Turning Necks On Wildcats

[Clucknmoan]

For example with a 7/300 or a 6x47, is it best to turn your necks when the case is in the parent form or after it's necked down? I would assume it's best after it's necked down, especially if you are targeting a specific neck thickness.

Thanks gents.

 

[Bullet bumper]

I polish inside the necks first .
The first fit you need is a neck internal ID smaller than the expander mandrel .
The internal neck size you need next is to fit neat on the turner mandrel.
There is a few ways you can do it and all work out about the same .
If the new cases are already too large for the expander mandrel then you do need to size them down in a die and then expand them back up to the turner mandrel fit .
Once you cut some off the neck diameter, any standard neck size die is not going to work well anymore so once you start neck turning it is best to move to other dies like bushing or Lee collet die .
I use a Sinclair neck expanding die with a mandrel that once used leaves the internal neck ID just right for the Turner mandrel to fit snug without binding up. It's a parallel expander mandrel and goes all the way inside the neck .
I also use some dry lube inside the case neck if things get a bit tight to turn .
Once turning is done then I go about case prep and sizing to load the case .
The order of when you do the case prep can vary.
You can't do a good smooth accurate neck turn without a snug fitting turner mandrel and a slow patient style .
There's a lot more to the whole process but that's a quick reply .

 

[Frank in the Laurels]

I have a rule on factory cut chambers, their loose enough ! The more I take off the worse it gets so why bother....it just gives more room to stretch and let seems case life... On custom cut chambers, as tight as I can make em', my Borden cut 6PPC is .262...a loaded round before firings is .261 and some change, now I mdon't shoot it at max and I have never lost a case due to splitting..

 

[Bullet bumper]

There is ways to use neck turning on a factory chamber you just have to know how .
It centers around using partial length neck sizing in future . That regains the neck in chamber fit tighter than before neck turning . I invented it for myself and the body die about 30 years ago as I'm sure many others did in those days of no internet , no info , no custom stuff , no special dies and no place to buy much .
It's not a cure all for a rotten shooting gun that has other accuracy issues. Fix those issues first so you can then actually see slight improvements on the target .
Go to this thread page 2 you will find a lot of info on this subject . http://www.longrangehunting.com/forums/f28/28-nosler-neck-turn-not-185259/index2.html

 

[Clucknmoan]

Should have been more clear I guess. Not asking about "if" I should turn these necks or "how" to turn them, just asking at what stage. These aren't factory chambers I'm talking about. As far as the equipment I use, Redding comp bushing dies and K&M neck turner/expanding mandrel.

In a 7/300 WM, you start with the parent case of a 300 WM and then neck it down about .010 at a time with a bushing die unless you have a custom 7/300 WM die built. Either way, same same. At what point does it make the most sense to turn your necks? When it's in the parent 300 WM state, or after you have necked it down to the 7MM state?

I would say it makes more sense to turn the neck after its in the final 7mm state, especially if I am after a certain thickness for a desired clearance in a tight neck chamber or if you are just after a specific neck tension and are short on bushing sizes. I would think that necking down .024 (or so) in this case would change the thickness of the neck wall some if I had first turned at the 300 WM state.

This has always been my line of thinking but I've recently heard a few other state differently. Anyone have experience with both processes?

 

[IdahoCTD]

It's best to turn them as the parent case so part of the neck becomes the shoulder and reduces the chance, or delays it, of forming a doughnut. If you have to do a small clean up on them after they are the correct caliber to get the correct dimensions, that's pretty easy to do. Case necks do get thicker as you neck them down.

Probably the most right answer is to turn them thin enough to get them to work in the chamber but leave them a little tight, neck them down, fire them, and then clean them up to the clearance you want once the case is fully formed to the chamber.

 

[Pdvdh]

It's best to turn them as the parent case so part of the neck becomes the shoulder and reduces the chance, or delays it, of forming a doughnut. If you have to do a small clean up on them after they are the correct caliber to get the correct dimensions, that's pretty easy to do. Case necks do get thicker as you neck them down.

Probably the most right answer is to turn them thin enough to get them to work in the chamber but leave them a little tight, neck them down, fire them, and then clean them up to the clearance you want once the case is fully formed to the chamber.

Yup. My experience also. I agree with this logic and recommendation.

 

[Mikecr]

I turn them in parent form, new out of the box/bag.
It's simply trial & error, turn, size, measure, do another & another until right.
This is a use for cases culled for various defects. You should be able to dial it in by 5-6 cases.

 

[Bullet bumper]

It's hard to say which way would be the best you may have to experiment with a few cases done each way and see what you end up with.
I would tend to lean toward turning after the necking down is done then you could seat some bullets and see how much thickness you are really working with .
See how good the inside neck surface is after necking .

 

[TOM H]

If your going to do it before then you need 30 cal mandrel and expander, bushing to neck it down. Your still going to need 7mm mandrel and expander maybe some more bushing.

Myself I might make one cut at 30 and final at 7mm.

 

[Bullet bumper]

When you neck down any inconsistencies in neck wall thickness on the outside go to the inside of the neck . So Tom H's idea of doing a light skim at 30 cal is not a bad idea . Should result in a better inside neck surface at 7mm . As long as total thickness allows for it . Experimentation is required on a few of the worst looking cases before you settle on a process .

 

[newmexkid]

I'm working on some Lapua cases for my .20 Practical. I found that, (as suggested already) that doing a light skim prevents, (for me) the mouth of the case forming a "bell" during the down-sizing of the .223 case. Then I load a dummy round and use the appropriate bushing to get me at least .002 less then my chamber.