Sizing Mandrels vs FL sizing die with expander ball??

I'll take it one step further. For prepping new brass, I neck size with a .308" bushing neck sizer, run my .282" expander mandrel for .280 AI, run a .282" inside neck reamer, then turn the OD of the necks just enough until there are no untouched spots. Downside, it requires me to have multiple neck bushing sizes. Is it necessary? Not at all, but I'm OCD like that. It's turned out that my Nosler .280 AI brass ends up with a .309" OD after turning. To which I use a .308" bushing for .003" neck tension.
 
KurtisB said:
I'll take it one step further. For prepping new brass, I neck size with a .308" bushing neck sizer, run my .282" expander mandrel for .280 AI, run a .282" inside neck reamer, then turn the OD of the necks just enough until there are no untouched spots. Downside, it requires me to have multiple neck bushing sizes. Is it necessary? Not at all, but I'm OCD like that. It's turned out that my Nosler .280 AI brass ends up with a .309" OD after turning. To which I use a .308" bushing for .003" neck tension.
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I skip all the bushing die stuff and bring the ID to target with the mandrel. I know my 7mm FL die with no expander sizes necks to .270 ID. Some question whether this works the brass too much, and my answer is, no, because I anneal and I've never had a split neck before tossing brass for enlarged primer pockets.
 
So maybe I’m being enlightened here. I use the Lee Collet Necksizing die, which does use a mandrel, and it’ll also decap. The standard mandrel is I believe 2 thousandths under caliber diameter, and Lee offers undersized mandrels that are an additional 2 thousandths undersized for about $4 or so per mandrel. So for my 708, the included mandrel measures .282, and the undersized mandrel measures .280. I’ve been running the .280 mandrel for loading Hammers, and the larger mandrel would be used for load C&C. Since these mandrels are set to decap, they wouldn’t remove burrs and what not I’m guessing. Guess you could always square cut the mandrel so that it would remove burrs and donuts. 21st Century is no doubt better, but at multiple times the price I’d assume. I use either a Redding body die or an FL die with the expander removed for my FL sizing.
 
Schmo said:
So maybe I’m being enlightened here. I use the Lee Collet Necksizing die, which does use a mandrel, and it’ll also decap. The standard mandrel is I believe 2 thousandths under caliber diameter, and Lee offers undersized mandrels that are an additional 2 thousandths undersized for about $4 or so per mandrel. So for my 708, the included mandrel measures .282, and the undersized mandrel measures .280. I’ve been running the .280 mandrel for loading Hammers, and the larger mandrel would be used for load C&C. Since these mandrels are set to decap, they wouldn’t remove burrs and what not I’m guessing. Guess you could always square cut the mandrel so that it would remove burrs and donuts. 21st Century is no doubt better, but at multiple times the price I’d assume. I use either a Redding body die or an FL die with the expander removed for my FL sizing.
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Totally different mandrel use comparing Lee neck sizing die with 21st Century mandrels. The Lee die is pressing a larger than caliber diameter brass neck into the mandrel, whereas the 21st Century type expand the brass to diameter with greater force which in the process is smoothing things out.

I stopped using Lee collet dies some 15yrs ago when I came upon the FL sizing with .002-003 shoulder bump. Also, I remember the standard collets gave some very light neck tension, like .001-.0015. I would reduce the diameter of the collets with emery cloth to get more neck tension. (As per Lee's instructions included with the dies)
 
jrebel said:
I need to buy that guy a cigar!!!!! BFD, my wife hates you, but I could care less!!!!! I like you and that’s all that matters. Keep spending my money!!
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21stcenturyinnovation.com

21st Century Innovation

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I run both short and long cartridges through the short/short action die with the respective caliber mandrels. Whatever you do, don't look at their hand primer. It's the best most terrible :ROFLMAO: I've tried and it has click adjustable seating depth...
 
How do you know what size mandrels to buy? If I bought the kits from 21st century for every caliber I have that would be over $1100, damn those are expensive!
 
Indeed they are expensive. As Brad suggested earlier, decide roughly which neck tension you’d like and factor in .0010-.0015”-ish spring back.
Eg, yesterday I ran the .3075” mandrel through some brass and got an ID of .306” for .002” neck tension.

If you spring for the block that organizes them, you’ll be very pleased once the sticker shock wears off. Their products are very nice!

IMG_4012.jpeg

Fwiw, I eschewed the advice to get the hand primer from 21st Century and instead upgraded the RCBS (which was an upgrade from the Lee…ha!) with the Frankford Arsenal primer. It also allows one to adjust seating depth, and it has a primer tray for lazy folks like myself.

Edit to add, in the picture above, I have more than enough mandrels to get proper neck tension on 7mm and 30 cal cartridges.
I also have a few to round case mouths for future 22 and 264 projects. In other words, it is not necessary to buy the entire kit.
 
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aratliff said:
Indeed they are expensive. As Brad suggested earlier, decide roughly which neck tension you’d like and factor in .0010-.0015”-ish spring back.
Eg, yesterday I ran the .3075” mandrel through some brass and got an ID of .306” for .002” neck tension.
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I've seen spring back of up to .003 on thicker Lapua brass made thicker by sizing down 308 brass to 708 brass, and then .0005 on virgin Peterson brass. So, a bit of experimentation is needed starting out with brass and then that needs to be recorded like all the other stuff we record on the recipe list. I have a line item for "mandrel".

Thicker the brass & more it is stretched to diameter = more spring back.
Neck turn same thick brass and less spring back.
 
aratliff said:
@BFD got me using mandrels.
To answer @Edd, I can think of a couple reasons with a tired mind.
1) they allow one to sharp shoot neck tension. The 21st Century mandrels I use are offered in half thousandth diameters.
2) for new brass with dented necks, you can make the necks round without running through a die and unnecessarily working the brass.

@jrebel, I don’t have enough experience to answer your question with any degree of certainty, but I would think they would add to consistency. 🤷🏽‍♂️

My next FAFO project will be to try a FL bushing die.
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I recently started using an FL bushing die. I took out the expander ball. Seems to work pretty good so far. Bought a neck tension gauge to verify.
 
I've just started annealing (torch + deep socket) and mandrel neck expanding (21st Cent.). I loaded a few 280AI and could feel the improved consistency when seating the bullets even with the RCBS rock chucker press. My Redding sizer die was easy as I just removed the expander ball sleeve. My RCBS sizer dies have the expander built in as part of the decapping pin holder so I'm going to try substituting one from a smaller caliber or modify an extra to a smaller diameter so as to make sure there is no expanding.

For my first go I am trying mandrels that are .0025" smaller than bullet diameter.
 
fuzzymarindave said:
I've just started annealing (torch + deep socket) and mandrel neck expanding (21st Cent.). I loaded a few 280AI and could feel the improved consistency when seating the bullets even with the RCBS rock chucker press. My Redding sizer die was easy as I just removed the expander ball sleeve. My RCBS sizer dies have the expander built in as part of the decapping pin holder so I'm going to try substituting one from a smaller caliber or modify an extra to a smaller diameter so as to make sure there is no expanding.

For my first go I am trying mandrels that are .0025" smaller than bullet diameter.
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Love me some drill/torch/socket annealing! Small batches, like 100 or so. MAP/PRO gas, yellow bottle, gets it done. I'm totally scientific about it too. I let them spin till the anneal line forms just under the shoulder and call it good! :cool:

Large batches get the mesmerizing Ugly Annealer. I shut off the shop lights, turn on the machine, and gaze upon the operation of the mad scientist looking deal! You all can laugh, but don't knock it till you try it, and @JesseJ, the operation can be fully gazed upon form the pontification area...
 
Well.....the mandrels are inbound. Bought mandrels for my 6.5's along with the mandrel die, billet aluminum holder as seen above in aratliff's post. Also bought some case mouth dry lube from the same 21stcentry company. If I like them, I will be buying 30, 7mm, 338 and .223.

Just out of curiosity.....what does everyone shoot for with neck tension. All my ball expanders give me between 2-4 thousandths. Anecdotally, it appears 2 thousands seems to be the sweet spot. Our 300 wsm's expander ball gives us 2 thousands and they are my best shoot rifles with lowest ES and SD's.

I was danger close to buying their new arbor press and the hydro bullet seater with gauge. Figured that would for sure land me in the doghouse so I deleted them from the list. Man this 21'st century site is as bad as any reloading site I have ever seen. It's like taking a recovering alcoholic to the bar.......except I'm not recovering from my reloading addiction. 🤣 🤣
 
BFD said:
the mesmerizing Ugly Annealer. I shut off the shop lights, turn on the machine, and gaze upon the operation of the mad scientist looking deal!
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You and me both. The idea of an annealer is better annealing, and the offloading of a task and time saving. I get the first two benefits. I don’t get time saving because I too turn off the lights, sit back, and watch the brass glow, and then drop into the pan. Basically the same thing as staring into a fire for hours.
 
BFD said:
21stcenturyinnovation.com

21st Century Innovation

21stcenturyinnovation.com 21stcenturyinnovation.com

I run both short and long cartridges through the short/short action die with the respective caliber mandrels. Whatever you do, don't look at their hand primer. It's the best most terrible :ROFLMAO: I've tried and it has click adjustable seating depth...
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Got a mandrel coming for my .308. Thoughts on the moly lube they recommend. I have graphite and beads will that suffice with hunting loads? The mandrel and holder already take a big bite out of the budget 😁
 
Nicoli7153 said:
Got a mandrel coming for my .308. Thoughts on the moly lube they recommend. I have graphite and beads will that suffice with hunting loads? The mandrel and holder already take a big bite out of the budget 😁
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I use Hornady One Shot for sizing and make sure to have the inside necks lubed. Then I add a little Hornady Imperial Size lube on the mandrels. I swab the inside of the necks with acetone before bullet seating. But yeah, graphite is fine, you can buy a big bag from Amazon $16 probably last a lifetime. I use the graphite to coat the bore after cleaning mainly. I don't use graphite for handloading for fear it will always be all over the place mess.
 
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