Loading procedures

[Kevin Stenberg]

I have decided to outside neck ream some of my brass. Calibers are 30/30, 06, 308
I know that you are reaming the necks of all cartridge cases to be as uniform as possible. To determine what measurement to take the necks down to. Would you use a tubing mic. measure say 5 cases at 4 locations each around the full dia. of the neck. Say you get the lowest measurement of .016 and a High measurement of ..0186. And all of the rest of the measurements fall in a bell curve between the high and low. What thickness would you ream all of the necks to.

 

[Rick]

Inside neck ream. Outside neck turn. Depends on what your shooting these cases in, not a lot to be gained from NK turning in the average hunting rifle and the thinner you make the necks the looser they fit the chamber. Turning necks is mostly a bench rest technique in rifles accurate enough to see minor gaines in truing up the necks. Also for very tight match chambers to allow the brass to chamber with a bullet seated. Yes, a tubing mike is the correct tool, never with calipers.

 

[Ian]

Like Rick wrote, the inside is reamed (rarely and for different reasons than the average person with the average rifle will every see the need for) and outside turned. The most you will ever need to do on a commercial cartridge in standard chambers is uniform the neck thickness by taking off some of the thick side of the neck to uniform the thickness. This involves removing the bare minimum of material and often the cutter will only contact about halfway around the neck.

You will likely never see the benefit of turning .30-30 necks even though they are often 0015" or more out of whack. -06 and .308 will see some benefit, especially the military brass, but the benefit is small unless you are pursuing above-average velocity with accuracy.

There is a major drawback to outside-uniforming case necks and that is it takes one or two firings to bring the center of the neck back to the center of the case body and shoulder, so it's best to do the turn on once-fired brass before full-length resizing (this may require a custom turning mandrel) and pretty much count the next firing as a waste as it fireforms and moves the neck back to the middle. After you check outside concentricity following this fireforming, you may be able to neck-size only at that point, but if the necks still aren't centered, another go with the FL die (maybe backed off the shell holder 1/16" or so) might be in order to further correct concentricity. Once the neck is back to center, you can use a neck bushing die at that point and get maybe two-three firings before needing a light anneal, or "draw". Typically, you will need to bump the shoulder back each firing by about .0015" to relieve bolt thrust pressures, so a bushing neck, shoulder-bump die (Redding makes one) is good for maintaining your brass after you get it turned, trimmed, and fireformed.

Overall, there is a lot more that can be done to improve groups before you get to the point that neck turning will show much improvement in groups. I put it near the bottom of the list, along with flash hole deburring and lube tweaks.

 

[fiver]

never mind that.
where are you getting brass that's .0016-.0018?

 

[Rick]

never mind that.
where are you getting brass that's .0016-.0018?

I wondered that, possibly measured with calipers?
.

 

[Ian]

I don't think he measured any yet and was throwing out numbers as an example. If he did measure it, he used calipers and didn't remove the crimp or serrations from the case mouths. Never seen '06 or .308 that was more than .0135" after turning off the high side, usually it's about .012-13".

 

[fiver]

I was kind of excited for a second there.
I got ahold of some thicker 243 brass last year, I'm still working on fire forming it.
I hate shooting it because the groups suck and I can't stand to look at them.
but it will work out in the long run.

 

[Ian]

I was kind of excited for a second there.
I got ahold of some thicker 243 brass last year, I'm still working on fire forming it.
I hate shooting it because the groups suck and I can't stand to look at them.
but it will work out in the long run.

Have you tried knocking the high side off some LC 7.62 necks and taking it down in stages (7mm-08, then .260 Rem FL size, then .243 in a bushing neck sizer)? I did a few hundred for a friend who shoots jacketed and got uniform necks about .015", which was about as much as was safe for jacketed bullets in his rifle.

 

[GaryN]

I would have to agree with what has been written above. I went through a pile of brass with a very accurate rifle in the 80's. Turned all the necks. Couldn't tell any difference. Groups were really good before I turned the brass. Maybe that was as good as I could shoot.

 

[fiver]

the thicker brass gets the bullet up in line with the barrel better.
most factory rifles have a lot of room cut in that area, thinning the necks makes it worse.

my problem is same load, less capacity.
knew it would happen, but it's not the load they are for and the bullets are [were when I bought them] cheap.

I thought about the 308 conversion and even have 500 LC cases from the same lot sitting in a can.
but I got a good buy on some once fired 243 cases [like 16 cents each] and then found these SSA's and figured I'd give them a try [kind of like the good sunday suit stuff]

the rifle isn't new or guilt edge but it will shoot when fed the right stuff.
okay it's more a beater truck rifle with enough accuracy for 200+ yd varmint eradication and the occasional opportune deer or yote.
but I got a couple of butt ugly rifles that will shoot even after being drug through the mud and rocks, or laid down in the snow for a while.

 

[Kevin Stenberg]

Ian was correct I just picked the # in my example out of the air.
I think you guy's helped me make up my mind. Anyone need a Forster Outside Neck Reamer with pilots for .311/.286/ .308 new unused LOL

 

[Ian]

Just the outside turning attachment, or the whole shebang?

 

[Rick]

I would keep it Kevin. It's a high quality and very useful tool, it does much more than just NK turn. Length trimming as one example. I have two of them, one set up for length trimming my most used match brass and the other for everything else.

 

[Intheshop]

There's a lot of technique and feel involved with getting repeatable measures with any mic.IME,tubing mics are even more so.It's because of the anvil shape.It takes practice.

Having said that,gotta say ...the cheap ___ brass that has come through here of late,has been so accurate,that you are almost as likely introducing error using consumer grade turning tools.

Look for one of those old panavise's.Put your mic in the jaws(they're plastic) ,now you can concentrate on holding the case,and getting proper geometry.The ability to adj the vise gets as user friendly as possible.EBay.

Also keep an eye out for a B&S,bench...0-.5 mic.You'll know when you see one...just sayin.100$ used,with box would be a decent price.

 

[fiver]

a lot of what happens to our brass is induced by the press we use, and how we set it up.
and quite a bit by how we operate the ram.
just the act of seating a bullet can set it in there crooked.
and seating it all in one swift motion doesn't help.

I have taken to using 3-4 strokes to fully seat a bullet.
a partial seat then a turn then a partial seat then a turn, and finally a seat and another turn for a second full seat.
I rarely see .005 in runout even with cases like the 257+p cases I necked up and fire-formed in the 7 Mauser.
it doesn't make the old Ruger a 1/2" rifle by no means, but it does settle things down enough for it to be consistently under an inch with the occasional 3-4 shot 1/2" group.

why I don't get all worked up about neck turning is because I rarely use a bushing for neck sizing.
all the inequality in the case gets pushed in when you outside size and pushed back out again when you pull it over the expander ball.
now if you are going to turn necks you need to use a bushing fitted to that case thickness to set neck tension and you also need to keep a consistent anneal to really take advantage of the system.
if your rifle isn't capable of taking advantage of the thinner fitment efforts then your just creating more work for yourself.

the other consideration is if your brass is off enough to need turning in the neck area that same thickness flaw runs the whole length of the case.
if it varies from case to case, your capacity varies too, maybe less/more than 1-2%.
but you weighed your charge weighed your bullets and fit everything, then knowingly introduced a variable.
using store bought primers is enough variation.

I would rather spend my time trying to find the center line of the barrel with the centerline of my bullet.
the gun will deal with things from there and I can work on finding a barrel node to tighten things further.

 

[Ian]

thickness flaw runs the whole length of the case.

Yep, and will show up later as a half-donut at the inside base of the neck from shoulder brass creeping forward and play hell with the technique of using the outside base of the neck to do your cartridge/bore alignment chores. Something to watch.