Greetings Everyone:

I need to resize some 148gr HBWC from .358 to .356 for a Sig Hammerli P240. What would be a good brand to have for this purpose? I don't plan on casting my own bullets so this will be used for resizing only and probably not for lubing. Thank you to all.

This works with your reloading press. Around 18 bucks at Midway and other places -

Lee Precision: Lube & Sizing Kit

Pardon the curiosity, but what caliber are we discussing?
According to my catalog, the pistol is only produced in the following calibers: 38 SPL WC, 32 S&W long and 22lr.

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Science plus Art

This will be for .38 special. The Lee kit might just be the ticket.

If the pistol is chambered for .38 Special use the .358 bullets as-is. Even if Sig used a .356 (standard 9mm) dimensioned barrel it is because using the smaller barrel does not cause any problems with standard ammunition. If you expect to improve accuracy by sizing the bullets to .356 you are very likely to be disappointed!

The Hammerli name is renowned for accuracy. Don't you suppose if the precise barrel dimension was critical to accuracy that they would be building their pistols with .358 barrels?

You are trying to solve a non-existant problem.

I have to agree, if it's a 38sp, then shoot 0.358" bullets. I can;t imagine Sig makes the bores 0.355" like the 9mm for a 38sp. Bore dia should be 0.357", you want to be 0.001" min. larger for best results.

i cast and lube size often. on 38sp. without slugging the bore of your gun to get the correct dia. i would go .359 you want to be 2 thosands over bore dia. if not you will get gas cutting and leading as a result. incorrect dia. of a bullet is what causes most leading and poor accuracy. i shoot 30-30 and 32 win. special rifles with soft cast at around 1800 fps with almost no leading at all. remember size matters!

Manufacturing requires that dimensions have tolerances. While a .38/.357 barrel is nominally .357 inches in groove diameter, manufacturing tolerances allow .356-.358 as acceptable.

Factory ammo will have similar tolerances-at least for lead bullets. I once bought a bulk load of 2K major manufacturer 158 gr .38 Spl RNL slugs and was startled to discover they were .360 inches. They shot just fine.

I agree with the folks who suggest you give the slugs you've got a try before creating work for yourself. If you find you might need a smaller slug, the Lee kit seems a cost effective way to confirm this (BTW, if you resize, you'll have to relube) before you start shopping for a bulk load of bullets of the correct diameter. There are sources who produce bullets of smaller diameters as a regular product.

The groove diameter of the barrel is .352 +.002" and the bore diameter (between lands) is .342 +.002" You can find pictures of the barrel on the internet. It is unusual looking.