21st Century Expander Mandrels - Setting consistent Neck Tension

[@user-un5my5bw4j]

I am a 1000yd benchrest competition shooter in both light gun and unlimited gun classes. You did this pretty good. I watch you because you have gotten your information out of books written by known, competent shooters just like i have over the years rather than from self proclaimed long range shooters on forums and youtube. Ofcourse i even see well known f class and prs shooters make wrong claims on the subject but I think you do pretty well and appreciate the common sense approach.

[@patricks792]

I have recently decided to get back into reloading and have been watching a lot of your videos. I can't tell you how helpful they have all been. Thank you so very much for taking the time to make them and share your extensive knowledge with the rest of us. All your time and efforts are greatly appreciated.

[@sloboatazmesa309]

On your, and Cortina's, recommendation, I bought a 21st C die and .224 mandrel. I also bought a few gauge pins to check them with. Well, well...fl sized a couple of misc brass with my Forster die machined for .002 tension, no go with a .222 pin, ran the mandrel thu and a .222 pin 'just' slides in. A .2225 pin is a no go. Same for new, untouched, Lapua$$$!!! brass. No go for the .222 before mandrel, go for .222 after, and no go for .2225. Seems the mandrel is doing it's job. I thought there would be more spring back. I'll check those four cases again tomorrow. Some chrono time this weekend will tell the tale! I've perused some of your other vids also. While you are dealing with a 'significantly' higher budget than I, lots of good content, well presented. Thanks

[@mvic61191]

I’ve been using their mandrel/mandrel die. Their customer service is absolutely amazing. Pete returns emails very quickly and if there any issues they are very quick to assist. I have not dealt with Sinclair in the same way so I can’t speak for them. However if you were on the fence go with 21ST century, I love being able to speak with someone should I have any issues.

[@blkmoon33]

21st century mandrels are the best I've ever used. In my Rem 660 in 243 the neck tension works best at 1.5 thou. In my 223 2 thou seems to work best. I do turn the neck down on both. Very informative video thanks. 21st does make carbide mandels now.

[@MrRanggong]

Thanks for taking the time to post these videos and for being humble enough to point us to resources so we can expand our knowledge. Top Grade Ammo is an excellent book . Zediker was a guy that seemed obsessed with minutia but he had the trophies to prove his reasoning was valid. You seem to be the same type of guy AND you post interesting videos!

[@BoltActionReloading]

Thank you Sir. We are all learning is the way I see it.

[@timmartin6410]

Very interesting video. I've just recently started using a expander mandrel at .002 under bullet diameter. Haven't been to the range yet to test, but the one thing I've noticed is more consistent bullet seating pressure, each feels pretty much like the last. When using Type-S busing die alone, some felt more resistance to seat than others, no consistency. Can't wait to see if it makes a difference in my groups.

[@qedsteve]

After watching, I've gone and ordered the 21st Century 6.5 set. I currently have the Redding S bushing die set but have found that there is still some uncertainty on neck tension. I'm too lazy to neck turn (though I can if needed). I think that if I use the expander mandrels, I'll be making the best choice for consistent neck tension. If I start to see differences in measured case mouth OD after mandrel sizing, then I'll start neck turning again but think the use of the case mouth sizing mandrels is going to eliminate a LOT of uncertainty! Good info.

[@bryanmarks4070]

Scott Satterly was talking about this in the reloading podcast on the “modern day sniper” podcast” episode #14 you should really listen!! to it. I switched my reloading technique after that podcast. I use just a regular Hornady FL sizing die with out the expander stem and then run them thru expander mandrel. He was saying if you using a bushing die it leaves a small part on the base of your neck that doesn’t get sized which can for a carbon ring in your chamber. My reloads are better in every way after I started doing this.

[@RetrieverTrainingAlone]

Great tip on the podcast! I've been doing the same...remove the decapper/expander ball stem from full length die and use the Lee Universal Decapper to remove primers, full length resize with no expander ball, then use expander mandrel for inside neck diameter prior to turning necks for outside diameter.

[@o2wow]

After getting the same die/mandrel set I discovered there was a wide variance in the effort needed to expand cases. This was in a lot of several hundred 6.5 Grendel cases that had been fun length sized with a carbide expander ball, however some necks were so tight they were shaving the bullets as they were seated. These cases were not precision reloads. They were mostly fired in an AR and had one to three reloads. They could stand to be annealed, but they are all destined to be fired from an AR.
I have a different process, using a Lee Collet die, for 6.5 Grendel cases to be fired in my bolt gun. I also incorporated the expander into my 6.5 Creedmoor loading process.

[@ramsaycountry1177]

I couldn't agree more consistent neck tension is better I important. I run an s-type die with a bushing 0.002 smaller than my buller diameter, then come back with an Expander mandrel 0.001 smaller than my bullet diameter.

[@bryanmarks4070]

I was doing the same thing. It was working good till I started to get carbon rings in my chamber. I noticed that using a bushing die it was leaving a small portion on the bottom of the neck shoulder junction that wasn’t being sized like all bushing dies do. I switched to a regular Hornady FL sizing die with out the expander ball stem then use a expander mandrel. I got better results doing it this was. The regular FL die sizes the whole neck if you know what I mean.

[@ramsaycountry1177]

@@bryanmarks4070 oh yes i know all about that neck Shoulder Junction.

[@linemen71]

Bryan Marks wouldn’t that help align the bullet if a small portion was fire for fit to the chamber?
I know the Redding competition dies hane a micrometer to allow you to size the neck as low as you want. Would you want to go all the way to the junction? Or leave a bit fire formed?

[@bryanmarks4070]

Nick Rewal in the testing I have done it makes no difference. The only difference is the carbon ring takes a lot long to appear when I started sizing the whole neck. I think your ammo has more run out then the little piece on the neck keeping the bullet aligned.

[@dahut3614]

Okay, next random thought: Whether brass being annealed prior to the neck sizing has an effect upon the spring-back of the brass. Having all those sizes would allow you to measure the resulting neck size produced by running a particular mandrel through the case neck.

[@dahut3614]

...and when you find the right neck tension, you can buy the $50 Sinclair carbide one! It will be interesting to see your results.

[@joewoodchuck3824]

Subbed. I've been handloading for quite a while and this guy knows meaningfully more than me.

[@BoltActionReloading]

Welcome Joe!

[@terryhunt4324]

I use the Sinclair on my 30-378 and it works just fine. I also make my own expander mandrels and can make them to the 0001”

[@Dwayne7834]

Thanks for the information. I have some trouble getting the neck tension like I want. It’s going to be interesting to see the outcome of your test results

[@drfroglegs]

Another concern with bushing dies is that it pushes any inconsistencies in neck thickness to the inside of the neck. So if one half of the neck is 0.0005" thicker than the other, the bushing will create an oblong opening to receive the bullet as the bushing pushes the thicker part further in than the thinner part. Mandrel dies keep any inconsistencies in thickness on the outside of the neck.

[@TheRockAdventure]

Exactly! I am waiting now for a neckturner my norma brass in 308w gets anything from 0.002” runout to 0.01 when I have used a mandrel and measure on a seated cartridge

[@paulwatterson5992]

They also make a fantastic concentricity gage.

[@danielcrossland6915]

Good vid. Have you thought of their hydro seater arbour press. I'm sure we can agree on one thing, every step in reloading can be measured somehow for repeatable results

[@3G4Runner_N_Gunner]

Thank you for spending my money for me. Now I have my next step in the never ending money pit that is reloading. I was told I would save money....

[@BoltActionReloading]

I never tell anyone that they are going to save money. You can, but its rare and often doesn't value the reloaders time. Time isn't free IMO. There are very good arguments for ammo you simply cant find (assuming that you can find components)
BAR

[@redrock425]

You can't put a price on fun 😉

[@ThePoacherNo1]

I am certainly no expert, a mere hunter who reloads for fun and I am happy with "hunting precision" in my loads. I crimp all my ammo with the Lee crimp die, would that not create an pretty even neck tension? Is the expander mandrel just something for extended distances target shooters?

[@bishcorp1021]

Excellent channel and thank you for what you do for the reloading community. Im new to reloading rifle ammo and im putting together my setup, to start reloading and fixing to pull the trigger on the 21st Body and mandrels, like most im on a budget and wanted to know how many and which maderls would you start with for 65 Grendel 20inch AR? Thank you for your time and Godspeed!!!

[@boricuaarecibo9259]

Thanks for asking this question I'm in exactly your situation. I just bought brand new hornady 6.5 Grendel brass and I don't have to resize the brass since the shoulder on this new brass is .002 below the highest step of my case gauge but the inside dimension of the necks on my new brass is .257
This will be my very first attempt to making match grade ammo

[@BurnDuration]

As a shooter I understand the definition of “neck tension” however as a mechanical engineer and FEA stress analyst, “neck tension” is not a very accurate term. The expander mandrels plastically deforms the brass creating hoop stress which influences the friction force required to move the bullet. We are inducing residual hoop stresses, and not tensile stresses.

[@duckslayer11000]

Speak English doc. we ain't scientists.

[@slipknnnot]

@@duckslayer11000 this is just a guy telling everyone how smart he is

[@sloboatazmesa309]

@@slipknnnot yup...it's not centrifugal force, it's angular momentum. Insert laughing emojis here...

[@santiagopanzardi3482]

@BurnDuration Neck tension is a reloading term to describe the residual hoop tension between the interference fit of the bullet and the neck OD. But heck, If you really want to add to the conversation, make a simple video showing and describing in a graphical manner hoop stress and/or brass plastic deformation. Followers of this channel would absolutely would appreciate it. Cheers!

[@boricuaarecibo9259]

As a certified dummy I'm having enough trouble understanding neck tension but thank you for the "hoop stress which influences the friction force required to move the bullet " comment I'm so going to use this line at the range 😆

[@wildlandoutdoors51]

Would love to see a comparison between different sizing dies and the mandrels gor consistency

[@blueridgeboy7721]

Dang I wish I knew this like a month ago lol. I just bought some from 21st century.

[@perspicator5779]

Good info!

[@tomashenderson6321]

Thanks!

[@BoltActionReloading]

Your More than welcome tom. Thanks so much for the Super Thanks!

[@Gnolomweb]

Anyone have any clue about the MOA effect this'll have?

[@jonathanjunkala7603]

Your channel is awesome- thank you. I've been reloading for 25 years, and somehow I've missed the benefit of using a Mandrel to get the correct inner diameter of the case mouths. The constant problem with an expander ball is no matter how i try and lubricate it as is reforms the inner diameter- it appears to stretch the case- (especially for large bottle neck cases with small bullets -like 6mm/243) which then requires excess trimming and possible case separation later.. so experimenting with proper Mandrels will reduce this problem?.. and benefit with trying different next tensions- as well as just getting bent case mouths ready for reloading? Thanks in advance for any suggestions. Keep up the great videos- we all learn a lot.

[@tomcooke6670]

What is your process for reloading your once fired brass after you clean and decap. Do you full length resize with expander ball or do you body size without touching the neck and then size the neck with a neck only sizing die. I am looking to use the mandrel approach for 6.5 creedmoor. I have all forster 6.5 dies and Redding 6.5 type s competition die set. It appears I will need to do my resizing in 3 steps. Am I correct. Thanks tom

[@kirkmartin2223]

I personally don't neck size in a stand alone step. There might be merit to doing it that way but if you are full length sizing with a type S die.....I don't see the point in creating a redundant step. I full length size, then mandrel, then seat freedom seeds. Im reloading 300prc and I've not been reloading long so take my opinion as just that.

[@redrock425]

@@kirkmartin2223 That's my take on it. Do you bump the shoulder back too?

[@ironDsteele]

I can see how great these would be when prepping brand new brass. They also give you the advantage of not having to worry about brass thickness as long as it's trimmed and uniform around the case. On fired brass however, I go to my bushing die with the expander removed and use the appropriate bushing to give the right I.D.

[@normanmcneal3605]

I ask you to try the Lee collet neck size die. If you use your fire formed cases in only your rifle, I think you will be amazed. I was

[@jeffreydohl6036]

You say you like charts. I would really like to know what program everyone uses for their charts. I was guessing maybe Excel. I have no idea how to use Excel or what formulas to use.
I'm really interested in making charts for my ladder tests. I want to see where my sweet spots are.
Now I use my Magnitospeed Sporter to get me the numbers and at same time shoot target's to see how they group. But I want to see the graphs.
Jeff D

[@ctech01]

Excel is a great program, and pretty easy to learn. I used this site to learn it for work. Very easy. trumpexcel.com/learn-excel/ and it's free. I use a labRadar so getting my data to excel is simple. There are graphing apps out there that will graph anything you want, but excel is the best. Here is another link, ua-cam.com/video/LT04hiGQzb8/v-deo.html and it pertains to the labRadar, but he will show you how to graph with excel. You will have to manually type in your Velocities and insert them into a graph. Watch this, and you will be able to figure it out. Good luck, I hope this helps you with Excel and graphing.

[@briankording2026]

Like to get some to convert 300 weatherby to 340 brass is much easier to find for 300

[@kpedro161]

I am really learning a great deal from your videos. Thank You! I understand the use you have spoke of here. However I am unclear at what point in the order of operations you are doing this. Are you sizing the Neck at all during your Full Length sizing process then using this to punch out the ID's to desired neck tension?
Keep up the great videos.

[@jonsmith5050]

Its really up to you. For the most benefit in a bolt gun using fired brass from the same rifle, one would neck size, trim if needed, then use the mandrel die.

[@igone209]

You showed the 21st century mandrels fit in the Sinclair die body but Will the 21st century die body be compatible with the Sinclair expander mandrel/next turning tools?

[@alouiciousjackson5812]

21st Century doesn't really support .308. You have to buy the whole kit, the only individual mandrels currently available are for larger calibers. The only individual .308 mandrels are .008 undersize, just to set up for turning. Edit: I found a .306(i.e. .025 tension) SS mandrel from PMA Tool, it's for turning but will work for either. Hollands sells a carbide mandrel that is supposed to give .002 tension(.3065). .307 may be good for bolt guns but not for semi-autos!

[@deputydawg6244]

The book in that link is $4,995!

[@kentrumm1385]

Have you done any test for run out using just the collars vs the mandrels. Also, if the brass is properly annealed, how much spring back do you get with using the mandrels. Thanks and good info in the video.

[@davecollins2097]

That will be somewhat dependent on the alloy makeup of the brass, and how many times it has been fired and if it has been re-annealed or not. Take a piece of your brass, one new, one fired a few times. size it, check it right then, and again, the next day.

[@LCSRacing]

Curious of your process sequence. I.e.. Deprime ,clean, anneal, trim, fl size w/no expanded, then mandel the neck?
Thank you for the content 🙏

[@stuartmarkman769]

B y setting neck tension , does that eliminate the process of crimping the neck?

[@BoltActionReloading]

Hi stuart. I wouldn't call it a replacement for crimping. This is just what you use to set the final neck diameter. It has improved concentricity greatly. I also pretty much don't crimp but that is a personal choice.

[@davidwright5813]

I have the same question as K Pedro and tomcooke6670. When are you full length resizing and when are you only focusing on the neck with the mandrel. Can you list out your process from start to finish?

[@ArmenArmenjs]

He does FL S type by a removing the plunger ball and rod off opt1 to bump the shoulder .001 .002 or opt2 with desired neck tension bushing. Then runs it through 21st C mandrel to correct the concentricity. After you need to measure and trim the brass.

[@boricuaarecibo9259]

I bought this mandrel die it seems light to me

[@BoltActionReloading]

When I made this videobi am pretty sure the only one they offer was stainless. Now I know at the least they have aluminum options, if not the only option. I have some of the new ones that they offer and plan to make a video on them soon

[@ArmenArmenjs]

Question- .6.5 creedmoor using redding S type neck die bushing size .290. Now, I like to have final neck tension of .002. I don't wish to get the entire set, which 21st C expending mandrel is my final step to expand .002 neck tension? and how you arrive to that number?

[@fifd5]

Carbide or are they stainless

[@30Huckleberry]

What would you suggest as a default option in case you didn’t what to buy the whole set? Like 0.002 less than the bullet diameter?

[@BoltActionReloading]

I am going to be doing some testing the next few weeks. So maybe you will be able to glean some info from them. I was using. 002" under projectile diameter initially, but i am going to test them all in 308.

[@Thedrizzle1000]

Would using something like this benefit someone that shoots a AR over just using a standard full length sizer die?

[@BoltActionReloading]

If you want to achieve better concentricity in loaded rounds is something to look at. I have played with Bushins with my AR and had some interesting results here ua-cam.com/video/lCoryif1X08/v-deo.html

[@danielfinke6677]

Does anyone know if the 21st Century mandrels will work with the LE Wilson expander die?

[@Criscuolo94]

Have you ever experienced a slight flare/bell to the case mouth from using these expander mandrels?

[@BoltActionReloading]

It is very slight but yes.

[@Criscuolo94]

@@BoltActionReloading do you do anything afterward to remedy the flare? Like put a crimp on?

[@BoltActionReloading]

No I don't crimp. It has never caused a feeding / function issue for me but it's something to test🤔🤔

[@slightenigma]

Can you use the magnum for normal cartridges ie for reloading -06 and win mag? I like the idea of increasing concentricity. I reload 6,5-06 and use 25-06 brass, and

[@BoltActionReloading]

The only difference that I am aware of is it's 3/4 of an inch longer to accommodate taller cartridges. I would assume so.

[@nilescoyote4829]

Another plus of dry tumbling, no lubrication is needed if you expand afterwards.

[@thecheapshot1065]

I have some Lee 270 Winchester dies and I’m new to reloading the cartridge. A full length resized all the cases before I fired them for the first time in my new rifle the only rifle I intend to use them on in the future. Going forward I have a next size only dye that I’ll be using them on. Some of the cases I found while sitting my bullets have less than ideal neck tension and was wondering how can I go about crimping or tightening the neck tension now that these particular cartridges have been primed powdered and have a projectile in them ? Can I pull the expander and the capping rod out of my die and just use it to compress the neck tension around the bullet or will that not work?

[@372HGS]

With this method do you undersize with a bushing die? Do you also neck turn?

[@BoltActionReloading]

I do not usually neck turn, and you can do either as far as the undersize is concerned. If your die under sizes a lot you may want to consider a bushing.

[@tennis5luv]

Is it difficult to set the dies without a window?

[@BoltActionReloading]

Not Really, but it is nice to see. Depending on your press some may block the window as well.

[@haslefredly6778]

Can I use the Lee Expander die body?

[@sbschuppel8552]

Okay, do you use them before you resize or afterwards ? Nobody seems to explain the proper order to use them when reloading.

[@boxtator5986]

use an expander after you resize the case.

[@sanjuancb]

Timely video! I may have to get a die and mandrel to form .35 Whelen from .30-06 Springfield. For hunting purposes would you recommend a mandrel of the intended bullet diameter or slightly oversize if it is going to be run through a FL sizing die afterwards (.358")?

[@BoltActionReloading]

I haven't used them for forming cases, but I would assume you would want it slightly over size to let the die work?

[@mab0852]

Your die is going to undersize the neck anyway so pull the expander ball/stem out and go with a mandrel .002 under bullet diameter. No need to oversize just to sqeeze it back down again. You might want to 2 stage your step up though and get a mandrel in between the 06 and the 35. I'd recommend getting another useful size .002 under a caliber in the middle like .336.

[@m1a1abrams93]

Just curious but how did you make out ? I would have suggested contacting Redding dies for a forming die also, I also wonder if they would suggest using a different caliber to form with ?

[@sanjuancb]

@@m1a1abrams93 Midsouth got Whelen brass in stock and I said good enough.

[@apro3604]

I know you're busy and may not have time to respond but i'm trying anyway . I am a new reloader on precision shooting and I want your opinion to save some money and buy only few mandrels instead of the full kit for 6.5 , 308 and .22 cal. Please help .

[@BoltActionReloading]

I have seem thr best luck mostly at .002 under cartridge diameter. So for. 264 I use a .262, .308 I use .306. Best of luck

[@stevenkurdziel6870]

Hi. I recently ordered the 21st century expander on your recommendation. But I made the mistake of getting the regular and not the long. I’m reloading 300 win mag. Do you think it is necessary to get the long? I can’t really see why it would be needed?

[@BoltActionReloading]

You just need to make sure you don't crush the case shoulder. Be careful and it will work fine. Hope it works great for you!

[@stevenkurdziel6870]

@@BoltActionReloading I’m new to the mandrel and annealing. For reloading steps would I do?
1. Tumble
2. Decap
3. Anneal
4. Lube & size bumping .002
5. Mandrel
6. Trim, chamfer, & debur
7. Prime, charge, seat bullet.
Thanks again

[@BoltActionReloading]

Hello, My process is decap, tumble, dry, anneal. FL size (no expander) and them run through expander mandrel. Depending on how much carbon is left in the neck you may want something more than dry lube but it works good for me.

[@howardschwartz1462]

I am a newbie to reloading. I am shooting 6.5 creedmoor with a 0.289 bushing. Do I then use the expander mandrel or wait until am ready to seat the bullet. Thanks. Hope to hear from you.

[@BoltActionReloading]

Hi Howard, I am not 100% sure what you are asking, but if you like you can certainly size with a bushing and then use the expander. I am not sure of your brass thickness or the neck tension that you are hoping to run. Usually a 289 bushing is pretty close on its own.

[@howardschwartz1462]

@@BoltActionReloading thanks. You answered my question

[@dragonflyfab9703]

Are the die bodies caliper specific or neck specific?

[@BoltActionReloading]

The die bodies all take the same mandrels. The only difference is that the EL version is longer so you can set them to a height where you don't have to worry about smashing the neck of the case in the top of the die.

[@dragonflyfab9703]

@@BoltActionReloading Are 6.5 grendel, 6.5 creed, and 6.5 prc all the same

[@BoltActionReloading]

I believe you could all use the regular body and you can use the same mandrels in all those cases.

[@davidlayne8755]

For the price they should be carbide, come on now...

[@jasonmorgan27]

gf