30-338 case forming (or necking down in general)

[DougH9]

OK, I gave up on trying to to use 300 Wins for my new 30-338, and got some new 338 cases to neck down. Problem is, when I run them through the sizer (Redding FL), the necks come out horribly crooked. I tried different lots, and even once fired cases (found at the range)...same result. I thought that maybe my die was bad, but the reformed 300 Wins are straight, and if I fire a crooked round in my rifle, it comes out straight, and then re-sizes straight.

I thought necking down was a simple operation. I do not want to have to depend on fire-formed brass.

Can anybody help me here?

 

[Bart B]

Doug, from what you're saying, I don't know enough to help you. But here's what I've learned from wearing out four .30-.338 barrels.

Necking down Winchester .338 Mag. cases in my RCBS or Bonanza full-length sizing dies has always been easy. My dies' necks are lapped out to about .3350-inch diameter so I won't have to use the expander ball for reloading fired .30-.338 cases. I lightly lube all the outside of the new unfired cases, then run them through the die using a .3085-inch expander ball. That makes the case mouth a snug fit on my neck turning tool's .3080-inch mandrel so I can turn the necks a bit.

I've used Winchester and Federal .300 Win. Mag. cases to make the long-neck version the same way.

About your problem, remove the decapping rod and expander ball from your full-length die, then size some .300 Win. Mag. and some .338 Win. Mag. cases. See if their necks are straight. If they are, your cases with bent necks were probably made that way by the expander ball. Next time, clean the fired .300 Win. Mag. and .338 Win. Mag. cases' mouth with a bore brush on a drill. Then lightly lube the mouths inside using a cotton swab. Finally full-length resize these prepped cases and see what happens.

If you could explain in detail exactly what you're doing to set up the die and size the cases, that might help me help you.

 

[DougH9]

Bart...you nailed it! I am in your debt! I just made some brass with the expander ball removed and it is straight. Now that I think about it, the 300 Win formed brass that I made (that was straight), I made with no expander ball (because it takes a few steps), and then I expanded with my Hornady 300 Win die (because it has a tapered expander). I just did not put the two together.

So what do I do now...is my die bad? Contact Redding?

Thank you VERY much Bart, for putting me on the right track.

Doug

 

[TOM H]

The 7 mag is just a 338mag case necked down to 7mm. I just got a 30cal expander and neck up 7mag cases for both my 30-338 mags alot easier than neck down 338mag brass work the brass alot less. Just my .02.

 

[DougH9]

thanks Roper. I tried 7 mags also, and with the Redding die they came out crooked. I tried some with the Hornady die (300 Win.), and they were fine.

I really want to use shortened 300 Win cases so that
I can set the shoulder where I want it on the first fireing, and so that I can run a longer neck. My chamber will accept a case OAL of 2.525" (neck makes contact at 2.537"). This gives me a nice long neck, and protects the chamber a little.

I ordered a Forester neck turner today, so I will give them another try.

But the lesson of the day is: Check to see that your expander is centered in your die. When I twirl this die in my hand, the ball is way off center. I checked my other dies, and except for another Redding (in 300 H&H), they are OK. I will be contacting Redding about these two.

 

[TOM H]

When turning necks you need a Forester pilot also good to use an expander ball that will push the brass to the outside of the neck. Sinclair sells expander ball for redding dies also handle the expander and die needed to turn necks. When you get to turn neck good thing get is an inside neck reamer. Alot of the 30-388 were chambered with a 308 norma mag reamer which gave a longer neck, body was something like .0002 longer and OAL case was 2.2559. Depending on how they set the headspace you wind up with a longer neck. My first 30-338 the guy used one of those reamers my next ones build I made sure the use a 30-338 reamer and case OAL was at 2.500. You can still buy 308 Norma mag brass it's pretty high dollar stuff but save you alot of work and trouble. Well good luck