How does one obtain consistent results when neck turning

[Campbell]

I use a angle drill to turn necks . this drill has a screw through the trigger that regulates the speed . you can see the trigger screw in the pic . I do run it slow . I use RCBS case lube to lube the mandrel . I've never used a cutting fluid on the cutter , I'll have to give it a try next time . I also expand the neck just before the cutting . I only cut a couple at a time , then I let things cool .

I use a De-Walt straight power with only 2 fixed speed settings, but I have not encountered any frictional heat issues even on the high speed setting.

Please would it be possible to give me a photo of one of your turned necks?

Many thanks

Cam

 

[Campbell]

Very good advice above, but in a nutshell, concentrate on:
1. Get several cordless drills that run 150-160 rpms.
2. Use the k&m large heat shrink holder.
3. Lube inside neck with Imperial wax on Q-tip.
4. Expand each case neck immediately prior to turning.
5. Lightly lube mandrel with Imperial wax.
6. Seat case firmly into shell holder, tighten snugly, observe
run-out, re-index case if necessary.
7. Hold Turner on the side that is showing cutter.
8. With very relaxed hold, advance case slowly - watching for a
fine thread or chip. Do not set for a cut over .001".
9. Take your time, I go at same feed rate into shoulder slightly
and out. You must be consistent for consistent results.
10. Spin neck in 0000 steel wool to polish.
11. Use clean Q-tip to remove lube in neck/shoulder completely.
12. Measure 4 sides of neck with ball mic and do the math to see
if clearance desired is right on, adjust cutter as necessary.
13. Repeat, as concisely as possible. Patience and experience
will get you there.

Many sincere thanks for this!

Massage has been cut and pasted into my Excel reloading guidance.

Point 6 is what I have not previously considered and could be the game changer?

Cam

 

[jimbires]

I use a De-Walt straight power with only 2 fixed speed settings, but I have not encountered any frictional heat issues even on the high speed setting.

Please would it be possible to give me a photo of one of your turned necks?

Many thanks

Cam

I don't have a really good clear pic , but here are 3 that I have . I seldom use steel wool , to smooth the finish . these did not get the steel wool treatment .










I found another pic .

 

[Campbell]

I don't have a really good clear pic , but here are 3 that I have . I seldom use steel wool , to smooth the finish . these did not get the steel wool treatment .










I found another pic .

Many thanks

I think my results are similar to yours, but your cutting lines appear to be closer together than mine. I suspect that I may be too eager with my feed-in.

Cam

 

[Mulligan]

Tag

 

[rkittine]

Nice to read through all this. My Short Range Bench Rest Mentor lent me two tools and talked me through practicing expanding and turning some old .22-250 Brass prior to me ruining and good .220 Russian and Pat at PMA tool walked me through all the stuff to purchase, which I am now waiting for. I did how ever buy 50 rounds of pre-turned brass from The Shooter's Corner in orer to get started.

Bob

 

[jimbires]

Many thanks

I think my results are similar to yours, but your cutting lines appear to be closer together than mine. I suspect that I may be too eager with my feed-in.

Cam

yes , if you are to fast moving the cutter you will not get as fine of a finish as these . that's why I like to turn the case slow , I can keep up to it with my cutter feed easier . I'm sure someone has already mentioned that you need to cut down the whole way . I cut down until I just scratch into the shoulder , just enough to know I touched it . this way my cut tends to blend right into the shoulder . just use some old junk brass to practice on . if your good stuff is say 7mm-08 , any junk 7mm brass will be good enough to get the feel of your tools for cutting speed .

 

[Campbell]

yes , if you are to fast moving the cutter you will not get as fine of a finish as these . that's why I like to turn the case slow , I can keep up to it with my cutter feed easier . I'm sure someone has already mentioned that you need to cut down the whole way . I cut down until I just scratch into the shoulder , just enough to know I touched it . this way my cut tends to blend right into the shoulder . just use some old junk brass to practice on . if your good stuff is say 7mm-08 , any junk 7mm brass will be good enough to get the feel of your tools for cutting speed .

Hi jimbires

Are you saying that you prefer a slower rotational turn, or do you prefer a slow feed in?

My instinct is have a high rotational speed, combined with a slow feed-in.

Regarding the surface area of cut, my understanding is that 70-80% of cut/affected area is the recommended.

Many thanks

Cam

 

[jimbires]

Hi jimbires

Are you saying that you prefer a slower rotational turn, or do you prefer a slow feed in?

My instinct is have a high rotational speed, combined with a slow feed-in.

Regarding the surface area of cut, my understanding is that 70-80% of cut/affected area is the recommended.

Many thanks

Cam

I turn the brass slow , I'm guessing 50 rpm . if you look at the pic of my drill I have the trigger screw turned in just about the whole way . then just feed the cutter accordingly , to get a nice finish .

better quality brass cleans up with little brass removal . Lapua and Norma seems to give just about 100% clean up with only cutting .0001 or .0002 ( a tenth or two ).

here are a couple pics of old junk brass I was messing with . if I remember right it was way out . the brass length must have been needing trimmed , I'm not getting the whole way down to the shoulder on this piece.

 

[rardoin]

Hi jimbires

Are you saying that you prefer a slower rotational turn, or do you prefer a slow feed in?

My instinct is have a high rotational speed, combined with a slow feed-in.

Regarding the surface area of cut, my understanding is that 70-80% of cut/affected area is the recommended.

Many thanks

Cam

For a given rotational speed, the slower you feed the cutter tool in/out, the finer the finish you will have. For a given tool feed rate, the faster you rotate the case, the finer the finish will be. The 'ideal' speed and feed is a compromise between heat management from the cutting of the brass and friction of the neck on the mandrel and time management. If I rotate the case too fast I will have increased heat generation which will cause tolerance issues. If I turn/feed too slow, I won't have the patience to turn many cases in a given sitting. Take some brass that is not useful to you and play with turning a dozen necks and see what works best for you.

 

[T-shooter]

To all you reloading gurus:-

I have bought the K&M neck turning kit and have used it thus far on about 100 Lapua .308 cases.

After close examination, I can see very fine "lathe" marks on the neck which nevertheless translate to variances on the concentricity gauge.

I use the kit with a cordless drill on high speed and I use WD40 as cutting fluid.

How do you folk obtain the smoothest cuts?

Many thanks in advance

Cam

I use the same setup with the K&M expander and Lapua .308 brass. I usually take it in one cut but feed the case into the cutter slowly. Just like a lathe, a higher rotational speed and slowed feed give much smoother results. I turn my cases to .0125" wall thickness, never under .0120". Also the flat on your cutter could be not parallel which would give it a point and make it look like it's cutting threads. Are you trying to cut them down to get a smooth surface all the way around?

 

[T-shooter]

I use the same setup with the K&M expander and Lapua .308 brass. I usually take it in one cut but feed the case into the cutter slowly. Just like a lathe, a higher rotational speed and slowed feed give much smoother results. I turn my cases to .0125" wall thickness, never under .0120". Also the flat on your cutter could be not parallel which would give it a point and make it look like it's cutting threads. Are you trying to cut them down to get a smooth surface all the way around?

I should have said I use a 2 speed drill and run it on the slower speed. I take an initial cut, then run it through the tool real slow again for a finer finish. Too much speed will heat up the tool and case too much. The main purpose in turning is equalizing neck tension.

 

[6MMsteve]

Very good advice above, but in a nutshell, concentrate on:
1. Get several cordless drills that run 150-160 rpms.
2. Use the k&m large heat shrink holder.
3. Lube inside neck with Imperial wax on Q-tip.
4. Expand each case neck immediately prior to turning.
5. Lightly lube mandrel with Imperial wax.
6. Seat case firmly into shell holder, tighten snugly, observe
run-out, re-index case if necessary.
7. Hold Turner on the side that is showing cutter.
8. With very relaxed hold, advance case slowly - watching for a
fine thread or chip. Do not set for a cut over .001".
9. Take your time, I go at same feed rate into shoulder slightly
and out. You must be consistent for consistent results.
10. Spin neck in 0000 steel wool to polish.
11. Use clean Q-tip to remove lube in neck/shoulder completely.
12. Measure 4 sides of neck with ball mic and do the math to see
if clearance desired is right on, adjust cutter as necessary.
13. Repeat, as concisely as possible. Patience and experience
will get you there.[/QUOT^^^^^^

 

[Joe R]

Campbel,
Here's a video that shows how I do it. The hand held cutter will wind up sending you the orthopedist if you do any volume at all. I just apply a touch of ISW inside the neck with a q-tip.

 

[T-shooter]

For a given rotational speed, the slower you feed the cutter tool in/out, the finer the finish you will have. For a given tool feed rate, the faster you rotate the case, the finer the finish will be. The 'ideal' speed and feed is a compromise between heat management from the cutting of the brass and friction of the neck on the mandrel and time management. If I rotate the case too fast I will have increased heat generation which will cause tolerance issues. If I turn/feed too slow, I won't have the patience to turn many cases in a given sitting. Take some brass that is not useful to you and play with turning a dozen necks and see what works best for you.

I found an old photo of a freshly turned .308 neck. You can see the finish but there is a lot of glare from the camera's flash. Seems like a smooth finish. I do feed them slow and run a 2 speed drill on slow to keep the heat down but never have used a lubricant on the outside of the necks. I make 2 passes over the surface.

I had a Hornady neck tool for a day but it was beyond horrible and it went back, replaced with the K&M kit with the expander. The pilot of the Hornady tool was smaller at the top than the end and the cases would wobble badly once they were large enough to fit. Also, the cutter was a ground down hardened screw or bolt had a sharp point like a thread cutter.

 

[rardoin]

That is a good finish with a little cut into the shoulder. I would call that a good job.

 

[Joe R]

I had a Hornady neck tool for a day but it was beyond horrible and it went back, replaced with the K&M kit with the expander. The pilot of the Hornady tool was smaller at the top than the end and the cases would wobble badly once they were large enough to fit. Also, the cutter was a ground down hardened screw or bolt had a sharp point like a thread cutter.

Sounds like you're unlucky and got a bad one, or I got lucky and got a good neck turner.



Here's 117 cases, of my 7 SAUM, that I turned just yesterday. I couldn't be happier with the results. It took my about 30 minutes to do them. Try that with the K&M.



By the way, if you don't use lubrication inside your necks or on the mandrel, over 700-1,000 cases, the mandrel will change in diameter because of the wear, giving you more play and therefore more variance in wall thickness. Don't ask me how I know that.

Kindest regards,

Joe

 

[T-shooter]

Sounds like you're unlucky and got a bad one, or I got lucky and got a good neck turner.

View attachment 1010455

Here's 117 cases, of my 7 SAUM, that I turned just yesterday. I couldn't be happier with the results. It took my about 30 minutes to do them. Try that with the K&M.

View attachment 1010456 View attachment 1010456

By the way, if you don't use lubrication inside your necks or on the mandrel, over 700-1,000 cases, the mandrel will change in diameter because of the wear, giving you more play and therefore more variance in wall thickness. Don't ask me how I know that.

Kindest regards,

Joe

The Hornady tool I had was round, not like the one in your picture, and the cutting tool was the end of a sharpened threaded bolt. I see you have the Lock & Load system, completely different. The mandrel was machined like in the picture. The top was smaller and when you had a case large enough to go over the bottom, the top was very loose and you could wiggle the case sideways. One advantage in the K&M is the expander that sizes the neck perfectly for the mandrel. How do you size the necks for your setup?

 

[Joe R]

Neck expansion is a whole other subject that affects not only neck turning but also, and more importantly, neck tension, as in bullet release.

I had been struggling to find a solution to all these neck expansion problems for about a year. I eventually focus on the Hornady bullet puller collet, because that's what I had. I started using pin gages to expand the necks to match the turner mandrel.

However, the bullet puller did not hold the pin gages as co-axially straight as I wanted, so I approached Kenny Porter, who is master machinist for all kinds of things including parts for pacemakers (can you think of anything more critical?). I told him I wanted him to make a die for me that would hold a pin gage, actually a range of pin gages ie .305, .306, .307, .308 and .309. Once I showed him what I had in mind he made a leap to a collet that is ideally suited for what I wanted. The collet holds the cutting bit for a CNC machine. It has real holding power.

Here's what his brain and hands produced:









Now all I have to do is measure the cutter mandrel and I use a Vermont pin gage ($4 on Amazon) to expand the neck to whatever I think its appropriate.

Joe

 

[T-shooter]

View attachment 1010477 Neck expansion is a whole other subject that affects not only neck turning but also, and more importantly, neck tension, as in bullet release.

I had been struggling to find a solution to all these neck expansion problems for about a year. I eventually focus on the Hornady bullet puller collet, because that's what I had. I started using pin gages to expand the necks to match the turner mandrel.

However, the bullet puller did not hold the pin gages as co-axially straight as I wanted, so I approached Kenny Porter, who is master machinist for all kinds of things including parts for pacemakers (can you think of anything more critical?). I told him I wanted him to make a die for me that would hold a pin gage, actually a range of pin gages ie .305, .306, .307, .308 and .309. Once I showed him what I had in mind he made a leap to a collet that is ideally suited for what I wanted. The collet holds the cutting bit for a CNC machine. It has real holding power.

Here's what his brain and hands produced:

Now all I have to do is measure the cutter mandrel and I use a Vermont pin gage ($4 on Amazon) to expand the neck to whatever I think its appropriate.

Joe

A nice setup. It's good to see what a master machinist can do. I may have a use for some of the pin gauges. Didn't know they were that cheap and available. I only turn .308's and the K&M expander works ok for that. The necks are snug enough not to fall off the mandrel but loose enough to easily be turned with my fingers. I use it sometimes as a final sizing of the neck and it produces about .001" interference fit. I run my 208 grain load hot so just little tension works without increasing pressure. I have checked and the tool doesn't move the neck out of alignment. I get the same runout either way. The mandrels are available in custom sizes by special order. The screw bottoms out in the case and prevents ramming the neck into the holder.