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Neck lathing: Please will you help me re. neck wall thickness

What is your advice re the above-mentioned.

I am neck turning some .308 Lapua Palma cases and in order to achieve total uniformity I am at 0135. Is this too thin?

Many thanks in advance.
 
Neck turning techniques are a personal thing, some people like to turn only about 80% of the neck material and others 100%. I like to turn mine to about 80% and the neck walls end up around .014". If you make them too thin then your brass will develop neck cracks pretty quickly.
 
Thats O K unless you have a custom Chamber. 308's clean up well in that area. Make sure you cut the entire neck without skipping any spots (Concentric Cut).
 
Many sincere thanks for your input!

I bought the RPA 3rd hand and I cannot see any stamping/engraving re. neck diameter.

I have so much to learn!!!!!

Thanks

Cam
If it's a custom , I'd suggest a chamber cast and a check by a good smith . Have him check for safety of course , scope it , check trigger for safe working order , etc .
Don't go crazy about all the reloading gear and techniques. Fire a few factory loadings and measure the fired cases .
You need a starting point , keep records . Once you know what you have , then start on the road to one hole groups
 
Many sincere thanks to you all!

I have been shooting this gun for about 4 months with what I term as fully prepared ammo (bar annealed) cases, i.e. s/s cleaned, primer pocket uniformed, f/l resized, and neck lathed. The neck lathing that I am referring to has been to effect approx. 75-80% of the surface of the neck. This resulted in typical wall thicknesses of .014 to .0145.

On Monday I started some neck lathing on a new batch and noticed that of I did a .0135 wall thickness it effected 100% of the neck surface.

I have now faffed about and got the wall thickness to .014 and 99.99% of the neck is effected. The uniformity of the neck wall thickness seems to bob-on with all the cases I have thus lathed.

I now need to introduce the process of annealing in to my reloading procedure!!!!

Again, many thanks for your patience with a relative newbie to precision reloading.

Cam
 
I suggest you load and shoot some of the neck turned cases to determine if they shoot better than the unturned cases. If they do, then continue to turn them. If they don't shoot better than unturned cases, then do not neck turn.
In my experience, neck turning for use in a factory chamber offered no increase in accuracy. For custom chambers, designed to accept a neck turned case, then it is mandatory.
 
Semi-related question: For a factory chamber, would loading with a smallish bushing followed by an expander mandrel do pretty much the same thing as neck turning? Any variations should be pushed to the outside, leaving the inside of the neck concentric for bullet seating? Variations outside wouldn't matter much as they wouldn't come into play until the neck had released the bullet.

Or is my thinking wrong?
 
Semi-related question: For a factory chamber, would loading with a smallish bushing followed by an expander mandrel do pretty much the same thing as neck turning? Any variations should be pushed to the outside, leaving the inside of the neck concentric for bullet seating? Variations outside wouldn't matter much as they wouldn't come into play until the neck had released the bullet.

Or is my thinking wrong?

first you are at the entrance to the rabbit hole. neck turning to just to uniform the thickness of your necks helps with consistent neck tension and concentricity. your thinking is correct about pushing the imperfections to the outside but....

will your rifle shoot consistent quarter inch or less groups? if not you probably won't notice any difference.
 

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