Im going to give this a try. I need to rig up some way to punch the primers out now. I could put a smaller dia expander pin in the FL die. I have about 20 pieces of fresh brass that I am about to break out and a whole bag of pieces that have seen 4 firings. I dont think I would turn the necks on that group since I am debating on using them for another cycle or not.
Reducing runout suggestion
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woods
Well-Known Member
Okay, good idea. It got me to thinking.
I just took a FL die out of the drawer for 300 win mag and removed the expander spindle. It sized the neck to .329" with very little runout. My 300 win mag is a factory without a tight neck so I do not normally turn 300 win mag brass. So if this brass is unturned then after firing all the variance in neck thickness is transferred to the inside surface of the neck.
So with a .329" outside neck diameter the math would be .329"-.308"=.021"/2=.0105". If I wanted a .003" bullet grip I would turn then necks to .0105"+(.003"/2)=.012".
The problem seems to me that you want the neck variations on the outside of the neck for neck turning. A very tight mandrel could push the variations to the outside where the blade would cut them but it can be hard to insert those tight mandrels.
So how do you get the neck thickness variations to the outside for neck turning or do you use a reamer?
Winchester 69
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The brass is expanded on one mandrel. A second, smaller diameter mandrel is used when turning the brass. The reamer will not give uniform brass thickness.
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Michael Eichele
Well-Known Member
The post above thisone explains nicley. The first mandrel expands the necks for proper fit in the turning mandrel and when it is shoved inside the neck it forces any variations to the outside of the neck. Or did we missunderstand what you are asking?
woods
Well-Known Member
I'm not sure if you shove a mandrel in by hand that it won't spring back but that is all probably a moot point. I can always just use my Lee Collet first to expand the neck to the right size for my Forster turner, but I was trying to find a way to have a good die in a caliber that does not offer the Lee Collet.
Have you found that all the FL die necks are made perfectly concentric?
Have you found that all the FL die necks are made perfectly concentric?
Winchester 69
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The Forster (and Sinclair) neck-turning mandrels are 0.002" less than bullet diameter. Sinclair has an expander mandrel that is 0.001" smaller than bullet diameter. It fits in their expander body and is used in a press.
Michael Eichele
Well-Known Member
I havent had any problems with any I personally have used. I am sure that there could be some out there that arent up to snuff, but I would imagine most are going to be very straight. They are resizing dies after all.
woods
Well-Known Member
Yeah, just looking for a way to get started with this method. All the new cases I have bought have been too tight to accept the Forster hand held outside neck turning mandrel. If you know already the neck diameter of the die then that helps but you still have to turn the necks to use this system. With new cases the neck is too tight for a mandrel, after firing the neck is too big and after sizing they are too small again, for the neck turning mandrel that is.
So I guess you have to buy an expander mandrel and expander body to expand the necks of new brass so that you can get the neck turning mandrel in. Cheaper to buy a Lee Collet Neck Sizer which will expand the necks in new brass just right for neck turning. But then you have a Lee Collet Neck Sizer and don't have to buy a FL die and don't have to neck turn unless you have a tight necked chamber.
I can't find the expanders on the Sinclair website but did find it posted where the expander costs $18.50 and the mandrel $8.50 and most FL dies run $25.00 so that is $51.50. A Lee Collet cost $17.00 and a Redding Body Die cost $22.00 so that is a cost of $39.00 to do the same thing.
A good thing to know for the next caliber where Lee doesn't make the Lee Collet though.
Have y'all ever run into a FL die where the inside diameter of a FL die was so small that you had to turn the necks below .010"?
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Michael Eichele
Well-Known Member
The sinclair expander mandrels are very straight and uniform and would work prefectly for your situation. They are not very expensive when you consider the good job they do.
I use them for a few different calibers. I just run them through the expander mandrel and they fit perfectly on my turning tool. I also used the mandrel before seating and it works like a charm. No additional runout. In fact the mandrel in perfect to use if you WANT to use something after neck sizing with a bushing.
I use them for a few different calibers. I just run them through the expander mandrel and they fit perfectly on my turning tool. I also used the mandrel before seating and it works like a charm. No additional runout. In fact the mandrel in perfect to use if you WANT to use something after neck sizing with a bushing.
Chuck Boyer
Active Member
Hornady has a concentricity tool and dial that is new. I found it on the Hornady website using the search word concentricity under reloading. I heard that Hornady claims that the tool measures and corrects runout. Does anyone have any experience with this tool or know how it works?
