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Help me with a tool list to get my necks and mouths perfect with no runout.

ChrisBCS

Sergeant
Full Member
Minuteman
Feb 8, 2014
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The cartridge in question is a .30-06

Doing some measuring with simple caliper gauges, these case necks are not perfect thickness around. Some of them also have collet marks at the very top from trying to neck resize when they had been too cold worked, they should have been annealed first or simply tossed.

The case mouth also has hills and valleys, in other words it's not a flat circle perpendicular to the centerline of the cartridge.

So to eliminate the first problem, I need the correct mandrel diameter for .308, and a good outside case neck turning tool, correct? Will I also need a neck expander to make the case neck open to fit the mandrel in? What neck thickness do I want to shoot for?

To eliminate the second problem, do I simply need case trimmer?

Thanks!!
 
How much neck expansion are you getting from a fired case? You find this out by measuring from sized with a bullet seated to the fired case. More than .007" and it's probably not worth turning necks because much more neck expansion than that + the .002" turned off and now there will be .009" expansion. You can turn off less than .002" but I think the most benefit is from a full clean up of the neck. I've had stock rifles before getting .010" expansion, what I learned is the greater the neck expansion the sooner and more often the necks start spitting.

Also a very good idea to use all the same brand and lot # of brass to begin with.

The case trimmer is primarily for case length, you'l need one for that purpose.

I mostly use K&M tools for convenience and cost. This tool has a micro adjust which makes it easy to adjust cut depth. You'l need the expander die and expanderon to go with it. I like the carbide cutting mandrel with reamer for taking care of donuts while turning necks, this is beneficial for necked up or necked down cartridges you might try later on. I also have a Pumpkin neck turner for my 6x47L, the mandrels and the tool itself are expensive though.
 
Not to rag on you, but you are shooting a sporter weight barreled 30-06, you are over thinking this.

Start with fresh brass, trim to length, chamfer once and shoot the brass 4 or 5 times...repeat.

To help avoid run-out get a dead length seating die. I seat partially, turn the round a 1/2 turn the seat the rest of the way, turn the round again and work the ram again.
My redneck R/O test is to roll it across a mirror an watch the bullet tip.

Seriously buy the book "The Accurate Rifle" by Warren Page...you will thank me.
 
Not to rag on you, but you are shooting a sporter weight barreled 30-06, you are over thinking this.

Quite intentionally. It's not so much the rifle, I'm interested and obsessed now with learning the hows and whys of handcrafting accurate ammunition!
 
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Steve, thank your post. I need to digest it and do some of the measurements. I do need to measure how much neck expansion I'm getting. After resizing I'm getting 0.3065" ID at the mouth. The main thing I think I want to get rid of is the vertical "wobble" of the case mouth circumference.
 
First, as a matter of perspective, I don't know that it's possible to make perfect case neck/mouths unless you cull those that aren't perfect. Individual cases vary too much for that and they harden a little with each successive use but, it IS possible to make them better. But making necks better isn't just a matter of buying the right tools, if that were true everyone would be using the same things - and they don't. Fact is, there are several equally effective tools to TURN, TRIM, FORM necks and they all do very well IF used correctly. Loading skill comes from knowing what we're doing and it's a learned thing, we can't spend enough money on tools to avoid that truth.

I could tell you what I do but all you would then know is what I do, not what effect it has on my accuracy, much less what it would do for you. I can tell you for a fact that seating part way and rotating the case to finish does nothing helpful, once a bullet starts off axis it will stay off axis because no seating die stem is so tightly fitted in a die that it can do a thing to fix runout no matter how you turn the case. It's the last few thou that are hard to fix and that last bit is so tiny it sure isn't visible on rolling ammo! And I can promise you that if you can see any 'wobble' at all on a rolled round the runout is awful. Perhaps the best "first" accuracy tool is a good runout tester, Sinclairs gage is about as good as any and the lower cost dial indicator is fine. A decent neck turner IS helpful if it's used properly; Forster's Hand Operated Turner (HOT 100) will do all anyone but a competitive BR shooter will need. But unless you're already consistently shooting sub MOA groups, sweating perfect run out is meaningless. And a lot more "all day long 1/2" groups are fired from a keyboard than a firing line! If you're shooting a factory rifle and chamber you could load 'perfect' ammo and never see any difference from pretty good necks with 2-3 thou of real run out anyway. (A LOT of people don't even know how to measure bullet run out correctly, never mind know how to fix it,

The biggest things most new accuracy seekers need to do is learn how to trouble shoot their rig and learn to shoot and learn to develop a really good shooting reload. Eventually, loading skills should improve but there's no quarantee of that.
 
Thanks Fuzzball! Very good stuff. I've read that post several times over. Awesome information. Seems like many aspects of hand loading for accuracy have a "dark art" quality to them, simply from the amount of misinformation floating around.