating. The only time I had leading in a 9mm, not to mention horrible accuracy and key holing, was when I tried to size at .357. Load them to where they pass the plunk test and don't look back.

I agree with the above, load the largest the gun chamber will allow. Personally I use 357 only because only a couple of my guns will chamber a 358. All my guns will chamber a 357.
Tony

[Castaway]

Some seating dies will grab a 0.358” bullet, not allowing it to go deep enough into die body and results in inconsistent cartridge OAL. Sizing them to 0.356 allows the bullet to enter the die body unhindered and proper and consistent crimp with repeatable OAL are achieved. I suspect 0.357 would work but have to say I don’t know

[gnostic]

I have shot at .358 for 36 years, and it works in every 9mm I own or have owned. As cast, .358 even though it is a .356 mold. I ran them through a Lyman lube/sizer for years, then through a Lee push through die once I started powder coating. The only time I had leading in a 9mm, not to mention horrible accuracy and key holing, was when I tried to size at .357. Load them to where they pass the plunk test and don't look back.

^^^^What he said without a doubt^^^^

[onelight]

I use both .356 and .357 and can't tell any difference in performance

[Burnt Fingers]

I agree with the above, load the largest the gun chamber will allow. Personally I use 357 only because only a couple of my guns will chamber a 358. All my guns will chamber a 357.
Tony

This right here!

.357 works in every 9mm I've tried it in. .358 can make some of them a bit picky.

[MostlyLeverGuns]

I would try the .358, go smaller only if necessary, then just to .357 unless that does not work, go only as small as necessary for reliable chambering (plunk test).

[Alferd Packer]

I find that if you first size the .358 and lube the rings, then run that lubed bullet thru the .355 die , usually the lube will help to keep the lube rings from wiping off the bullet.
Anyway, give it a try and see what you get.
Upon measuring many sized bullets, I find there is a very slight spring back to alloyed lead. So a bullet sized to .355 and micrometer checked can be .3559 and actually need another trip thru the die to get .355 .
But try loading the .3559 before you run it thru again.
It may be just what the doctor ordered.
Of course YMMV as in anything with machinery or metals.

[Alferd Packer]

I find that if you first size the .358 and lube the rings, then run that lubed bullet thru the .355 die , usually the lube will help to keep the lube rings from wiping off the bullet.
Anyway, give it a try and see what you get.
Upon measuring many sized bullets, I find there is a very slight spring back to alloyed lead. So a bullet sized to .355 and micrometer checked can be .3559 and actually need another trip thru the die to get .355 .
But try loading the .3559 before you run it thru again.
It may be just what the doctor ordered.
Of course YMMV as in anything with machinery or metals.

[gwpercle]

I find .357 sized boolits works just fine in the four 9mm Lugers I have developed loads for .
Make sure they pass the plunk and hand cycling tests ... some "Load Development" in the seating depth area may be required but generally .357 is very doable .
And a lot less effort than going down to .355 ... which is hard on my sizer
Gary

[Darklin]

Ok. Sounds like I need to do some more testing. What I have is a Lee 357 Mold that drops around 125 grains and .358 diameter. I am looking to try and size it down to fit my Ruger P-90 and Spring field XD. XD has tighter barrel than the Ruger. Springfield is at .356 and P-90 is at .3565. I plan to powder coat them so was thinking I needed to drop to .355 for fit. I have a Lee .356 push through so guess I will try that first, Thanks for the info.

[Burnt Fingers]

Ok. Sounds like I need to do some more testing. What I have is a Lee 357 Mold that drops around 125 grains and .358 diameter. I am looking to try and size it down to fit my Ruger P-90 and Spring field XD. XD has tighter barrel than the Ruger. Springfield is at .356 and P-90 is at .3565. I plan to powder coat them so was thinking I needed to drop to .355 for fit. I have a Lee .356 push through so guess I will try that first, Thanks for the info.

Powder coat first. Then size to .357 and you should be fine as far as bullet fit.

I will tell you that that particular Lee mold could cause chambering problems due to the shape of the nose.

[DougGuy]

Of course you can always have the barrels throated for .358" which will let you seat out as long as you want to, provided it will cycle through the magazine. Longer rounds feed like magic.