How to Easily Set Consistent Case Neck Tension - 21st Century Expanders

In this video I cover the easiest way to set consistent case neck tension with your reloads. I review the different expanders that are offered and show how using different expanders change the case neck tension and how it affected the performance.
Neck Tension Playlist: • Proper Neck Tension - ...
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[@BoltActionReloading]

Want to see more Neck Tension testing? - kzbin.info/www/bejne/hX6ommibfbl_rrM

[@MD-MDMDMD]

After watching a number of your videos around neck tension I bought the small 21st century die body and just a single .222 and .262 size mandrel for my 223 and 6.5 PRC. I ran a test using the 223 between expander ball vs mandrel. 20 rounds each in 4x 5 shot groups. I noticed a .2 of an inch drop in group size with the mandrel groups. So where I got a .7 inch group on the expander ball, I got a .5 inch group on the mandrel. Very happy with that. So I've now made this part of my case prerp process. I do not own an annealer.

[@tucobenedicto1780]

Great video. I used to never believe in expander mandrels, but now all my sizing dies have the decapper & expander ball removed and I use a Lee decapper & PMA tool expander for every rifle cartridge.

[@WvMnts]

Thank You!! Just got these ordered. Appreciate the videos much

[@hulley5223]

Please do a video on when to experiment with neck tension in the load development process. What comes first: 1) charge weight, 2) best powder & primer combination, 3) determining ideal neck tension?

[@hardball107]

IMHO you would want to do your brass prep first. Trim, deburr flash holes and turn the necks for consistency. Then work on powder and bullet seating length (COL) until you find a good accuracy node. Run a couple different primers next to look for a change and pick one that works best and then play with neck tension and look for improvement's. Keep good records and when you start playing with neck tension and find improvement's you will be able to point directly to that and not confuse it with some other process.

[@dgott7726]

This would be a good video. Put all the steps in order... then leave links to your videos on each step in the description

[@perspicator5779]

Great info! To the point! No blah, blah! Really enjoying your channel! (No stupid distracting music either.) Kudos!

[@BoltActionReloading]

I appreciate that!

[@hardball107]

I have been amazed at the difference neck turning and being consistent with bullet seating have made. I have a Savage 12FV in 6.5 Creedmoor with a Vortex 6x24x50 Diamondback Tactical scope on it. I neck turn all my brass to a neck thickness of .0145" which means almost all necks have full length contact with the cutter. I then polish the expander ball in my resize die to a mirror finish most times ending up with a .002 undersize finished diameter. I have gone as far as to have custom expander balls made with elongated entrance and exit ramps and all polished for smooth operation. The key is consistency and I anneal after 5 loadings. Currently that rifle, Tupperware stock and all with my 120gr IMR4350 handloads will shoot sub 3/8 moa 5 shot groups at 100 yards as long as I don't screw up. My best so far is .342", ringing 8" steel at 600 yards is like phoning home. I spend most of my time reloading on brass prep and cleaning right down to bore scoping the barrel. Just for fun I loaded 50 rounds without any brass prep except for trimming and a flash hole deburr. I shot 10 - 5 round groups and found not only did the groups open up to just under 1 moa but the velocity and spreads were all over the place comparatively. IMHO there is a lot to be said for attention being paid to the resizing (I use a .002" bump to the shoulder) and stabilizing the neck tension and dimension's any way you want to do it. It could be the difference between a good shooting rifle and one that leaves just 1 ragged hole in the target.

[@yukon4545]

Glen was the bomb. Learned a lot from him. Between him and Mic McPherson, changed my whole approach to Handloading.

[@lemonaid1605]

I enjoyed watching, anther high quality informative video. Your mention of Zediker and the forces on the case brings me this question. Does using mandrels cause less case stretch than traditional standard dies?

[@jheasley1]

This video was very educational and interesting👍👍

[@mumblesmunchies9874]

I’m new to reload it and I love your channel. What is your current reloading process please.

[@rgibson759]

Great info :)

[@E.L.RipleyAtNostromo]

I bought the 21st Century black nitride turning arbors in .22 and .30 and they are listed as .002” under bullet diameter only. As you say they now offer the trad expander mandrels in black nitride which are .001 under, but I’d be inclined then to just get the whole set and dry lube the steel. However, I thought I’d get the .002 under to start. I tried to buy the stainless Sinclair expander mandrel die body that handles up to .338, but they were out of stock (back in stock at Brownell’s 1-12-23) because they have an o-ring that floats the mandrel more, but am impressed with the 21st century quality. The arbor is slightly loose in the die body, which I think serves the same function as the o-ring in the Sinclair, allowing the mandrel/arbor to float.

[@xxshiftlockxx]

I've noticed that with my Lapua 6.5 PRC brass, after firing, corncob media tumbling, annealing, Redding S die with SAC .290 bushing, then with the .2625 mandrel, it actually gauges .262 with my pin gauge. So there seems to be about a .0005 spring back in the brass. I also dip my cases in Redding dry neck lube before running the brass through the mandrel.

[@Iscariot18]

Forester came out with a neat Neck tension gauge. For .223 I was using LE Wilson Expander mandrel (.223) size. Using the gauge it actually read .222 after Mandrel, not .223 like what I would assume.

[@rotasaustralis]

If the cases are annealed, neck turned or both, setting neck tension by dimension will still provide a consistent seating pressure but not the same seating pressure as cases which are not annealed, neck turned or both. I set my seating force via a seating force gage & adjust the dimensions of the neck to suit.

[@stevestrapac3056]

I noticed you didn’t mention the Lyman M die the late, great author Dean Grendel dawned over in the 1980’s… I came to your solution via the M die because I noticed the dies (at the time) would actually stretch.233 REM brass as much as 0.006”, and cause issues. The .308 cal M Die I use for 30-06 and 300WM measures 0.305”, btw. But I am going to buy the 21st century expander kit for sure! The l concept of inside sizing the neck on the down stroke is far superior!!

[@mckimmym]

I’ve almost got everything I need to start reloading for my 6.5 prc, just waiting on a body comparator. I went with the 21st century gen x with .263 mandrel. First I’ll size my 1F Norma brass with a Hornady match grade die and a .289 bushing. Hopefully it performs great on the first try but I have a feeling I’ll be buying more mandrels in the future ;)

[@ErikisOfficial]

Its been a year. Hopefully you haven't gotten so scientific about it that the actual of shooting hasn't slipped away

[@mckimmym]

@@ErikisOfficial Lots and lots of shooting. 1 year later and the barrel is nearly burnt up. Somewhere around 700-800 rounds through the barrel with load development, PRS matches and plinking. I'll be swapping it over to a 6mm ARC barrel next for lower recoil and longer barrel life.

[@skipper9400]

I have been using a precision honed Forster full-length die with NO expander, and then using a 21st Century mandrel ....seems to work VERY well, and a lot less Runout......OnWard.....

[@hugohmtz1]

I’m starting to reload and I have found your videos very educative. Stupid question but I have to do it. Will be ok to run first an expander mandrel and then a neck size bushing? Or makes absolutely no sense? Thanks.

[@devineutsler7286]

I am not an expert, but I will give this a shot. When you full length size, you should be bumping the shoulder of the fired brass back about 0.002". While doing this, the expander ball goes in the neck, opening it up first. Then the die sizes the body, shoulder, and closes the neck more than necessary. Then on the up stroke, the expander comes back through the neck opening it back up, and possibly pulling up on the shoulder of the brass, eliminating the 0.002" shoulder bump that you just did all of this for. AND all of this action is work hardening your brass. So the short answer to your question is to not use your expander mandrel at all.

[@derekmcmurry4263]

In my experience the best way to get consistent neck tension is to not use any type of expander at all. Simply use a bushing and reduce OD .0015 to .002 less than loaded ammo. This also greatly reduces runout

[@terryolsen3225]

Do you recommend any other reloading books? Top Grade Ammo is out of print. Thanks.

[@billyloyd2486]

What are your thoughts on the Promethius balance?

[@ashiha13]

What are you doing to get the neck smaller than the diameter of the bullet in the first place? After firing it seems to always be oversized. So is a bushing die being used to first reduce the size before then expanding it back out? If so, how much do you need to go below the size of the expander to prevent bounce-back?

[@a-a-ron4679]

Is it a waste of time to resize with a bushing and then following up with an expander mandrel? I have both the Redding S type F/L with the expander ball removed and 21st century body and mandrels

[@DVEarley1995]

General Question: Will a cooler running carbon wrapped barrel translate to a cooler suppressor? Thank you

[@gascheck8151]

For consistent bullet release place projectiles in a pan and spray lightly with Hornady One Shot Lube. Do all steps as shown in video with 21st century expander dies.

[@anthonyz.4560]

Is the black nitride worth the price difference over stainless?

[@randyemenhiser2573]

I want to know where you got that shirt!

[@mab0852]

I want the minimal cold working I can get so my goal is really for my mandrel to be the purely redundant. I have my Forster die honed .0025 under and then use a .002 under mandrel just to push any minimal thickness differences back to the outside. In a perfect world I wouldn't need or use the mandrel, but we all know that's not how it really works. Plus it saves a lot of egged or dinged necks.

[@GeographyNerd48]

I got the black 21st century with the window. The window is worth the price. Wish they made the 17 and 20 cal mandrels that dont require neck lube.

[@yojimbo05]

Do you have a copy or know where to get a copy of Top Grade Ammo by Zenidker. I know he passed away and his publication has shutdown :( any help would be greatly appreciated

[@jonleone777]

What size madrel would you recommend for a 223 in an ar15. Im thinking about .003 under

[@BoltActionReloading]

I did some testing in this video on 223. But .003 under will work fine I am sure. kzbin.info/www/bejne/faPYgaWbnqmKiac

[@stevehigdon326]

I know this is probably a stupid question, but how can I verify the inside neck diameter exactly using the pin gauges? Obviously a .306 pin gauge will not fit into a .306 opening. At least, not the ones I have. What am I doing wrong?

[@BoltActionReloading]

If your brass is properly chamfered if would fit. (Depending on what the actual dimension is and if you have a plus or minus pin gauge.) But I assume you are dealing with some type of spring back. I have been able to put the appropriate pin gauge in the bushings with the same labeling. Hope this helps.

[@howardschwartz1462]

Do you recommend neck turning to even out case diameter inconsistencies?

[@BoltActionReloading]

I guess it depends how good your brass is. Overall I think that too often the brass is already pretty good and its very difficult to improve it by turning.

[@howardschwartz1462]

@@BoltActionReloading thanks.

[@cornbreadburgess1950]

👍❤️

[@aaronwilcox6417]

This reloading process is fascinating but honestly its tool and Guage intensive as well as technique intensive. It's complicated to be getting into.

[@hulley5223]

F-Class John just came out with a video talking about using diamond compounds to put a glass-smooth finish on expander mandrels and gauge pins to prevent scratching the inside of case necks. What are your thoughts on this?

[@Mrjaspgu]

I just used the 21st century mandrel last night on new brass and there are brass lines on the mandrel that catch my fingernail. I'm sure the inside of the necks are no longer smooth. What do I do to prevent this? Chamfer and debur before using the mandrel?

[@skipper9400]

@@Mrjaspgu I use dry graphite on the neck, (Imperial Dry Neck Lube)....however, you have to be careful to not get any of the little white balls stuck to the inside of the necks.....OnWard.....

[@Wk-is8eh]

@@Mrjaspgu You could get a carbide expander mandrel. I have one from PMA tool and it's great, but you pay for it at $60 a mandrel. I believe Brownells also offers carbide mandrels. I've also found that Hornady One Shot works really good as mandrel and case neck lube. I spray some on the mandrel then spray some on a q tip and swab the case neck.

[@hardball107]

Most times I find expander balls to be a little under .002" undersize so I use very fine Clover Compound to polish them in a drill press. You end up with much smoother operation and less working the brass.

[@richrudley2650]

F-Class John uses carbide expanders. Stainless steel expanders will gouge after awhile.

[@ctech01]

That's how I milk it. I love my 21st Century expanding mandrels. 👍👍👍👍👍👀😎

[@mightyarmoryprecision]

We’ll said

[@paulwhelan3228]

Has anybody ordered from 21st century? I tried to order. Website would not let me check out. The site did not save my cart. I had to keep reentering my items in the carts. Tried several times. Did anybody leran the secret?

[@lonniemcmanners6296]

Neck tension would be a molecular study per case. Anything else is just wishful thinking

[@thatguyoverthere2288]

Why you singling me out?!

[@nonetheless01]

I don't care how you describe it , I just don't see the difference of pulling the neck over a sizing button and pushing the neck over a mandrel , I don't see how it makes a difference if both are the same diameter.

[@stevestrapac3056]

Pushing with an expander doesn’t stretch the brass like “pulling” it over a button does.

[@nonetheless01]

@stevestrapac3056 the buttons are tapered and if they "pull" then the expanders "push" come on .

[@stevestrapac3056]

@@nonetheless01because I don’t get the compressing of the case like I get with the old school button. The M die fixed the problem of stretching, without any associated problem with compressing the case. I’d imagine that a newer carbide type tapered expander would reduce it. Those are just the results I had loading for a mini-14…

[@nonetheless01]

@stevestrapac3056 I understand what your saying I have been loading for 28 years now and I have seen others make similar claims but I like to test eveytingbi can I can't duplicate with measurement what your claiming here , maybe there is something in my process that stops it but a lot of reloading products are a solution in search of problem but most guys just buy in and believe without testing .