Home Forums Reloading Big Game Rifles Necking up .308 Win

Got a rifle on the way to JED for a rebore to 338 Federal. While it's out I figured I'd neck up some 308 Win brass to 338 Fed.

Any special that I should pay attention to? is a tapered expander necessary?

Dies are Redding. Candidate brass is both new Winchester and some 1x Hornady.

Should be able to do it without any issues.Lube the inside of the necks well helps a lot.As long as the brass is soft it should be easy,so new and once fired should be OK.

I have necked to 35 for a 358 using Lyman dies. Not a tapered expander. Nowadays, I do it in 2 steps using 32 Spl and then the 358. Lots of lube and steady pressure.

Dale

Over the years I've necked up a variety of caliber cases with the largest span being necking up 7 mm RUM brass up to .375 RUM in one stroke.

Most size die expander plugs have too short a taper for large expansions, so using my poor man's lathe (an electric drill, a metal file, and a thread cutting die) I've made a variety of expanding plugs for a Lyman M-2 die. I use a liberal amount of Imperial Size Wax and even the 7 mm to .375 expanding is smoothly done with almost no lost cases.

Mr. Expand-O-Matic.

Surely, you're not recommending sizing wax on the expander, or are you?

CH4D make some pretty cool gadgets for molesting brass

CH4D

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Nice. I'll have to check my Redding dies and see what the thread pitch is on the decapping rod.

I have done it from 308W to 338F in one step. No issues really. The neck might be a bit short but not terribly so. I used both LC match brass and RP brass. I did not lose a single one.

This was the standard method to make brass for the .338-08 before Federal put their name on it. It's an easy resize pull of the lever and you're good to go. Never had any issues. I have a bunch of once fired .338 Federal brass from a trade but have never used any of it.

Simple and cheap: If you have a Lee decapping die, which lotsa reloaders have on their bench, you can buy different sized expander plugs to use in it. Get a .338 plug, snap off the decapping pin, and just plunge away! I did that with hundreds of cases of LC 7.62x51 for .358 Win and LC M2 ‘06 cases for .35 Whelen before final sizing with the respective RCBS dies.

^^ Good info

Is that thing turning .300 WMs into .416 Taylors?

Not on the expander, but on the inside of the case mouth. Size Wax or any other lubricant reduces the friction between the brass and the steel surfaces.

If you're sizing down the outside of the case, you put lubricant on the outside of the case.

If you're sizing up the case neck, you put lubricant on the inside of the brass.

I lubricate the inside of the case neck by wiping my finger over the wax, then pull and twist the case mouth over the lubricant on my finger which puts a small bead of wax just inside the the case mouth.

Lee sizing wax in the tooth paste type of container, applied to the inside of the neck works wonders, better than Imperial sizing wax. Also, put a heavy chamfer on the inside of the case mouth.

Long tapered expanders make this process easy. Redding sells long tapered expanders, and the std hornady dies have a long tapered expander. Std ball type of expanders are more apt to kink a neck way out of alignment resulting in WILD-NON uniform necks....I can not stress this enough.

Pro Blend Assembly lube used by engine rebuilders to lube bearings also works well, but like most petroleum products, you are going to have to "wash" the cases in a de greaser, where the Lee lube, you just ignore, load and fire.

Blasphemy !!!