Neck turning.. fast vs slow, does it matter?

[ohiohunter]

Kind of new to reloading and even newer to turning necks. I've used the sinclair chuck in my dewalt and with blazing speed I can turn my necks. I've also come across guys saying to turn them slow, does it really matter? I'd hand turning them would leave small stop/start marks, and turning slow takes for ever. Whats best and why?

 

[FearNoWind]

I prefer to turn slow to prevent any possibility of galling the inside of the necks. But not so slow that it becomes an agonizing chore. Scars in the neck surface are usually caused by slight misalignment when the mandrel first enters the neck. But it's not usually a big deal - depending of course on how deep we let the cutter run. If you're leaving start/stop marks you may be trying to cut too deep in one pass.

 

[LoneTraveler]

When it come to metal turning of any type several things matter. Type of Metal being cut. Bit rake angle and cut angle on tool. In facing say a 14 inch circle of metal on a lathe as you cut from the inside out you would have to stop and slow the lathe down to get a smooth cut. It is not so much revolutions of the material as it is how many feet a minute the bit is cutting. Find a speed that give a smooth cut and stay with it. also check the inside of the neck and be sure to not gald the inside of the neck, You would have to use a lube and then clean the cases. Good Luck.

 

[Gene]

Fast or slow is not really the criteria. I turn with a K&M shell holder and Craftsman cordless screwdriver, & MAP gas. Keep the flame about 1" away from the neck. Turn until an orange color develops on the neck. NOT RED. As soon as the orange color reaches the neck-shoulder junction, drop the hot case ointo a metal pan. I do not drop mine in water. When I start with a full charge on the Craftsman, turning takes about 5-6 seconds. Count them 1001, 1002, etc. until you see orange at bottom of neck. That helps with subsequent annealing.

IF YOU MAKE THE NECKS RED HOT, THE CASE WILL NOT BE ANNEALED, AND IS TOAST. If not orange, you have under annealed. You can also buy Tempalac to measure temperature. I don't use it anymore, I just count seconds.

 

[Tumbleweed]

Fast or slow is not really the criteria. I turn with a K&M shell holder and Craftsman cordless screwdriver, & MAP gas. Keep the flame about 1" away from the neck. Turn until an orange color develops on the neck. NOT RED. As soon as the orange color reaches the neck-shoulder junction, drop the hot case ointo a metal pan. I do not drop mine in water. When I start with a full charge on the Craftsman, turning takes about 5-6 seconds. Count them 1001, 1002, etc. until you see orange at bottom of neck. That helps with subsequent annealing.

IF YOU MAKE THE NECKS RED HOT, THE CASE WILL NOT BE ANNEALED, AND IS TOAST. If not orange, you have under annealed. You can also buy Tempalac to measure temperature. I don't use it anymore, I just count seconds.

The OP is asking about neck turning or removing brass by cutting the o.d. of the case neck. What you're referring to is annealing.

 

[Tumbleweed]

When I turn new brass, I chuck it in a 3/4" chucked drill press. I tend to turn it a little on the fast side for a really smooth, uniform cut. This also produces heat faster. So, I either use engine oil (dip the case neck in it before cutting) or spray really soapy water in the case neck before cutting and on the case neck as I'm cutting. Both seem to work fine but the soap and water method keeps the heat down better. Get some automotive brake cleaner and spray your cases out when done, at least if you use the oil method.

 

[Gene]

The OP is asking about neck turning or removing brass by cutting the o.d. of the case neck. What you're referring to is annealing.

Too many cobwebs in the remaining few brain cells.

 

[Unofficial Gun Addict (UGA)]

Man... I'd rather go fast than slow when turning necks... But i usually go..... Ready for it.... Medium! Turns out nice and uniform... Smooth... And consistent when measured. No galling.

 

[Deleted member 46119]

A machinist will tell you it's all about speeds and feeds.

I use a Forster Original, I crank pretty fast but the goal is to make one long "chip". That will always be the smoothest most consistent cut.

Then keep turning very fast and back out slowly for a "finish" cut.

 

[Canadian Bushman]

The appropriate SFM to cut brass with HSS is pretty high ( aprx. 2-300 sfm / 2300-3400rpm for a .330 dia). Your limiting factor in this case it the heat generated by the brass spinning on the mandrel.

Brass heat soaks very well and will get hot in a hurry if spun too fast or not lubed properly. When the brass starts to get to hot it will swell causing increased friction on the mandrel and inconsistencies in neck thickness.

Your best bet is to size the brass just a few ten thousandths under the diameter of the mandrel, run at about 300-500 rpm, and use a generous amount of heavy oil or case lube.

I personally do this in a Bridgeport mill, with the case chucked in a collet, and i run every case twice.

If i could figure out how to post a video i would show my setup.

 

[ohiohunter]

Well I certainly don't have a mill to turn necks hahahaha, but I'll keep at it how I'm doing it w/ the ol' 12volt dewalt and forester hot turning tool. I'll make sure I keep some oil handy, I usually spray the pilot with some one shot. Do you think the one shot will work on the outside of the case too?? or something less messy that cutting oil?

 

[Canadian Bushman]

I dont mean you need a mill to turn your cases, just that they need to be turned at a timely pace and done so consistently so the cutter can perform that way as well. If you can do this with your drill than youre good to go.

In my experience, the messy oils that are stubborn to remove are usually the best ones.