I see Sinclair now offers carbide expander mandrels. Who here uses and expander mandrel or neck turn mandrel? Of the two, which do you prefer? What measurable difference did you see? What does your process look like? Trying to decide if it's worth trying out.
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Who uses an expander mandrel?
- Thread starter Winny94
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Most people use a turning mandrel as it’s .002 under the bullet diameter. Expander is o to .001.
Here’s when I asked a bunch of these same questions
Here’s when I asked a bunch of these same questions
Just bought one to run on my press this spring.
21st Century TiN turning mandrel for .308.
Bought as a remedy for my concern my Dillon Rapid Trim leaves my brass necks too tight.
Noticeable difference seating now.
Still doing load development but based on results in .308 got setups for my .223 and 30-06 tool heads.
21st Century TiN turning mandrel for .308.
Bought as a remedy for my concern my Dillon Rapid Trim leaves my brass necks too tight.
Noticeable difference seating now.
Still doing load development but based on results in .308 got setups for my .223 and 30-06 tool heads.
I use an expander mandrel. It's the only way to seat new Lapua .308's. and if you use a Dillon trimmer, that trimmer die is also a sizing die but has no expansion ring so using a mandrel after that will give you sized and uniform case mouths. A Dillon 650 really speeds things up, especially in prep.
In general I don't need a mandrel unless I'm using new Lapua brass or if I'm using the trim die as a size die too. Usually once fired brass gets resized and I don't need a mandrel for that, just a sizing die. So it depends on how I setup my toolheads and whether brass is new or once fired.
In general I don't need a mandrel unless I'm using new Lapua brass or if I'm using the trim die as a size die too. Usually once fired brass gets resized and I don't need a mandrel for that, just a sizing die. So it depends on how I setup my toolheads and whether brass is new or once fired.
All my brass prep from 223 to match brass is the same. Full length non-bushing die to size the outside of the case, followed by an expander mandrel in a separate die to set final neck tension. I do mine on Dillon presses, but you could do it on a single stage with two passes if you wanted to.
Ideally the FL die doesn't make the neck diameter overly small so it's not overworking the brass, but it's not super critical. I have Forster dies that have a honed neck diameter to perfectly match the expander mandrel, and I also have Forster dies that are not honed and size the case about 0.004 more than needed. Both processes make nice consistent low runout cases.
I just did 2k pieces of Lake City brass this weekend with a stock Forster 223 die and an Sinclair mandrel on a Dillon 1050 and it all came out dead nuts straight with less than 0.001 runout.
As far as which mandrel, I like 0.002 "turning" mandrels. I have both Sinclair carbide and 21st Century titanium mandrels, both work well but the 21st century are a lot cheaper.
Wet Tumble, Anneal, Lube and Size with Redding FL S Bushing, Expander Mandrel, Tumble Dry, Trim C&D, Prime, Powder, Graphite Lube, and Seat Bullet.
I set the neck bushing so that I can just feel the expander mandrel. If I feel inconsistencies, I pull the brass and throw it in with the dirty brass to be reprocessed.
Why the expander, because of spring back. I have both the carbide turning and steel expander. I'll test 5 rounds each next time I go out. I'll bet there is not much noticeable difference.
I set the neck bushing so that I can just feel the expander mandrel. If I feel inconsistencies, I pull the brass and throw it in with the dirty brass to be reprocessed.
Why the expander, because of spring back. I have both the carbide turning and steel expander. I'll test 5 rounds each next time I go out. I'll bet there is not much noticeable difference.
I have both steel neck turn and expander mandrels for 6mm and 6.5. I've settled on the expander mandrel for giving me sufficient tension and I used a powdered graphite lube when running the case mouths over the mandrel. The mandrel plus the Redding FL type S die gives me good consistency for neck tension and I believe it's helping me get my SD's down. Last ladder for the 6.5CM had a node with single digit SD's. Finally. Lapua brass.
I can’t speak to a carbide mandrel but my redding carbide ball is noticeably smoother than the normal steel ball.
And Ill preface this by saying that I spray adequately into the necks but I can’t tell any difference between my steel and TiN mandrels but I have 3 TiN and only 1 steel. I justified going for the TiN mainly because all of them were roughly the same as one carbide. The lone steel was just to test between the two. Not a whole lot.
I can't tell a difference between my TiN and carbide mandrels. My steel mandrels were higher resistance and more prone to galling.
I use the TiN turning manderal from 21st and it has been a very nice addition. I am on a single stage press so it is a two step process and I wouldn't go back. You can bet a progressive press has jumped to the top of my list though.
I would still lube them with tin, running dry you can feel it dragging.
Same as Del Bando. Full length size with a bushing to set the neck at 0.003", run through the mandrel to set the neck at 0.002", trim/chamfer/debur on my Giraud, then do my priming, powder, seating. The only difference is i'm not using a spray lube
Imperial wax on the outside? I would just keep that on the body and give the neck a dip in the graphite media if so.
Mandrel after FL sizing (no expander ball in FL die).
I lube by throwing all the cases into a big open tupperware tub, spraying them with alcohol/lanolin lube, then swishing them around by hand and spray again, etc until they're coated. I actually try to keep the lube out of the inside of the neck when spraying but I'm sure some residue gets in there. I'm doing anywhere between 100 and 500 at a time. No way I would want to hand dip each case in neck lube.
I lube by throwing all the cases into a big open tupperware tub, spraying them with alcohol/lanolin lube, then swishing them around by hand and spray again, etc until they're coated. I actually try to keep the lube out of the inside of the neck when spraying but I'm sure some residue gets in there. I'm doing anywhere between 100 and 500 at a time. No way I would want to hand dip each case in neck lube.
I use Redding FL with .287 bushing for a 6.5semi which is 0.003 from a loaded round with Hornady brass. If I wanted to use the expander die would i have to get maybe a .285 or .286 bushing to use it with the .263 mandrel or the .287 will be fine? I'm pretty happy with the ES and SD i get with the 6.5x47, 260 and 308 bolt actions but the 6.5semi could def improve.
Imperial wax on the outside? I would just keep that on the body and give the neck a dip in the graphite media if so.
Yeah, Imperial on the outside and I made something similar to the kit. I took a small jar and filled it with graphite and some very small ball bearings, like 1mm in diameter. It does ok, but if the TiN mandrels are better, I'll take a look at them.
How do you tell if you’re “galling”? I’ve run my Sinclair neck turn mandrels with and without neck lube and couldn’t feel much of a difference. As a result i stopped using the Redding Media because it was messy and I couldnt clearly see a difference in performance after using it.
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My mandrel has sort of a burnished look now, but no brass build up. So is one considered “ok“ if the build up isn’t occurring?
I've started doing exactly this and I'm very happy with the results. Only difference is I toss all the brass in large ziplock and hit it with Hornady One Shot case lube. Like you I don't try to lube the inside of the necks.
I think I know the answer, but figured I'd crowd source some confidence.
Have 300pcs of 6.5x47L that come out of my Redding FL sizing die with carbide expander button at 2.885 OD. Load was developed with virgin brass that had a 2.890 OD and gave me .002 neck tension.
I basically want to just push any inconsistency to the outside of the case without really expanding it further.
While I'm thinking the carbide expander button would have left me with a concentric inside neck, any input on the idea/need to run the stainless steel expander mandrel, which would give me less expansion than the turning mandrel, barely into the neck.
Have 300pcs of 6.5x47L that come out of my Redding FL sizing die with carbide expander button at 2.885 OD. Load was developed with virgin brass that had a 2.890 OD and gave me .002 neck tension.
I basically want to just push any inconsistency to the outside of the case without really expanding it further.
While I'm thinking the carbide expander button would have left me with a concentric inside neck, any input on the idea/need to run the stainless steel expander mandrel, which would give me less expansion than the turning mandrel, barely into the neck.
No need to run an expander mandrel after using a the expander button in your die. They both do the same thing so it's an either/or. The reason to use to separate expander mandrel instead of a expander button is that sizing top down instead of on the upstroke will generally make for straighter cases with less runout.
If you want to use an expander mandrel, pull the carbide button out of your die.
If you want to use an expander mandrel, pull the carbide button out of your die.
That's what I figured.
Got the Redding non-bushing FL sizing die before I knew about bushing dies and figured I'd see what it gave me as far as neck OD before I went the two step route with the mandrel and buying a bushing die for 6.5x47L.
Got the Redding non-bushing FL sizing die before I knew about bushing dies and figured I'd see what it gave me as far as neck OD before I went the two step route with the mandrel and buying a bushing die for 6.5x47L.
To better understand why a bunch of us use honed FL dies and expanders, you want to measure the OD of the neck on 1x brass that was fired in your gun and write that number down. Now completely remove your decapping rod/expander assembly from your Redding FL sizing die and size that case. If your die is setup properly, it will bump the shoulder back to whatever you have the die setup (.001-.003) for the bump and squeeze the neck down and thats it. Now measure the OD of that neck again. Most times, you will find that FL sizing die squeezed that neck down WAY too much which in turn requires the expander ball (or expander mandrel if your not using the ball) to open the neck way back up. This overworks the brass and can cause concentricity issues. Die companies do this so that FL sizing dies can be used with many different brands of brass which have varying neck wall thickness.
So, if you measure the OD of a loaded round, subtract .002 for neck tension I usually like my FL honed Forster die to be squeezing the neck down .004 under loaded round. That way the expander mandrel only has to open the neck back up .002 to give you your final neck tension.
Now, for example, my Forster .223rem FL sizing die, before honed, would squeeze the neck of LC and Lapua brass down about .012 under loaded neck diameter. Then the expander ball (or mandrel) would have to open that neck back up .008-.010 to give me my desired .002 neck tension. That is completely unnecessary for my purposes. So what I did was have that die honed to squeeze the neck .004 under loaded. Its now a 2 step process on my 550 for my Lapua bolt gun brass. Bump shoulder .001 and squeeze neck down .004 then run the brass through my 21st Century TiN Turning mandrel to open back up .002. This makes brass that has virtually no runout, measured .0005 or less on my 21st Century Concentricity gauge.
Now, we will get people to chime in that say I use a RCBS FL sizing die, or bushing die, etc, etc, etc and my ammo shoots bug holes and my SD are 1. Thats fine, everyone has their own process and I say use what works for you. I own all the dies, Redding, Whidden, RCBS, Hornady, Forster, etc. Ive used bushings, FL, Mandrels, Collet, etc.
I find this process to produce the most consistent ammo of all the dies and methods Ive tried over the years. I no longer load on my Co-Ax. I process brass on my XL650 in one step in large batches and put in bins so they are ready to load when I need them. I load most rifle rounds on my 550 with the exception of 223 AR15 precision rounds on my 650.
Here is what I explained above in numbers form for those that grasp things better visually vs reading:
Example from Lapua brass in 223 Wylde TL3/Kreiger 26" Bolt Gun
0.253 - Fired Case Neck OD
0.247 - Loaded Case Neck OD
0.245 - Final sized Neck OD with .002 neck tension after mandrel
0.243 - Neck OD after run through Forster FL Honed die
**NOTE**
The fired case neck OD vs loaded case Neck OD will differ depending on what reamer was used. You can see the brass fired in this Kreiger barrel opens expands .006 from loaded round neck diameter. I have another 26" Mullerworks .223 barrel for this same gun done by Greg @ Southern Precision/Bugholes which he used what he calls his own variation of a .223 Rem Match reamer. The neck on that brass only expands .004 when fired which some will say works the brass even less. Dont get hung up on the fired case neck OD measurement. I just mentioned that so you can see how much your non-honed FL sizing die is squeezing that neck down.
I hope this post helps people make a decision when they ask what die, should I use an expander or bushing or FL sizing die. We get this post almost weekly and I hope this answer why. I find it easier to buy $36 Forster FL sizing dies for each rifle (AR15 5.56 and .223rem) and have them honed to that rifle then put them in a dedicated brass prep toolhead.
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Padom
Thank you for the very detailed and digestible post. Other information you’ve posted like the above has assisted me in other decision making and this is another example of a well composed piece of prose.
Your point about overworking the case neck by using an unhoned, non-bushing FL sizing die is noted and I fully expect to get fewer cycles from these 304pcs of Lapua brass using the unhoned Redding FL resizing die with carbide expander in place.
That said, I’m now the father of a 2.5 month old and the number of rounds sent downrange has been cut drastically since 14 July as has the time available for brass prep (and every other thing that isn’t kiddo related).
In this instance, l think I’ll remove the additional step of using a mandrel to expand and true the inside the necks at the cost of losing these 304pcs of 6.5x47L brass earlier than would be possible with a bushing die or honed FL resizing die.
Life is a constant game of cost:benefit analysis and, in this case, so long as the ES/SD and groups hold or improve, using the standard FL resizing die and forgoing a mandrel looks to be my way ahead.
Still planning to use the mandrel on my .223 and .308 brass that’s processed on my Dillon 650 as it’s just another die to set up in an already easy situation, but I do my 6.5x47L work on a single stage. Might move it to the 650 one day; in which case I’d revisit the current FL resizing die.
Thanks again the for the detailed response. Always enjoy reading your input.
Cheers
Eric
Thank you for the very detailed and digestible post. Other information you’ve posted like the above has assisted me in other decision making and this is another example of a well composed piece of prose.
Your point about overworking the case neck by using an unhoned, non-bushing FL sizing die is noted and I fully expect to get fewer cycles from these 304pcs of Lapua brass using the unhoned Redding FL resizing die with carbide expander in place.
That said, I’m now the father of a 2.5 month old and the number of rounds sent downrange has been cut drastically since 14 July as has the time available for brass prep (and every other thing that isn’t kiddo related).
In this instance, l think I’ll remove the additional step of using a mandrel to expand and true the inside the necks at the cost of losing these 304pcs of 6.5x47L brass earlier than would be possible with a bushing die or honed FL resizing die.
Life is a constant game of cost:benefit analysis and, in this case, so long as the ES/SD and groups hold or improve, using the standard FL resizing die and forgoing a mandrel looks to be my way ahead.
Still planning to use the mandrel on my .223 and .308 brass that’s processed on my Dillon 650 as it’s just another die to set up in an already easy situation, but I do my 6.5x47L work on a single stage. Might move it to the 650 one day; in which case I’d revisit the current FL resizing die.
Thanks again the for the detailed response. Always enjoy reading your input.
Cheers
Eric
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