PMA Neck Turning Tool Question

[Fire4Effect]

I am in the process of turning the necks on .223 Lapua Match Cases. I would like to continue a little past the neck-shoulder junction, but I find I can’t regulate that with the PMA 23˚ carbide cutter for .223. Any attempt to go beyond the neck–shoulder junction results in a wide cut into the shoulder the width of the 23˚ angle. I have very carefully adjusted the turning mandrel depth to creep into the shoulder, but the cut is always the full width of the 23˚ angle. Is there any way to control the width of the shoulder cut with the PMA Neck Turning Tool Model A? Based on a PMA video I reviewed this may be inherent to the design.

In the photo below the progression of the 23˚ cutter can be observed. #1 shows the cutter just before it advances into the shoulder. #2, #3 and #4 shows the cutter advancing into the shoulder minimally. Notice that even though the entire circumference was not cut, where it was cut it is the entire width of the 23˚ cutter. #5 show a full circumference cut with no change in width from #2, #3 and #4.

 

[ronemus]

You need a cutter with a steeper angle than the shoulder (5-10* usually works well); that allows you to cut into the neck-shoulder junction. It only takes a few thousandths to prevent donuts.

 

[jimmymac]

As long as you eased in to it and barely skimmed the shoulder you won’t have any issues.

 

[jimmymac]

Been cutting my cases like that with a PMA tool for several seasons now. Never any donuts and haven’t lost a single neck if that is what you are worried about. My brass gets hammered pretty hard too. High pressure PPC loads.

 

[JEFFPPC]

What Jimmymac says.

 

[PopCharlie]

My 6br cases cut using a pma tool look the same. No issues so far.

PopCharlie

 

[DJSBRS]

FYI, the shoulder height on new brass is NOT exactly the same all the way around. Not uncommon to see that cut on #4. You are right where you need to be. Just don't cut deep into the shoulder.

DJ

DJ's Brass Service

 

[Fire4Effect]

Thanks everyone for the helpful feedback. I did talk with Pat at PMA today and he answered all my questions. Case #5 is correct and I will continue to minimally cut the full circumference of the shoulder. I did my best to try and measure the tailings from the shoulder cuts and it appears that 0.0015” was removed. Pat says I can use 000 steel wool to ease the sharp edge in the shoulder where the 23˚ carbide cutter stopped.

Pat added if I want a tapered shoulder cut he recommended a 30˚ carbide cutter. He is sending me one and I will give it a try. Pat absolutely provides the best customer service.

 

[Fire4Effect]

FYI, the shoulder height on new brass is NOT exactly the same all the way around. Not uncommon to see that cut on #4. You are right where you need to be. Just don't cut deep into the shoulder.

DJ

DJ's Brass Service

Thank you. Out of the 50 cases I cut there are a few that leave a small scallop of uncut material in the shoulder. More than case #4, but not the full circumference like #5.

 

[Fire4Effect]

You need a cutter with a steeper angle than the shoulder (5-10* usually works well); that allows you to cut into the neck-shoulder junction. It only takes a few thousandths to prevent donuts.

Pat at PMA is sending me a 30˚ cutter to try.

 

[bozo699]

Thanks everyone for the helpful feedback. I did talk with Pat at PMA today and he answered all my questions. Case #5 is correct and I will continue to minimally cut the full circumference of the shoulder. I did my best to try and measure the tailings from the shoulder cuts and it appears that 0.0015” was removed. Pat says I can use 000 steel wool to ease the sharp edge in the shoulder where the 23˚ carbide cutter stopped.

Pat added if I want a tapered shoulder cut he recommended a 30˚ carbide cutter. He is sending me one and I will give it a try. Pat absolutely provides the best customer service.

Pat is wonderful to deal with and you can do that with the steel wool but after you fire form your brass it will blend right in, your good to go.
Wayne

 

[mikecr]

 

[BoydAllen]

Funny story, slightly related: Re-turning some 6 PPC brass, with my Stiller turner, the angled part of the cutter is so wide that it cuts across the entire shoulder. Bit of a surprise. Looks kind of cool.

 

[bozo699]

Funny story, slightly related: Re-turning some 6 PPC brass, with my Stiller turner, the angled part of the cutter is so wide that it cuts across the entire shoulder. Bit of a surprise. Looks kind of cool.

It won’t hurt a thing buddy. Hope things are going well Boyd
Wayne