Sizing down from larger diameter a good idea?

[dmclark523]

This may be a simple question but It's been bugging me lately.

I have two 9mm, a SCCY CPX and a FN-FNS.

Bore diameters are a little different, with the FNS being slightly over-sized. The question is,
if I get a mold that drops at .358, would it necessarily be a good idea to size down
to .357 for my CPX, and shoot the FNS at .358?

For the time being, under I can afford a lubesizer, I'll be pushing them through Lee sizing dies.
Anything I should know or be aware of before going through with this? Will it be very difficult,
gum up my die, ect?

[dmclark523]

Nobody? Just curious if this is really a good idea or not. I'd really like to not have to purchase two separate molds at different diameters...

[williamwaco]

I have scrapped my 4500 Lubrisizer in favor of Lee push through dies.

Most shooters here size the 9mm to .357 or .358.

I would try .358 in both guns.
If they chamber and the action locks up with no "help" from you.
They will be fine.

If they will not chamber, you will need to go to .357.

[paul h]

No problem sizing down 0.001-002" The lee push through sizer's work great, many of us started out with them before getting a lube sizer.

I prefer not to size more than 2 thousandths as the more you size the greater the chance you'll size unevenly and the lube grooves and canalure start to dissapear.

[Shiloh]

I'd leave it at .358. For me, .358 is that cats meow. .357 is good, .358 noticeably better. It is a scarce 9mm pistol that has a bore of .355. I shoot traditional lube grove boolits sized at .358 for consistency and lubed with alox lube with wonderful results.

Shiloh

[cbrick]

It'll be fine to do that in a LEE push through. A tip, don't size them dry, either lube the boolits first or use something like Hornady's Unique case lube, just small amount on your finger tips as you handle the boolits to put them in the die is all it takes.

Rick

[jhalcott]

The 9mm is one caliber I RARELY load for. I have to borrow dies to do it. But when I do I slug the bore before sizing the bullets too small. I slug the bore before I load cast in any new to me gun. Sizing down a few .001 isn't that big a deal, but IF they'll shoot as cast, it's usually better.

[Green Lizzard]

i size down 358s to 350 for a 348 win in two steps. they shoot fine

[rintinglen]

I size 358-429s to .350 for my .348 winchester no problemo. A thousandth or two means diddly when sizing, but means a lot when matching boolit to bore.

[runfiverun]

I gotta say sizing down is a whole lot better idea than trying to size up.
try the 358 size in both guns.
if you measure some brass you will find some is thicker and some is thinner this gives you the opportunity to separate cases by head stamp for each gun.

[1Shirt]

One of the beautiful factors of shooting cast boolits is being able to size down when required.
1Shirt!

[dmclark523]

Thanks for all the opinions everyone. Definitely not worried about it anymore!

[GLL]

If the bullets are "round" sizing down is not a big problem using the LEE die.

These BRP bullets dropped at 0.462" and were sized down (in several steps) to 0.454" for .45Colt.
http://www.fototime.com/F2B9D5B8B8FEF9C/orig.jpg.

This is testament to the quality of Bruce's molds and his machining ability ! :)

Jerry

[Bret4207]

Still turning out boolit porn, eh Jerry?;)

[GLL]

Still turning out boolit porn, eh Jerry?;)

No, this is just old porn rehashed ! :) :)

Jerry

[Bret4207]

They age better than regular porn stars!

[Char-Gar]

I shoot and have shot .358 cast bullets through over a dozen various Euro and American 9mm handguns plus an Uzi carbine with good results all around. Therefore I see no reason for the OP to size to different sizes for his two handguns.

.358 is .358 and it matter not what type or brand of sizer is used to get to that number.

[Screwbolts]

I have the CPX also and I load using Lee dies, I size to .359 using the NOE 358-135 RG4, This chambers and shoots just fine in my CPX2.

[mikeyman]

I have a 9mm 1911 that I slugged at .354 which seems wrong but I have checked several times using a micrometer. I guess I will have no choice but to size down!