Neck Turning - Inconsistent Results for a Newbie (Video)

Stangs55

Stangs55

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Jan 26, 2010
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#1
I dove head first into neck turning this week...but I'm not getting the consistency I want...

I decided to take the plunge after I measured the neck thickness on my Lapua brass to range from 0.0140 to 0.0165 on the same round. I'm really just looking to clean up the neck tightness and not to fit a tight chamber.

So I bought a new K&M Carbide Pilot/Carbide Cutter, K&M 30 cal expander, and K&M power shell holder/driver directly from K&M....and then watched/read everything that I could on the subject.

I'm starting off turning 3 times fired Lapua brass after wet tumbling -> annealing -> FL resizing -> trimming -> expanding with K&M mandrel

I guess my first surprise is the amount of brass wobble seen when the power driver is fitted to a drill. Looking at YouTube videos, my wobble seems very consistent with what other are seeing...I just wish it was straight (and can't help but wonder if this is where the problem is).

So the issue is this: say that I measure my neck thickness of a single Lapua brass to be 0.0140 - 0.0160 and I decide to trim to 0.0140. So I walk my cutter in and lock it down prior to each turn. My issue is that over 50% of the time, I'll end up with brass that started as 0.0140 - 0.0160 to be 0.0135 - 0.0150. The median may be around 0.0140...but the variability across the neck of the brass seems way to large. It's clearly cutting the brass all the way around....it's just not uniform. I've tried super low speeds with the drill and faster speeds...nothing seems to work. I've tried taking as long as 45 seconds to make one antegrade pass...nope. I've tried 4 or 5 total passes....nope.

And while it may not seem like a huge variability and that I have achieved what I wanted by tightening it up a bit....it's far from what I expected. I also just picked up a Redding Type S neck sizer and some Ti bushings....so having a consistent neck it going to be very important when I select which bushing to use.

So I guess I my questions boil down to:
1. What kind of consistency are you guys getting when you neck turn? Are you seeing your brass very concentric +/- 0.0005 after turning?

2. I know it's hard to say...but is there something that people who are new to neck turning typically do wrong when starting out that leads to these inconsistencies?

3. Or is this just an acceptable range for a K&M turner and a power drill....would any other brand produce better results?

4. How do you deal with the brass wobble when holding a drill in one hand and the turner in the other...I've been holding the turner relatively loose allowing it to kinda oscillate up and down with the brass wobble in an effort to keep the pilot very centered....should I be doing this another way?

UPDATE: Video of my process....tell me what I am doing wrong!
Neck Turning Brass - YouTube

UPDATE TWO: Video of turning at a much slower speed and measurements right before and after turning as requested below...
http://youtu.be/2h9OvVdatR4

UPDATE THREE: Final test using new brass and a braced drill...
http://youtu.be/yjoL9Phr7o0
 
Last edited:
#2
Hmmmmm ... I've had very good luck with the K&M systems and I have all the tools you do except I use a different case holder in the drill. I used to turn using a hand drill then migrated to a drill press. You should not see the amount of wobble you are describing but even with the wobble you should get very uniform neck wall thickness. This link will show how I do it when I make 221 Fireball brass from 223 cases. Maybe you can Pick up something from the pictures. FWIW - I like high RPM when turning.

I finally got around to it - 223 to 221 Fireball (pic heavy) - Shooters Forum
 
#3
flashhole said:
Hmmmmm ... I've had very good luck with the K&M systems and I have all the tools you do except I use a different case holder in the drill. I used to turn using a hand drill then migrated to a drill press. You should not see the amount of wobble you are describing but even with the wobble you should get very uniform neck wall thickness. This link will show how I do it when I make 221 Fireball brass from 223 cases. Maybe you can Pick up something from the pictures. FWIW - I like high RPM when turning.

I finally got around to it - 223 to 221 Fireball (pic heavy) - Shooters Forum
Click to expand...

Thanks for the feedback.

The amount of wobble I'm talking about is essentially the same as is seen in this Sinclair video at 45 seconds in...although a different driver of course

Sinclair Case Holder and Driver - YouTube

I'm thinking about just making a video of my process and uploading it for critique and I'm kinda at a loss where the problem is...
 
#4
Is there slack between Mandrel and inner neck as you slide case in? Or, is it very much snug as you slide case neck into mandrel?
I use Sinclair NT 4000

I turned 50 338 Lapua cases two weeks ago.
Before: 0.0140 to 0.0165
After: 0.0130 to 0.0135

I had very little wobble but it was noticeable.
How clean are your cuts?

When I first tested on practice brass I noticed I had too much clearance between mandrel and inner neck. Cut result was poor. Once mandrel to inner neck was snug I was good to go.

A few quick thoughts...

sent via Tapatalk
 
#6
Tristian19 said:
Is there slack between Mandrel and inner neck as you slide case in? Or, is it very much snug as you slide case neck into mandrel?
I use Sinclair NT 4000

I turned 50 338 Lapua cases two weeks ago.
Before: 0.0140 to 0.0165
After: 0.0130 to 0.0135

I had very little wobble but it was noticeable.
How clean are your cuts?

When I first tested on practice brass I noticed I had too much clearance between mandrel and inner neck. Cut result was poor. Once mandrel to inner neck was snug I was good to go.

A few quick thoughts...

sent via Tapatalk
Click to expand...

flashhole said:
Triston makes a good point. The expandiron is supposed to size the neck to the proper size for the reamer or pilot. You might measure there first.
Click to expand...

It seems pretty snug to me...it's a carbide mandrel and I really don't feel that there's a need to lube the pilot....dunno if that means it's too loose?

How do you adjust so that it's "snug"....seems like you just buy the mandrel from the manufacturer and expand....

Cuts seem clean.

Video incoming...
 
#8
I didn't watch the video. 3g is slow where I'm at, anyhoo, just curious about the wobble. Do you have a concentricity gauge to measure runout before and after sizing. The again after expanding? A lot of times, expanding can induce runout if you are taking the neck up quite a bit or aren't using enough lube. Lube those insides liberally. Just a thought to ponder.
 
#9
No lube is needed for a carbide mandrel.
Lube IS needed if NOT a carbide mandrel.

I have no PLAY between case neck and mandrel during neck turn process.
I'm
Snug comes from neck sizing followed by expander.

Out with fam. Have not watched video yet.

Just another quick thought or two...

sent via Tapatalk
 
#12
At first I thought you did not neck size before expanding but after just rereading your original post you mentioned you did FL.

I've never used K&M unit but I have only heard good things about it. Only reason I went with Sinclair NT 4000 over K&M was to be able to make smaller cuts.

Thought:
Take ALL measurements of case(s) before and after each stage. Neck thickness, inner and outer diameter (before and after necksize, expanding, everything). I am not understanding how/why you are obtaining results you are. Probably something small and stupid. I am known for doing such.

sent via Tapatalk
 
#13
I'm not an experienced neck turner; only a few years going.

With that being said, as I understand it...

Wobble from one source is generally necessary. I.e. Pumpkin neck turners require wobble, as part of the off center design. The wobble I see from the video is too much.

My initial neck turning trial runs, I had issues with breaking necks and consistency due to:
Neck turner not being in a clamp
Running the drill too fast

I'm not in love with that case holder. Is it plastic? Sinclair makes a great one, although expensive.
 
#14
Fester47 said:
Instruction say,

If you choose to turn the cartridge under power it is best to choose a cordless screw driver which typically have lower max speeds than a drill. Turning at high speed will generate heat which will effect dimensional control and risk galling brass onto the pilot.

K&M Shooting - Micro-Adjustable Neck Turner Complete with Carbide Cutting Pilot, Carbide Cutter, and Shell Holder
Click to expand...

Lol... I KNEW that I should have done this after I finished the first video. You are absolutely correct. I've seen that most people seem to turn at much higher speeds than what K&M recommends with good results, however.

Regardless, I should have done this in the first video as it is per K&M's recommendations...so allow me to present a second video where I turn at much slower speeds. Of course in doing so, this has made my point even further as I now end up trimming the brass down into the 0.011x range! And all this without changing the cutter depth from the previous video when it was trimming to 0.014...!

(I'd like to also propose that all "What am I doing wrong?" posts from here forward on the Hide are accompanied with a video :) ...It makes it easier for me to explain what I'm doing and you to see the nuances in the process.)

https://www.youtube.com/watch?v=2h9OvVdatR4&feature=youtu.be

TireMan said:
I'm not an experienced neck turner; only a few years going.

With that being said, as I understand it...

Wobble from one source is generally necessary. I.e. Pumpkin neck turners require wobble, as part of the off center design. The wobble I see from the video is too much.

My initial neck turning trial runs, I had issues with breaking necks and consistency due to:
Neck turner not being in a clamp
Running the drill too fast

I'm not in love with that case holder. Is it plastic? Sinclair makes a great one, although expensive.
Click to expand...

I've been eyeballing that Sinclair case holder...I'm not against expensive! But I am against inconsistent! If people seem to identify that K&M case holder wobble as an issue....I'll be the first to place an order at Sinclair!

Tristian19 said:
At first I thought you did not neck size before expanding but after just rereading your original post you mentioned you did FL.

I've never used K&M unit but I have only heard good things about it. Only reason I went with Sinclair NT 4000 over K&M was to be able to make smaller cuts.

Thought:
Take ALL measurements of case(s) before and after each stage. Neck thickness, inner and outer diameter (before and after necksize, expanding, everything). I am not understanding how/why you are obtaining results you are. Probably something small and stupid. I am known for doing such.

sent via Tapatalk
Click to expand...

See the above video. I measured right after expanding and then right after turning. I can't measure outer diameter right now as my outside micrometer has yet to arrive...but it will soon. Thanks for the advise. :)

"Something small and stupud" <-- THIS! This is what I'm expecting is wrong! K&M is clearly a reputable brand with plenty of very satisfied users who have excellent results...which is why I'm posting these videos! I'm assuming that the problem has to be with me! I'll never claim to be the best at anything...I'll only claim to be willing to learn!
 
#15
Stangs55 said:
Lol... I KNEW that I should have done this after I finished the first video. You are absolutely correct. I've seen that most people seem to turn at much higher speeds than what K&M recommends with good results, however.

Regardless, I should have done this in the first video as it is per K&M's recommendations...so allow me to present a second video where I turn at much slower speeds. Of course in doing so, this has made my point even further as I now end up trimming the brass down into the 0.011x range! And all this without changing the cutter depth from the previous video when it was trimming to 0.014...!

(I'd like to also propose that all "What am I doing wrong?" posts from here forward on the Hide are accompanied with a video :) ...It makes it easier for me to explain what I'm doing and you to see the nuances in the process.)


I've been eyeballing that Sinclair case holder...I'm not against expensive! But I am against inconsistent! If people seem to identify that K&M case holder wobble as an issue....I'll be the first to place an order at Sinclair!



See the above video. I measured right after expanding and then right after turning. I can't measure outer diameter right now as my outside micrometer has yet to arrive...but it will soon. Thanks for the advise. :)

"Something small and stupud" <-- THIS! This is what I'm expecting is wrong! K&M is clearly a reputable brand with plenty of very satisfied users who have excellent results...which is why I'm posting these videos! I'm assuming that the problem has to be with me! I'll never claim to be the best at anything...I'll only claim to be willing to learn!
Click to expand...


If this is old non usable brass then keep playing but if good usable brass then I say STOP and give K&M a call firs thing Monday or as soon as you can. Something just is not right.

Just to confirm your cutter pilot (Mandrel) is Carbide, correct? And not your EXPANDER being carbide!

I took close look at how snug your case neck appears when sliding into pilot. Appears as mine.

Are all these cases from same case lot? If so, do you have any other cases from different case lot? <<< Long shot as I am digging now!

Not sure if following will make sense in explanation or in practice.
Do you have different color Sharpies? My thought is to lightly mark on case area neck sizes before and after you neck size. I assume a pre 0.0165x would be post 0.0145x if a pre 0.015x is a 0.013x. Purpose would be to make sure uniform decrease. Just another thought. IF, above was not true then I would be bangin' my head even more.
 
#16
In the video I think your spinning the case too fast, I spin them just a tad slower than in the Sinclair video.

Something to ponder would be are you taking measurements consistently, for example the same distance from the mouth of the case around at different intervals? Not sure if that would vary.

I use a Sinclair Turner and the wobble is normal, don't fight it. It's comes from the drill gearbox. Just let it wobble in your hand and feed it into the cutter at a slow constant rate. Go the same slow speed when you're backing it out. After the operation my necks vary about half a thousandth or less. I think that's about as good as one needs without removing any more material than you have to. It takes me probably 1 min per case.

The case neck should fit kind of snug on the mandrel, I wouldn't describe it as a loose fit or having much play. Just tight enough so it can still rotate.

Also, try doing this with the drill on its side instead of pointing up, I think it is easier to control the feed that way.
 
#18
I second the thoughts above on making sure that you don't have any measuring error. You may consider using the Redding case neck gauge which measures at a consistent point on the neck.

I am relatively new to neck turning as well, and I use the 21st Century neck turning lathe. I get turned necks that are within 0.0005 all the way around.
 
#19
I don't think anything is wrong with your equipment, K&M has a good rep. I use a Sinclair tool and shellholder and I get some wobble too, probably from the drill. I set a plastic bowl (hospital puck bowl) on my lap, hold the drill horizontal in my left hand and hold the tool in my right. I run the drill fairly slow, about 250-300 rpms, and crowd the feed fairly slow and as smoothly as can. I work the cutter into the shoulder a few times and finish up with a touch of 4/0 steelwool. I'm holding my tolerance to about .0005 with my technique.

A couple of thoughts for you; 1. try bracing your drill and cutting tool on something, like your knees.
2. try crowding your feed a little slower and try to be even and steady.
3. run the cutter up and down the neck a few times and then hit the cut with steelwool.
4. you might try a drop of oil.
5. save some old brass to us for tool set-up and practice.

Hope some of these thoughts help, Good Luck.
 
#21
What does the inside of the turned neck look like? You might try cleaning it with a bore brush when chucked up in the drill. I clean the inside of my case necks prior to turning.
 
#22
OP, I was in the same exact boat as you. Started out with a K&M turning kit to use on Lapua brass. Here's what I discovered - you'll get much better results using the ergo holder in conjunction with simply doing it by hand. I didn't get consistency using a drill either.

Since I bought 500 Lapua cases, hand turning all of them wasn't going to work for me. I ultimately purchased the 21st Century Lathe, and get much better & faster results. The good news was that I could reuse my K&M arbor & expander mandrel with their adapter.

It was an expensive lesson for me, but made life much easier (well at least with regards to neck turning). Check out their video on youtube
 
#23
Alright....I'm videoed out....final video using brand new brass and the drill in a vice...

Neck Turning Brass Part 3 - YouTube

Tristian19 said:
If this is old non usable brass then keep playing but if good usable brass then I say STOP and give K&M a call firs thing Monday or as soon as you can. Something just is not right.

Just to confirm your cutter pilot (Mandrel) is Carbide, correct? And not your EXPANDER being carbide!

I took close look at how snug your case neck appears when sliding into pilot. Appears as mine.

Are all these cases from same case lot? If so, do you have any other cases from different case lot? <<< Long shot as I am digging now!

Not sure if following will make sense in explanation or in practice.
Do you have different color Sharpies? My thought is to lightly mark on case area neck sizes before and after you neck size. I assume a pre 0.0165x would be post 0.0145x if a pre 0.015x is a 0.013x. Purpose would be to make sure uniform decrease. Just another thought. IF, above was not true then I would be bangin' my head even more.
Click to expand...

Pilot and cutter are carbide. K&M does not offer a carbide expander that I am aware of...

lightman said:
I don't think anything is wrong with your equipment, K&M has a good rep. I use a Sinclair tool and shellholder and I get some wobble too, probably from the drill. I set a plastic bowl (hospital puck bowl) on my lap, hold the drill horizontal in my left hand and hold the tool in my right. I run the drill fairly slow, about 250-300 rpms, and crowd the feed fairly slow and as smoothly as can. I work the cutter into the shoulder a few times and finish up with a touch of 4/0 steelwool. I'm holding my tolerance to about .0005 with my technique.

A couple of thoughts for you; 1. try bracing your drill and cutting tool on something, like your knees.
2. try crowding your feed a little slower and try to be even and steady.
3. run the cutter up and down the neck a few times and then hit the cut with steelwool.
4. you might try a drop of oil.
5. save some old brass to us for tool set-up and practice.

Hope some of these thoughts help, Good Luck.
Click to expand...

Thanks for the suggestions. I think I addressed these in the above video.

flashhole said:
Is your cutter installed properly. The cutting bit has a taper on it. Make sure it is not in backwards.
Click to expand...

It's not. Thanks.

flashhole said:
What does the inside of the turned neck look like? You might try cleaning it with a bore brush when chucked up in the drill. I clean the inside of my case necks prior to turning.
Click to expand...

Clean. The above is brand new brass. I even cleaned it in an ultrasonic cleaner to get all the dry neck lube out after FL resizing...

Mike402 said:
OP, I was in the same exact boat as you. Started out with a K&M turning kit to use on Lapua brass. Here's what I discovered - you'll get much better results using the ergo holder in conjunction with simply doing it by hand. I didn't get consistency using a drill either.

Since I bought 500 Lapua cases, hand turning all of them wasn't going to work for me. I ultimately purchased the 21st Century Lathe, and get much better & faster results. The good news was that I could reuse my K&M arbor & expander mandrel with their adapter.

It was an expensive lesson for me, but made life much easier (well at least with regards to neck turning). Check out their video on youtube
Click to expand...

Noooooo....don't tell me that :( I'm afraid that I'm steadily arriving at the same conclusion. The K&M may work...but where is the consistency? And how much of this do I really have to go through for each piece of brass? I don't mind something taking time to do right...but I do mind it if it's not the same between cases...

I headed over the 21st Century to see what it would cost to get a rig for turning my 300 WSM, 308, and 300 RUM.... The total comes to $400.36... Ouch. There's a spot for a coupon....anyone know of any in case I decide to go this route? I wonder if K&M will return the turner since it's only a week old...
 
#24
It looks to me like there is too much clearance between the case necks and mandrel. I can't get brass over the turning mandrel unless it's lubricated and turning. If the bit was moving, it'd only move out.

I also only turn for 60-80% cleanup and wind up with less than 0.000 5" variance if I discard anything that doesn't get turned that much. The turned part varies less than half that. I'm using an older Sinclair turning setup and a case holding setup like yours. I do 223 directly in the drill chuck. I still have .0015 - .002" neck tension after turning. I use Imperial sizing wax for the lube, which is removed prior to loading. Is any material removed from the inside of the necks during turning?

I think the wobble is just a distraction unless your death griping the turner, and it doesn't look like you are. Measuring the mandrels might provide some information, but different brass will spring back differently. If you have access to a set of pin gauges, you could measure the expanded necks themselves.

Reloading rites of passage are best performed on cheap brass.
 
#25
Stangs55 said:
Noooooo....don't tell me that :( I'm afraid that I'm steadily arriving at the same conclusion. The K&M may work...but where is the consistency? And how much of this do I really have to go through for each piece of brass? I don't mind something taking time to do right...but I do mind it if it's not the same between cases...

I headed over the 21st Century to see what it would cost to get a rig for turning my 300 WSM, 308, and 300 RUM.... The total comes to $400.36... Ouch. There's a spot for a coupon....anyone know of any in case I decide to go this route? I wonder if K&M will return the turner since it's only a week old...
Click to expand...

Sorry to be the bearer of bad news. I'm not knocking the K&M, just saying I couldn't get it to work the way I wanted. My technique may have been off as well.

It is a pain to set & reset them for different calibers/neck lengths. I decided to relegate the K&M for hand skimming .223 cases for my JP (since I don't do that many), and have the 21st Century set up for my .308. So much better when you can just set & forget it. Good luck...
 
#27
i am doing something very similar. Same caliber, brass, same k&m tools, same process with some differences. When i start setting up my turning, i use the k&m hand tool instead of the drill. i verify that the results are consistent. slow and tedious but its just me slowly turning the casing on the carbide mandrel. i do use the graphite instead of lube. Once i am satisfied with the results (i shoot for .0145 neck thickness with lapua 308. i then mount the unit in a cordless drill which wobble just like yours. However, i run the unit slow and take my time. at least with my setup for 308 the case of the mandrel is pretty tight and will heat up, so i run slow.

i use the same setup for rem 260 and have similar results. i start with the hand setup to verify results and then mount to cordless to turn slow. you vids spin the drill much faster than i ever have.

i am currently concentrating on neck tension,stainless steel clean, aneal, body size, trim, turn neck if necessary champfer, neck only size and load and it has improved my consistency.
 
#28
Stangs55 said:
Alright....I'm videoed out....final video using brand new brass and the drill in a vice...

Neck Turning Brass Part 3 - YouTube
Click to expand...

Please take following with a grain of salt. Not really sure if any thoughts below mean anything but I am simply throwing thoughts your way. I am far from an expert in neck turning but I do appear to obtain very consistent necks after turning so this is ONLY reason why I am comparing your technique to mine.

As I watch this video following thoughts come to my head:
1. [Video time 2:34] I, by hand, carefully tighten brass into case holder to make sure of a good fit. Maybe using drill power to tighten brass into case holder is throwing case off every so slightly.
2. [Video time: 3:00] Clearance between neck and pilot appears to be (not a lot but) a lot more lose than what I experience. My clearance is definitely more snug than this video. I almost have to slowly turn my drill in order to slide pilot into/down neck.
3. [Video time: 4:13] FWIW: Your very last pass is just a bit faster than ALL my passes - start to finish)
4. [Video time: 4:24] I do not use drill to do any further work. I remove case by hand and not use drill power. I like to FEEL every bit as possible as this may allow me to feel something that does NOT feel good. Where drill power would not allow me to feel something incorrect.

As someone else mentioned, what is neck outcome when you do NOT use drill at all? This should rule in or out drill as issue. .

Just throwing a few more thoughts your way.
 
#29
Just some thoughts when dealing with this close of a tolerance. Temperature is very important. Make sure everything has temperature stabilized. I leave my brass in the garage for two hours before using the expanding mandrel, (press and dies are in the garage). I then let my tools and brass temp stabilize again when I bring them into the room where I sit in front of the tube. When using power to turn I use a cordless screwdriver. Shop Skil 4-Volt Max 1/4-in Cordless Screwdriver at Lowes.com . It took me a bit before I learning a good feed rate to minimize heat build up and cutter deflection from going too fast or taking too heavy a cut. I recommend doing some by hand till you get consistent results. Using the power tools will mask the "feel" of the cutter heating up from too high a feed rate.

The wobble in your vids is not because of the tool but because there is no way to positively center the case in the shell holder in relationship to the center turning axis. It's unavoidable and not a problem as long as the case to mandrel fit is proper.

David
 
#30
adsc10 said:
Just a thought, have you checked the mic. to be accurate and consistent?
Click to expand...

It's brand new and has been very accurate and consistent in the capacity I've tested it...

tolnep said:
i am doing something very similar. Same caliber, brass, same k&m tools, same process with some differences. When i start setting up my turning, i use the k&m hand tool instead of the drill. i verify that the results are consistent. slow and tedious but its just me slowly turning the casing on the carbide mandrel. i do use the graphite instead of lube. Once i am satisfied with the results (i shoot for .0145 neck thickness with lapua 308. i then mount the unit in a cordless drill which wobble just like yours. However, i run the unit slow and take my time. at least with my setup for 308 the case of the mandrel is pretty tight and will heat up, so i run slow.

i use the same setup for rem 260 and have similar results. i start with the hand setup to verify results and then mount to cordless to turn slow. you vids spin the drill much faster than i ever have.

i am currently concentrating on neck tension,stainless steel clean, aneal, body size, trim, turn neck if necessary champfer, neck only size and load and it has improved my consistency.
Click to expand...

The second video turns the brass pretty freaking slow...you're going slower than this?

OF&B said:
It looks to me like there is too much clearance between the case necks and mandrel. I can't get brass over the turning mandrel unless it's lubricated and turning. If the bit was moving, it'd only move out.

I also only turn for 60-80% cleanup and wind up with less than 0.000 5" variance if I discard anything that doesn't get turned that much. The turned part varies less than half that. I'm using an older Sinclair turning setup and a case holding setup like yours. I do 223 directly in the drill chuck. I still have .0015 - .002" neck tension after turning. I use Imperial sizing wax for the lube, which is removed prior to loading. Is any material removed from the inside of the necks during turning?

I think the wobble is just a distraction unless your death griping the turner, and it doesn't look like you are. Measuring the mandrels might provide some information, but different brass will spring back differently. If you have access to a set of pin gauges, you could measure the expanded necks themselves.

Reloading rites of passage are best performed on cheap brass.
Click to expand...
Tristian19 said:
Please take following with a grain of salt. Not really sure if any thoughts below mean anything but I am simply throwing thoughts your way. I am far from an expert in neck turning but I do appear to obtain very consistent necks after turning so this is ONLY reason why I am comparing your technique to mine.

As I watch this video following thoughts come to my head:
1. [Video time 2:34] I, by hand, carefully tighten brass into case holder to make sure of a good fit. Maybe using drill power to tighten brass into case holder is throwing case off every so slightly.
2. [Video time: 3:00] Clearance between neck and pilot appears to be (not a lot but) a lot more lose than what I experience. My clearance is definitely more snug than this video. I almost have to slowly turn my drill in order to slide pilot into/down neck.
3. [Video time: 4:13] FWIW: Your very last pass is just a bit faster than ALL my passes - start to finish)
4. [Video time: 4:24] I do not use drill to do any further work. I remove case by hand and not use drill power. I like to FEEL every bit as possible as this may allow me to feel something that does NOT feel good. Where drill power would not allow me to feel something incorrect.

As someone else mentioned, what is neck outcome when you do NOT use drill at all? This should rule in or out drill as issue. .

Just throwing a few more thoughts your way.
Click to expand...

Thanks again for the input...really, really appreciate it :)

1. Possibly...but the problem with a looser fit is that the brass can come loose when turning

2. As in the above post too...I kinda agree. If I expand, the brass easily slides onto the carbide pilot. People mention it getting hot when they turn with a drill? Um...no...I can spin at lightspeed and it won't heat up...I just assumed this was a result of the carbide, but maybe not.
Unfortunately, my outside micrometer is in the mail headed this way....so I've only got some digital calipers to measure, but this is what I'm getting for the 30 cal pilot and mandrel:
Expander: .3095
Pilot: .3075
So bascially there is 0.002 clearance.
I'm curious how this compares to others...Anyone care to bust out their pilot, expander and micrometer? :)

3. Thanks

4. Unfortunately, I didn't buy the handle for the driver...I only purchased the drill adapter, so I have nothing to attach this to for hand turning. Of course I did that because I have zero desire to hand turn all the brass I go though... I "need" to find a power solution...
 
#31
Stangs55 said:
Unfortunately, my outside micrometer is in the mail headed this way....
Click to expand...

I for one am curious to know the interior size of neck area BEFORE and AFTER you FLS and, as well, AFTER you run expander through neck. Truth is, I cannot see how any of my previous thoughts would help with your results but I wanted to share with you just in case they may have sparked a thought on your end.

My earlier question regarding which were carbide and not carbide was really to make make sure I was on same page with you. I myself have yet to see a carbide expander. Not to say they do not exist.

As for brass lot question, I asked because my custom gun builder had purchased 300 cases of Lapua brass some years back. I recall him telling me after he turned ALL 300 necks there turned out to be an issue with this lot and he threw ALL 300 in garbage. Not to say there is anything worng with your brass BUT just had to ask.
 
#32
308 bullet - 0.308 1
Sinclair Expander - 0.306 5
Well Used Sinclair Turning Mandrel - .305 2
A .305 pin gauge is snug in the brass, .306 no chance
The brass came out of a Dillon trim die taking a .301 pin gauge

My 223 setup gives similar undersizes. Both setups are at least 15 years old and have a couple thousand rounds turned at least, so the turning mandrels have some wear. I use the expanders a lot after the Dillon trim die too for brass I don't turn, so these are probably not what you get out of the package.

Quarter thou tops for the total variation in the cutting. I try to cut enough that a half thou is the total variation in the neck thickness. If they don't cut enough, I throw them in a separate pile and measure them when I'm done. In most cases, those are the good ones. Very uniform, just under the cutting thickness, and just over my minimum.

The difference in diameters isn't going to be the clearance because the brass will spring back some. The clearance should be less. How much less depends on how small it was expanded up from, how hard the brass is, and what the starting neck thickness is.
 
#34
Tristian19 said:
I for one am curious to know the interior size of neck area BEFORE and AFTER you FLS and, as well, AFTER you run expander through neck. Truth is, I cannot see how any of my previous thoughts would help with your results but I wanted to share with you just in case they may have sparked a thought on your end.

My earlier question regarding which were carbide and not carbide was really to make make sure I was on same page with you. I myself have yet to see a carbide expander. Not to say they do not exist.

As for brass lot question, I asked because my custom gun builder had purchased 300 cases of Lapua brass some years back. I recall him telling me after he turned ALL 300 necks there turned out to be an issue with this lot and he threw ALL 300 in garbage. Not to say there is anything worng with your brass BUT just had to ask.
Click to expand...

OF&B said:
308 bullet - 0.308 1
Sinclair Expander - 0.306 5
Well Used Sinclair Turning Mandrel - .305 2
A .305 pin gauge is snug in the brass, .306 no chance
The brass came out of a Dillon trim die taking a .301 pin gauge

My 223 setup gives similar undersizes. Both setups are at least 15 years old and have a couple thousand rounds turned at least, so the turning mandrels have some wear. I use the expanders a lot after the Dillon trim die too for brass I don't turn, so these are probably not what you get out of the package.

Quarter thou tops for the total variation in the cutting. I try to cut enough that a half thou is the total variation in the neck thickness. If they don't cut enough, I throw them in a separate pile and measure them when I'm done. In most cases, those are the good ones. Very uniform, just under the cutting thickness, and just over my minimum.

The difference in diameters isn't going to be the clearance because the brass will spring back some. The clearance should be less. How much less depends on how small it was expanded up from, how hard the brass is, and what the starting neck thickness is.
Click to expand...

Tristian19 said:
Measurements:
Sinclair .308 Expander: .307
Sinclair .308 Neck Mandrel .306

Do you have an answer to your issue?
Click to expand...

Unfortunately...I don't have pins to measure my inside diameter...

So judging by those two measurements....it would seem that I may have too much clearance? I'm curious what other K&M users see on the pilot and expander...? My outside micrometer will be here Thursday...so I'll have a precise measurement then...

So here's where I'm at...

- I emailed K&M on Sunday and pointed them to this thread. No word back from them yet...

- I keep wondering if measuring error is a part of it....so if you see that I'm doing anything wrong in these videos when measuring, then please let me know! You can see how I'm doing it! The micrometer has a ratchet stop...and I only go one click in...so I don't think I'm over doing it. Now...this is the Mitutoyo micrometer with the standard head and not the one with the 60 degree modification... not sure if that really makes a difference...

- As such...I'm strongly considering purchasing the Redding Case Neck Gauge. I was thinking it would be more to sort brass...but would this really work well enough as the only measuring tool to setup my neck turner? It says it's accurate to 0.001" and it'll always measure in the same spot...it would also seem take away any variable I may introduce in my measuring process... Is it enough? Or do you really need a precision micrometer to accurately setup a neck turner?

Thanks again for all the thoughts and feedback!
 
#35
How did you FL resize? What die was used and did it have an expander ball?

What was the neck OD after resizing, and then after it was run over the expanding mandrel? Calipers are good enough for this.

I'd buy a bag of cheap range brass locally or on GB to experiment on before I bought anymore toys. Your micrometer technique looks practiced and you can read that vernier a lot faster than my old eyes can. I'm a little surprised about how much variation in neck thickness your batch of Lapua brass has. I've assumed we were discussing thickness variation from side to side, are we really talking about front to back?
 
#38
[video=youtube;zj-UZgqfCjg]https://www.youtube.com/watch?v=zj-UZgqfCjg[/video]
2606-7-2013.jpg


I used the Bryant method to turn the necks of Lapua 308 Palma brass down before necking it down to 260.
I made neck dies, and the final neck die was a Lee 260 Collet neck die.
I built this rifle and took it to the range 3 years ago with 2 other rifles, but wound up hunting with one of the other rifles.

But I have the brass I turned and some I fired.
With the ball micrometer it measures .0050" runout.
With the dial calipers it measures .0001" [I am the master of reading between the hash marks on the dial].
The lumps in the neck from the collet neck die are screwing up the ball mike.

So I took out a piece of dirty fired brass, as that should have flattened out the lumps.
It measures 0.0003" runout with the ball mike.

I don't know it this helps, hope it did.
 
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