Neck turning???

[smokin_gunn2]

From my measurements I should only have to take a couple thousands off to true necks. I was worried about trimming length. .005 under trim to length would not be to much?

 

[BrentM]

From my measurements I should only have to take a couple thousands off to true necks. I was worried about trimming length. .005 under trim to length would not be to much?

A couple of thousands is a lot for what you are doing. It's hard to measure unless you have very high end calipers or micrometer to measure neck thickness. I'd trim the cases to the shortest length and set your neck turning depth to kiss the shoulder. I'd start with the cutter just barely skimming the surface and run 5 cases. One of the five will likely have a very obvious neck wall divot and I'd plan to clean that case to 95%. I'd rerun the other 4 and would expect .005 removal with a total of about .001 off the outside diameter.

 

[smokin_gunn2]

I have a Redding case thickness gauge. Sorry a couple thousands is my variation if I turn to true only need .001 to skim necks to within a thousands. I never turn the necks completely. Should be in the .015 to .016 neck thickness when done.

 

[misterc01]

I measure the neck thickness with a ball mike for consistency. If it measures the same at four points 90 degrees apart - top, bottom, left right. I don't turn.

 

[30BR]

That's what I was going to do but once fired brass is under trim to length already. I was hoping to prep all brass at once but I guess not with this brass. Just have to batch prep and hope for the best.

On first firing, the brass may have blown out to fill a slightly large chamber. I've seen some brass actually shorten on first firing. Usually by the third firing they are good to go.

 

[Rflshootr]

Or you could just skim turn the longest ones that measure the same length. Load 'em & shoot 'em to see if it made a difference. I find Lapua is always within .001 on neck wall thickness. So I shoot for about 2/3 to 3/4 clean up.

 

[smokin_gunn2]

I was kinda thinking along the same lines. Thought about trimming some and not others and shooting some two hundred yard groups just to get zeroed and see what happens. I am working up some other loads for a different gun also so kill two birds with one stone.

 

[Litrfoot]

I wanted to turn necks on my lapua brass but it's under trim to length already. Should I trim shorter to even out? Just curious on what is to short? My 6.5 CM brass length is 1.906- 1.910. Once fired. Most is 1.907 and 1.908. What to do?

Don't do anything.! Shoot it. You are way under the MAX trim lenght 1.920..

 

[corsteve]

just shoot it trim later dont hurt to be a little short been doing this for 40 years an had no problems

 

[smokin_gunn2]

42 more new brass to fire form, be enough to shoot 100 yard tall test then some 200yd zero and groups. Just trying to have once fired brass prepped and ready for some fine tuning of the load. Thanks for all the suggestions.

 

[tnek13]

The neck tools I have use the case mouth to index the cutter to determine the length of cut towards the shoulder. The neck needs to be the same length on each piece of brass not the overall length of the piece of brass. I use a Little Crow trimmer that indexes off the shoulder. At one time I was annal and turned everything, today not so much. Measure everything first, if you must turn then trim first.

 

[BrentM]

42 more new brass to fire form, be enough to shoot 100 yard tall test then some 200yd zero and groups. Just trying to have once fired brass prepped and ready for some fine tuning of the load. Thanks for all the suggestions.

Off topic I know, sorry, but I would like to understand this one. Tall test is your scope tracking test I am assuming and hoping. If not, what is your tall test for?

 

[smokin_gunn2]

Yes you are correct. Installed new level on scope just double checking it before stretching it's wings.

 

[Blackhawk]

I wanted to turn necks on my lapua brass but it's under trim to length already. Should I trim shorter to even out? Just curious on what is to short? My 6.5 CM brass length is 1.906- 1.910. Once fired. Most is 1.907 and 1.908. What to do?

Short Answer to your dilemma
I believe that you are simply talking about your brass cases over all length (OAL) and not enquiring about the turning of your brass case necks themselves correct?
Trimming of your brass OAL (overall length) is one thing !
Refer to any recipe book or Saami Specs first !
For Saami specs your 6.5 Creedmoor brass hulls should not exceed maximum OAL = 1.920"
For Saami Specs your 6.5 Creedmoor brass hulls s trim to brass case length is OAL = 1.910"

You can use your brass which is now -.002" -.003" under minimum OAL but I would reduce my powder by -5% .
These loads will fire form themselves to you chambers dimensions as you use them
After you have shot these rounds..
Examine all brass hulls after use and make certain all is well before proceeding further !
Deprime brass and tumble clean as per your norm.
Next after FL resizing pay close attention to your trim to case length, as I find it quite questionable that any brass would come -.003 short from the factory.
I suspect that the error is on your end in trimming your brass to length (see Below)
I say this in order to help you not criticize you.
To that end ( & we all have done this )
Before re trimming your brass to length , readjust your trimming tool to allow +.003" longer case length after your next firing to bring your brass OAL to the 1.9.10" trim to length
Please re check your dial /digital caliber zero as well as your trimming tool, and adjust your OAL as needed. before you start to trim your brass shell cases.
If you have already trimmed your brass, and find that they are - .003" under minimum O.A.L.,
you can go ahead and use this brass. However I would load my powder at a reduced rate of -5% from maximum powder load.
Simply mark theses cases with a sharpie pen and be aware of the reduction in powder as you use them.

Now turning of your Brass cases necks is a different story all together !
Hope this will help you!