I am pretty new to reloading. I have pretty fresh brass- all my brass is fired 2 times. 50% lapua, 50% hornady. I use Forster FL sizing die. After FL sizing should I work separately on the neck and use another die to set up a predefined neck tension? Is it mandatory practice to work on the neck every single time if my aim is to stay sub-moa at 300 and 600 yards? If this is the case, which tool should I use to get consistent neck tension?
Neck tension control
- Thread starter Oldmauser
- Start date
For starters, I don't know how much brass you have in total, or of each. Having used nothing but Lapua for many years now, I'd at least segregate the two brands and reload/shoot only one brand at a time. My choice would be to remove the Hornady from the equation entirely. At least then, you'd be getting consistent neck tension results by using all of the same brand.
I neck size only (a controversial subject here) for .223R, 6x47L and .308W. I don't do hot loads for anything. I've gotten 20 reloads on my .308W Lapua before I voluntarily retired it. I imagine it could have gone another 10, maybe 20 reloads, but I had gotten more than my money's worth out of it. I didn't throw it away, I bagged it up, marked it as retired and put it back on the shelf. I wouldn't have any concerns about using it again if I had to.
YMMV......
I neck size only (a controversial subject here) for .223R, 6x47L and .308W. I don't do hot loads for anything. I've gotten 20 reloads on my .308W Lapua before I voluntarily retired it. I imagine it could have gone another 10, maybe 20 reloads, but I had gotten more than my money's worth out of it. I didn't throw it away, I bagged it up, marked it as retired and put it back on the shelf. I wouldn't have any concerns about using it again if I had to.
YMMV......
Thank you. I plan to stay with FL sizing. My question is, should I apart from FL sizing do anything else to neck of the brass. I plan to use only lapua brass. So, does forster FL die provide enough consistency in neck tension or should I run extra every time e.g lee collet or wilson mandrel die or something else?
As the guy above said, you can look at replacing your mandrel to give you the neck tension you desire, or how I and many others do it is use a bushing type die. The bushing I get is the neck tension I want plus .001 for spring back.
I suppose you could also use a body die and one of those Lee collet dies, but I never had success with getting the neck tension I need with them. Maybe Lee does custom mandrel sizes.
Like was said above
I use both lee collet/Redding body die or Redding sizers with bushings. The lee collet are my favorite of the two and provide low runout and .0015 neck tension. I use them for 6.5CM/260/308/300 WM.
I agree with using just the Lapua brass. I tried some hornady in the past but switched everything to Lapua or Nosler now. Just don’t use both brands at the same time.
For my setup I anneal every firing. Neck size with lee collet die. Body size with Redding body die (or use Redding FL bushing die)
The less you work the neck during sizing the better
I use both lee collet/Redding body die or Redding sizers with bushings. The lee collet are my favorite of the two and provide low runout and .0015 neck tension. I use them for 6.5CM/260/308/300 WM.
I agree with using just the Lapua brass. I tried some hornady in the past but switched everything to Lapua or Nosler now. Just don’t use both brands at the same time.
For my setup I anneal every firing. Neck size with lee collet die. Body size with Redding body die (or use Redding FL bushing die)
The less you work the neck during sizing the better
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Not maybe. They will make you a mandrel in whatever size you want. I like .003” under bullet diameter, get .002” neck tension after spring back.
Redding FL type s and Hornady match grade depending what cartridge for bushing dies is what I got/use
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I decap, tumble, the resize with a Redding full length bushing die,slighty floating bushing, a tad smaller then final opening size objective, with no decapper or expander ball in die, then run them over a mandrel to set neck tension to .002.
My last loads the run-outs are less than .0005 at the ogive.
My last loads the run-outs are less than .0005 at the ogive.
If you fl size, just check the interference fit. .002 I use and get that with my fl dies. It works out for me with the components I have.
I took a while to learn to keep my stuff clean and lube neck in and out. Work hardening is another subject.
I took a while to learn to keep my stuff clean and lube neck in and out. Work hardening is another subject.
only if you follow up with an expander mandrel.
The mandrel in the collet die is not shaped well for the job of expanding necks. A proper expander mandrel is way better.
in this process, you would use the collet die to size the neck, then run the case through the FL die with the expander assembly removed, then open up the neck with a mandrel. This would produce the most concentric ammo.
most people would skip the collet die and just go with the FL die followed by a mandrel. But that process isn’t as consistent as the first.
Send Whidden a couple fired cases and they will make you a die to whatever you want to spec it out to (.015 - .03 neck tension). John Whidden has won more big high power matches in the US in the last 10 years than anyone, and he uses a non-bushing FL die for sizing his brass. The only thing you may have to adjust for down the road is a different lot of Lapua brass that might have slightly thicker/thinner necks. You can always buy a mandrel to adjust for that.
Add a zero there.
another FL siding advocate. It’s simple all you have to do is confirm your set up.
another FL siding advocate. It’s simple all you have to do is confirm your set up.
amazing what happens after a couple fingers of good scotch...
I use the Hornady Match Grade dies for 6mm Creedmoor, the sizing die is a FL with a bushing (I use a .269” bushing as my loaded neck OD is .273, no expander ball, so ~.002-.003 neck tension with spring back)... honestly worked pretty good for a while, but I felt like if I could get just a bit more consistent seating pressure/feel every time, that might equate to more consistent neck tension...
So I got and now use a Sinclair Mandrel Die with their TiN Turning Mandrel (.241”, their “turning” mandrels are -.002” under bullet OD while their “expander” mandrels are just -.001”) after going through the FL Bushing die: seating bullets is now very consistent case to case and smooth as butter... it literally cut my SD’s in half and my groups at distance have shrunk!
I’m a believer in the mandrel thing for sure!
IMHO, I don’t think it might matter very much between using a good FL sizing die vs a FL+bushing die... using the mandrel is probably the special sauce for more consistent neck tension with either.
What’s cool about using the mandrel after sizing is that if the neck dimension is already good it doesn’t really do anything, it just uniforms the necks that aren’t quite there yet and do need a little more love lol.
So I got and now use a Sinclair Mandrel Die with their TiN Turning Mandrel (.241”, their “turning” mandrels are -.002” under bullet OD while their “expander” mandrels are just -.001”) after going through the FL Bushing die: seating bullets is now very consistent case to case and smooth as butter... it literally cut my SD’s in half and my groups at distance have shrunk!
I’m a believer in the mandrel thing for sure!
IMHO, I don’t think it might matter very much between using a good FL sizing die vs a FL+bushing die... using the mandrel is probably the special sauce for more consistent neck tension with either.
What’s cool about using the mandrel after sizing is that if the neck dimension is already good it doesn’t really do anything, it just uniforms the necks that aren’t quite there yet and do need a little more love lol.
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Can you feel the difference in neck tension when you seat the bullet? I’m having problems with consistency on my seating depths and general consensus is that my neck tension is to blame. When I seat my bullets some feel much stiffer than others.
You can feel a few things that differ from neck to neck when seating a bullet, yes. Neck tension being one of them.
If using the Lee neck sizing die then a Redding body die makes the most sense.
Lee die does the neck only (has to be sized after every firing to get correct neck tension)
Redding body die sizes the body only (can be used every time or every few times but the bolt will be harder to close if not used)
You could test Lee neck only (no body sizing) and Lee neck & Redding body to see which your rifle prefers.
Yeah, that's exactly what you want to try and fix: you want the seating feel to be as similar as possible case to case when seating bullets. That usually will mean your neck tension is consistent too.
Before switching to using the mandrel following sizing, I'd say when seating bullets on 100 rounds: maybe a good chunk of them would feel about the same, but not all of them, as a pretty good chunk would still be kind of all over the place in feel, with some being easier and some feeling stiffer...
So before getting the mandrel I did a sort of "mini-experiment" a few times where I'd place all the rounds where seating felt good and about the same as each other into one box, and then the other ones that weren't really as consistent feeling into another box...
It doesn't take much shooting at all to quickly figure out that the ones that all felt good and "about the same" as far as bullet seating feel will group better, and be way better than the other ones that didn't feel consistent to one and other.
You can literally see it in your groups: average mean radius, ES, and average-to-center will all be smaller than the groups shot with the rounds that felt inconsistent when seating bullets, and the impacts will stay nice and tidy as far as printing vertically with the consistent ones as long as your powder charges are consistent too. You'll see it at your chrono too, as your SD numbers will be looking good and be lower with the consistent ones vs the less consistent ones.
Now, using the mandrel after sizing, when seating bullets on 100 rounds, ~90 of them will feel about the same as the next, and the maybe ~10 or so that might feel just a little off from the others are so close in feel that it's more or less a non-issue and almost not worth mentioning...
***Since it hasn't been said, I'll say it: If you're neck sizing only, or using some wonky combination of neck-size and body-size dies separately, or a Lee collet die for anything, you're doing it wrong... stop that shit lol. If you're not already FL sizing and bumping the shoulder back .002 every time, a mandrel probably won't do shit until you get that together.
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I used that exact setup for years, a Redding body die and a Lee collet die. I chucked the mandrel in a drill and used sandpaper to reduce it to the size I wanted and it worked fine.
Lee sell undersized mandrels if you do need to go smaller due to spring back or similar. They are 0.004" under instead of the usual 0.002".
Lee Precision, Inc.. Undersize Mandrels
Cartridges .002 Undersize Mandrel 243 Winchester 6mm Remington Mag 90007 6.5x55 260 Remington 6.
My current plan is (a) FL sizing with a forster die, then (b) 21century mandrel expander die neck sizing.
Does anyone consider such process wrong?
Does anyone consider such process wrong?
The best way I've heard it stated when using a Redding S die and mandrel die is, "the die/bushing sets the neck tension, the mandrel uniforms the neck tension".
The mandrel size will be the primary determining factor in neck tension. If you size down with a bushing to, say, .004" under, and then use a mandrel that's .002" under to expand it back out, you will get a different neck tension than if you use a mandrel that only .001" under.
Brass spring back will differ slightly based on bushing size, but the mandrel still drives the whole thing.
Hornady match grade dies FL 6.5CM with 190 bushing bump .002 and 21st century 6.5 black nitride mandrel. Dip the case necks in Imperial graphite before mandrel nice little layer left for the bullet to slide in with.
Side note, if you want baller low SD's you should anneal before every sizing.
Side note, if you want baller low SD's you should anneal before every sizing.
You're right on... with the exception of Hornady dies
I just got the nitride mandrel a couple months ago and it is much nicer than the standard stainless. I also use graphite. I have an arbor press with a force gauge and 9 out of 10 rounds seat within 10 lbs using this method.
Actually, if the Hornady is working for you, then stick with it. My experience with Hornady:
- When I was shooting 300 WM, Hornady dies worked perfectly fine.
- When I rechambered/barreled to 300 PRC, I was getting very inconsistent bump back with the Hornady die. I ended up ordering a custom Whidden and still use it.
- When I got my new 300 PRC, I played around with both dies. It turns out my new chamber is slightly smaller than my last (same reamer, different CNC) and when I sized my old brass with the Hornady, it wouldn't even chamber. I did a bunch of measuring, and I found that the Hornady die was about .0005 above Saami, and spring back took it to a full .001 above Saami (.533").
The chamber is super tight in the Ruger, 3x fired Peterson brass is 1.560 with Hornady comparator so I bump to 1.558 which oddly is the size the brass show up at. 
I just sit behind the thing and smack stuff way out there, the weapon does the hard part.
I just sit behind the thing and smack stuff way out there, the weapon does the hard part.IMO, sizing brass down and then using a mandrel to open it back up is unnecessarily working the brass. yes, the mandrel can be used as stated, but there is no need to begin with such an undersized bushing.
You're right. That was as an example only. I use the bushing that corresponds with the smallest neck thickness. That means that the mandrel does minimal work on those pieces, and more with the thicker necks. With a mandrel you want to have at least some push back with each piece.
Mandrel but dont trust it alone. Some brass will spring back more/less than others.
Get a few mandrel diameters and then also get the neck tension guage that you can slide into the neck to see where your combo of resizing the neck+using the mandrel actually leaves you and adjust from there.
Get a few mandrel diameters and then also get the neck tension guage that you can slide into the neck to see where your combo of resizing the neck+using the mandrel actually leaves you and adjust from there.
Case Mouth and Neck Tension Gage 224 / 308 / 310
Case mouth gauge or gage for determining neck tension of 223, 5.56, 308, 30/06, etc.
ballistictools.com
Sorry for the noob question but are you saying that annealing could cause a case head separation?
I’m not really sure I understand this.
Annealing will do nothing for case head separation as a result of too much shoulder set back. The two are not connected.
I think that’s what he’s trying to say. That if you anneal every time, you have a greater chance of case head separation than you do of over working the neck/shoulder.
Yeah, that’s the part I don’t understand.
How does softening the neck and shoulder have any effect on a failure at the base?
Edit: I think I see (rather the only thing I can reason) what is being meant...
Annealing will not lead to case head separations. But it will keep the necks in check long enough to allow for case head separation to become the leading cause of case failure down the road instead of premature split necks?
If that’s the case that originally comment is a bit misleading depending on the inflections it’s read with.
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