I'm getting ready to starting mandrel expanding my case necks and am trying to decide what size to go with. It will be a Sinclair mandrel and I will be using it on a .260 rem I use for PRS style matches and long distance hunting. Sinclair offers their mandrels in .001 or .002 under for neck tension. I was told for match ammo I should go with the .002 under. What say you hide?
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Which mandrel size should I go with?
- Thread starter david8989
- Start date
If you can afford it, order the 21st century full 6.5mm set. They come in .0005 increments. Then you can experiment with different tensions.
DT, how are you going to know what the correct tension is? Group size on paper... 5 rounds per mandrel... would you do this after determining your jump? Or, could you measure seating force (21st Century hydraulic measure)? Appreciate the feedback. Thanks!
All of the above. The tricky part is neck tension and seating pressure are not always the same. Friction plays a big part in seating pressure.
I like to keep my seating pressure on my hydro press in the 30psi range.
On new brass, I typically need to run a larger (and sometimes oversized) mandrel to get that seating pressure as the necks are completely clean.
After brass has been fired and has carbon, I’ll end up using a .003 under bushing and a .001, .0015 or .002 under mandrel to achieve that pressure.
After first firing, I’ll start playing with tension/pressure after I’ve found the seating depth. Then go with whatever bushing/mandrel achieve the best results without using too much seating pressure.
Also, with new brass, I err on the low side.
For example, I just loading virgin .22br. With a .224 mandrel I was in the 80+ psi range. With a .2245 mandrel I was in the 10psi range.
To get in the 30-40 psi range, I’d need to either use dry lube, polish, or spray lube. Didn’t feel like the hassle.
I’m using the 10psi for first firing and then will revisit tension/pressure on 2nd firing.
For example, I just loading virgin .22br. With a .224 mandrel I was in the 80+ psi range. With a .2245 mandrel I was in the 10psi range.
To get in the 30-40 psi range, I’d need to either use dry lube, polish, or spray lube. Didn’t feel like the hassle.
I’m using the 10psi for first firing and then will revisit tension/pressure on 2nd firing.
DT, I’d like to follow up. Disclaimer, I haven’t loaded a single piece of brass yet - but I have my equipment... so can we discuss hypotheticals? I have 800 pieces of Lapua brass LFP, once fired. My process on paper is to: 1) use a Forster Coax and Lee depriming die; 2) clean (SS pins/wet & dry in a dehydrator); 3) anneal (Amp); 4) lube; 5) Redding S FL resizing die - no expander ball... .336 bushing (OD is .338 on my 308)... but I also have a .335 to test... then 6) Sinclair mandrel... 30 cal expander mandrel was purchased in error, so now I purchased a “turning” mandrel.... “question”... for once fired brass is this necessary?
I had thought so... constrict down with bushing, then expand out to “consistent” ID with a mandrel... BUT my mate (CDN F Class team shooter) skips the mandrel on once fired.... only used with new brass. His process goes form FL resizing/bushing to seating... do I need to expand out with a mandrel?
To finish... 7) 2nd cleaning to get rid of the lube.... 8) trim to length; 9) note.... take a 308 nylon brush and a drill to clean/polish inside the necks (3 passes)... did you see that thread with annealing oxide... this removes it...I had thought about using dry carbon lube (it’s on my bench), but it’s suggested that it’s not required...9) seating... wilson,Sinclair die - target “30”.
Sorry for the long story... but I wanted to vette my approach since the seating die (with constant OD of the Berger 168 Hybrid Target bullets) should give the best indication of “neck tension”.
Thoughts on initial pressure (friction) and steady pressure (seating)... I plan to reduce the initial spike by removing the oxide... but perhaps a light dusting of carbon might also be required... thoughts?
To the OP... thanks for bring this question up... just a few more questions on my part.
I had thought so... constrict down with bushing, then expand out to “consistent” ID with a mandrel... BUT my mate (CDN F Class team shooter) skips the mandrel on once fired.... only used with new brass. His process goes form FL resizing/bushing to seating... do I need to expand out with a mandrel?
To finish... 7) 2nd cleaning to get rid of the lube.... 8) trim to length; 9) note.... take a 308 nylon brush and a drill to clean/polish inside the necks (3 passes)... did you see that thread with annealing oxide... this removes it...I had thought about using dry carbon lube (it’s on my bench), but it’s suggested that it’s not required...9) seating... wilson,Sinclair die - target “30”.
Sorry for the long story... but I wanted to vette my approach since the seating die (with constant OD of the Berger 168 Hybrid Target bullets) should give the best indication of “neck tension”.
Thoughts on initial pressure (friction) and steady pressure (seating)... I plan to reduce the initial spike by removing the oxide... but perhaps a light dusting of carbon might also be required... thoughts?
To the OP... thanks for bring this question up... just a few more questions on my part.
You can skip the mandrel and set the neck tension with a bushing (I Use .002 under). I did that for a while on a 6.5 gasser. But the necks need to be ding dent free and high quality brass. Worked pretty good.
I now use a Bushing and mandrel method you describe. However I do all my brass prep on a Dillon 550. The mandrel helps me with concentricity, and makes sure the interior necks are uniform and round. (Shooting PRS sometimes the brass gets abused)
I now use a Bushing and mandrel method you describe. However I do all my brass prep on a Dillon 550. The mandrel helps me with concentricity, and makes sure the interior necks are uniform and round. (Shooting PRS sometimes the brass gets abused)
I anneal before I do anything. That what I’m cleaning after the annealing. Sometimes the residue left from annealing causes issues. So I annealer first so I don’t have to add additional cleaning steps.
I also have stopped using the SS pins and just wet tumble with soap. The only reason we clean is to make sure nothing will mess up our dies and chamber. Anything beyond that is purely aesthetic. The pins don’t really do anything except make brass shiny.
I expand out with a mandrel at all times for the sake of consistency.
I also have stopped using the SS pins and just wet tumble with soap. The only reason we clean is to make sure nothing will mess up our dies and chamber. Anything beyond that is purely aesthetic. The pins don’t really do anything except make brass shiny.
I expand out with a mandrel at all times for the sake of consistency.
DT/HDD... sounds safe to place the mandrel in the mix... concentricity insurance... if I’m shooting .308, then my turning mandrel at .306 should be a good start right?
ps...There was an earlier discussion that case mouths were being peened by wet tumbling due to brass interaction… One solution proposed was to increase the weight of the stainless steel media... DT when you only use a solution, without SS media, do you notice case mouth peening?
ps...There was an earlier discussion that case mouths were being peened by wet tumbling due to brass interaction… One solution proposed was to increase the weight of the stainless steel media... DT when you only use a solution, without SS media, do you notice case mouth peening?
I've been using a Forster FL sizing die honed for .004 under loaded diameter... using a bushing die that does this is fine as well. I then use 21st Century TiN turning mandrels with give .002 neck tension.
Tumble in corn cob (stopped SS cleaning a long time ago it does nothing for you down range and is a lot of work) anneal every 3rd firing, run through FL honed die when bumping shoulders or Redding bushing when not bumping shoulders, then into mandrel to set .002 final neck tension.
Been doing this for many years with virtually no runout, single digit SD's and excellent accuracy.
I've tested all the different mandrels, all the different cleaning methods, annealing every time vs 3 and 5x. I can tell you the target down range doesn't care...
Tumble in corn cob (stopped SS cleaning a long time ago it does nothing for you down range and is a lot of work) anneal every 3rd firing, run through FL honed die when bumping shoulders or Redding bushing when not bumping shoulders, then into mandrel to set .002 final neck tension.
Been doing this for many years with virtually no runout, single digit SD's and excellent accuracy.
I've tested all the different mandrels, all the different cleaning methods, annealing every time vs 3 and 5x. I can tell you the target down range doesn't care...
I haven’t yet. But I’m only running them about 30min - 1hr prior time sizing. Then sometimes another 30min to get wax off.
Ask 10 people and you’ll get 10 answers. Some say it’s the brass peening itself and others say it’s the media.
Half the time, if it’s not a lot of brass, I’ll just wipe it down with a cloth. I only care about the functionality purposes of cleaning. I don’t care about shiny brass.
So you are obviously way further down this rabbit hole than I currently have the time or funds for, lol. My overall goal was to go from a full length sizer with expander button to a FL sizer with no button followed with a -.002 mandrel to get better results in case neck runout and more consistent neck tension. So my simple question posed to you is if you could only choose a single sized mandrel for a .264 application what would it be.
.002 is going to be your preferred default.
You dont want to use a FL sizer with a button. Use a FL sizing die with no button, or a FL bushing die with no button when using mandrels. The reason most of us use honed FL sizing dies or FL bushing dies with a bushing that sizes that neck .004 under loaded neck diameter is so we arent overworking that brass which extends brass life. If you squeeze it down .004 under loaded neck diameter with the FL or bushing die, then you rmandrel only has to open that neck up .002 to give you your final neck diameter which leaves you with .002 neck tension when your bullet is seated. This is the ideal sweet spot after lots and lots of testing.
You only need 1 mandrel for each caliber and that one mandrel is the 21st Century TiN coated "TURNING" mandrel. This mandrel will leave you with .002 neck tension every time. If you buy the "Expander" mandrel that will leave you with .001 neck tension..
Here you go, you will see on the right side column those are the TiN coated mandrels that need no lube. Get one for each caliber you want to size and be done.
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Yes the turning mandrel is the one I use for setting neck tension (-.002 from caliber) I am using the Sinclair carbide mandrel. It works well for high volume use and seems to hold up better if the lubrication if less than Optimum. I have the 21st century TiN that I use for my 30-06 (.306) hunting loads and it is showing signs it requires more generous inside neck lube. It works great just an observation.
I also agree with some others in regards to ss tumbling the juice isn’t worth the squeeze. I use corn cob media. I like the carbon in the neck. It seems to give a more consistent release. I anneal every 2-3 firings.
Really interesting and first Ive heard of this. This 21st Century TiN turning mandrel has over 50K+ on it. Probably closer to 75k no lube. Just whatever gets in the necks when spraying with linolin before running on my 223 processing toolhead on my XL650. Looks good as new and works flawless. I use it on my Lapua 223 brass on my 550 when sizing brass for my bolt guns as well. No lube.
I had that happen before. I'm 99% positive that's not wear in the TiN. That's brass on the mandrel. That should buff off. I had to do that once
This is exactly the info I needed. Thank you. I agree with you entirely on getting away from the button and going to the mandrel, finally seeing the error in my ways, lol.You dont want to use a FL sizer with a button. Use a FL sizing die with no button, or a FL bushing die with no button when using mandrels. The reason most of us use honed FL sizing dies or FL bushing dies with a bushing that sizes that neck .004 under loaded neck diameter is so we arent overworking that brass which extends brass life. If you squeeze it down .004 under loaded neck diameter with the FL or bushing die, then you rmandrel only has to open that neck up .002 to give you your final neck diameter which leaves you with .002 neck tension when your bullet is seated. This is the ideal sweet spot after lots and lots of testing.
You only need 1 mandrel for each caliber and that one mandrel is the 21st Century TiN coated "TURNING" mandrel. This mandrel will leave you with .002 neck tension every time. If you buy the "Expander" mandrel that will leave you with .001 neck tension..
Here you go, you will see on the right side column those are the TiN coated mandrels that need no lube. Get one for each caliber you want to size and be done.
Arbors and Mandrels
21st Century Shooting, Reloading products, Reload, reloading ammo, 21st century, twenty first century shooting, shooting, gun arbors, mandrels, reloading, tools for reloading, front rest, f class, bench rest, short handle, arbor press, powder measure, bullet, bullet comparators, die base, shell...www.xxicsi.com
