How many neck turn brass?

FrancF

For constancy? (I am just trying to get the ball rolling) [:D]





NRA Life Endowment Member

ZERODIN

Never tried it, but I'd like to get into it. Anything I can do to put every hundredth of a minute of angle variation on me and off the gun and load, I would like to do (within budget constraints).

JustC

Guilty[:D] I even do it on some factory rifles[:0]

why chase the game when the bullet can get em from here?....
Got Balistics?

FrancF

quote:Originally posted by JustC
Guilty[:D] I even do it on some factory rifles[:0]

why chase the game when the bullet can get em from here?....
Got Balistics?


I don't have a custom chambers, But I will do it if I am doing the bear min on neck sizing.





NRA Life Endowment Member

ContacFront

I don't......YET.

Justin, is it worth it on the factory barrels/chambers?

Kdub

You're really wasting time turning necks for commercially chambered rifles, providing you aren't using another cartridge and either fireforming or die swaging them. Commercial chambers are cut with enough slop to allow slightly thicker necks as you reload and the brass flows. Just watch your trim length and the incepient separation near the base.

Now, if you have custom chambers, especially in wildcat cartridges that have been custom reamed, then it's a whole new ball game. These chambers aren't normally reamed/throated to SAAMI spec's and are tighter in all respects. Here, slightly thickened necks can mean excessive chamber pressure.

For those of you insisting on turning case necks for factory chambers, be aware you can take too much off and have a neck so thin it won't provide adequate friction hold on the bullet. This causes inadequate combustion of the propellent and lousy exterior ballistics. The case necks, shoulders and often the case body will be excessively smokey. If you trim any at all, do so with caution.

That said, brass does not flow evenly when stretching with firing. The buildup in the neck will normally be heavier (thicker) on one side than the other. Don't insist to get that "engine turned" look all around the case, unless you specifically want to radically reduce the neck thickness.

Keep off the Ridgeline

JustC

Kdub,..I control mu neck tension with the use of Bushing dies. If/When I turn necks for a factory chamber,..I am only turning the high spots off so that I can get runout down to a good .002" and maybe an occasional .0035". The bushings size the neck down to any size I want by the .001" increment so sizing after measuring the slightly modified necks thickness tells me which bushing to buy based on how much tension I want. I will usually order 3 bushings,...003" .002" and .001" tension. So a .284 pill plus a turned neck of .0135" thickness will be at zero neck tension at .311",..therefore I order the .308", .309' and .310" bushings.

Neck turning for factory chambers is largely useless. Like I said,..I do it to keep the "feel" for my gear so when I prep BR brass,..it is a reflex action and I am more apt to run through the process with more efficiency. My NK tunring in HB factory rigs with bushing dies will start to show it's merits at 300yds and beyond. A smaller neck will no doubt increase the expansion dimension between the neck and the chamber wall in the neck area,..but by increasing the NK tension,..better internal case burns can be acheived. This plus seating a bullet to touch the rifling will make up for any increased neck/chamber clearance (albeit only maybe .001" total when cleaning off hgh spots on the nk)

Bottom line,..LR shooting means splitting hairs, even in factory chambers. Turning necks without bushing dies will necessitate you chucking the expander ball in a drill,..and runnning it over some FINE emeory paper to reduce it's size,..therefore it expands the neck less and makes for the same result as smaller bushings in bushing dies. BUT,..the expander can never be made bigger for a new batch of brass.

why chase the game when the bullet can get em from here?....
Got Balistics?