Cast bullet sizing.

[Texas10mm]

ah.... so cast lead should be .358" for 357/38sp which are .357" when jacketed, then safe to say cast lead should be .357" for 9mm which are .356" when jacketed?? I'm mostly trying to understand why the sizer for .357" exists, if lead should always be .358." Also, obviously, hoping to find a use for (justify) something I bought, cuz I hate wasting anything (I'm snail-trapping and remelting my bullets), and cuz I didn't really research it enough when I picked that one and that's a little embarrassing.

9mm bullets are normally .355, however MANY 9mm handguns have oversized bores. I've seen some that a .356 bullet will fall through.

Normally you want your lead bullets to be 0.001-0.002 over bore.

http://www.lasc.us/Fryxell_Book_Contents.htm

I highly recommend reading this book.

 

[Thornapple]

.357 sizer can be used in 9 mm. You could use it in 38 if you size before powder coat. I would prefer to use the larger sizer after powdercoat for the best consistency.

Thank you... I know all this information is Out There, but with so many opinions it's challenging to separate them from actual information. I'm interested to see if I can get a second coat of powder to stick to the slugs I've already PC'd... and I agree: going to get a larger one once I determine whether I should get .358" or .359."

 

[Texas10mm]

Thank you... I know all this information is Out There, but with so many opinions it's challenging to separate them from actual information. I'm interested to see if I can get a second coat of powder to stick to the slugs I've already PC'd... and I agree: going to get a larger one once I determine whether I should get .358" or .359."

Have you slugged your bore and measured your cylinder throats?

 

[Thornapple]

Yes, you can use an inertial bullet puller on loaded ammo. That’s what it was designed for. I put a small cotton ball in the bottom of mine so it doesn’t deform the tips of pointy jacketed bullets.

The proper size for a cast lead bullet is really determined by the size of your barrel. A general rule is to shoot them as big as will fit into the chamber reliably, and no smaller. Bullets that are too small allow hot gasses to blow by the base and that is the primary cause of leading. I size 9mm bullets as large as .358 and 38/357 as large as .359. How large are they when they drop from the mold? You might even be able to get away with shooting them unsized if your gun has fairly large throats.

I haven't even been bothering with sizing until I got a 6-cavity Lee... I haven't mic'd them but some shove through the .357" sizer with nearly no resistance, and some (from the same mold) come out with the lube-grooves approaching smoothed - I suspect those are the ones I assembled into cartridges that wouldn't chamber in my blackhawk, 77/357, or s&w m.60 or m.10.

9mm bullets are normally .355, however MANY 9mm handguns have oversized bores. I've seen some that a .356 bullet will fall through.

Normally you want your lead bullets to be 0.001-0.002 over bore.

http://www.lasc.us/Fryxell_Book_Contents.htm

I highly recommend reading this book.

Thank you; Website bookmarked and clearly labelled!

 

[Thornapple]

Have you slugged your bore and measured your cylinder throats?

*kicks dirt*
noo.....

 

[Thornapple]

Have you slugged your bore and measured your cylinder throats?

*kicks dirt*
noo.....

I've checked to be sure that the .357-sized bullets aren't too tight in the cylinder throats, but Slugging the Bores sounds more involved than I might be ready for... though TBH I haven't researched that one as until now I haven't seen the need show itself in any barrels after shooting. I've been trying/hoping to find the one size that works for everything, but I'm coming to understand that this just isn't How It Is. Which is fine, too... I'm loving this hobby after a year+ of involvement, and as long as I'm involved I expect to swirl deeper down this particular rabbit hole.

 

[frankmako]

to find out what size of cast lead bullet you need you should slug the barrel. then go one up on the size. so if the barrel slugs at .357 then size at .358. home powder coating can add some size to your bullet. i cast my bullets, powder coat them, then size them. except when i gas check them, then i like to size/gas check them before i powder coat them.

 

[Thornapple]

I found this from 1911 forum, from Bruce381 in 2012:
(regarding procuring a slug appropritely oversized to use for this slugging the barrel operation. Seem good to those listening? An inertial bullet puller will pop the lead that's been poured straight into a case??)

"...easiest way to make 'slugs" is to use an empty fired case of the caliber you want to test.​

(should I consider doing this with a case fired in each gun I'm measuring, or would this be A Bit Much?)

Like take a old 45 acp case pour or melt SOFT lead into the case I heat the case with a propane torch to melt the lead fully, let cool and use a boolit puller to pop out the "slug"
this will also have a taper on one side due to the case shape and the taper end is what you start into the barrel reasl easy once you have done it. Also note that heating the case with a torch will really soften it so I crush and throw away that case csue i do not want o load it by mistake and have some kinda problem."​

 

[Thornapple]

9mm bullets are normally .355, however MANY 9mm handguns have oversized bores. I've seen some that a .356 bullet will fall through.

Normally you want your lead bullets to be 0.001-0.002 over bore.

http://www.lasc.us/Fryxell_Book_Contents.htm

I highly recommend reading this book.

This is the best pile of casting information I've seen yet! Thank you for the link! Lots of detail transmitted clearly even to a person who's much better at geometry than metallurgy.

 

[Bugster]

I have a few bottles of the Lee liquid alox and I have used it with no leading. But it does have a smell to it, it's petroleum based. I powder coat now and I like it, but the alox is here for back up.