Bushing Dies + Mandrel?

[Mule3006Elk]

Those of you that have been down this rabbit hole school me. I have Lapua brass and do all the standard brass prep,

I use Redding bushing dies and I removed the expander ball from the get go. I set neck tension to 0.002. Is there any benefit if I set neck tension to 0.003 or 0.004 then use a mandrel 0.002 under caliber? I don't neck turn FWIW.

I hunt and work up hunting loads specifically. 300 WM, 30-06, all sub MOA. The chambers are not excessively tight as these are not custom builds so moving some brass to the outside of neck is not an issue. I'm working on a new rifle (6.5 PRC) but still accumulating all the components and reloading essentials.

I love to tinker with reloading and the extra step is not a concern plus minimal expense for the mandrel and die. BUT...if it's not helpful then I won't waste my time.

 

[SDHNTR]

Buy an upgraded carbide expander ball from Redding and put it back it the die. I’ve been down the rabbit hole with expander mandrels, no expander at all, regular expander ball, standard non-bushing dies, the whole bit. In fact, this was just covered in another thread everyone will have a different answer to this. All things considered, for a hunter, and given the best balance of precision and ease/speed of reloading, I have arrived at Reading type S, FL die, with Redding gold or SAC bushings, and a carbide expander ball installed. Hand depriming.

 

[BBob]

Is there any benefit if I set neck tension to 0.003 or 0.004 then use a mandrel 0.002 under caliber? I don't neck turn FWIW.

For a generic field rifle I doubt you can shoot the difference or even see a difference between the two methods but someone will be along shortly to tell you they get a benefit. I’ve said it before and I’ll say it again most of this BR stuff people do for field rifles is a waste of time and $$$ but hey try it and see

 

[Mule3006Elk]

Buy an upgraded carbide expander ball from Redding and put it back it the die. I’ve been down the rabbit hole with expander mandrels, no expander at all, regular expander ball, standard non-bushing dies, the whole bit. In fact, this was just covered in another thread everyone will have a different answer to this. All things considered, for a hunter, and given the best balance of precision and ease/speed of reloading, I have arrived at Reading type S, FL, die, with Redding gold or SAC bushings, and a carbide expander ball installed. Hand depriming.

Using the carbide expander ball, how much neck tension do you set with the bushings and how much does the expander ball open it up?

Update: Online a few references state the expander ball is 0.002 under bullet diameter. With your bushings are going 0.003 or 0.004 neck tension?

 

[Mule3006Elk]

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For a generic field rifle I doubt you can shoot the difference or even see a difference between the two methods but someone will be along shortly to tell you they get a benefit. I’ve said it before and I’ll say it again most of this BR stuff people do for field rifles is a waste of time and $$$ but hey try it and see

Probably correct. I do a lot of brass prep and I can't, usually, tell the difference.

 

[waspocrew]

Probably not going to be a huge difference. I have a mix of bushing dies, a few expander mandrels, and just normal FL dies. The only reason I picked up some mandrels was due to some excessively tight Peterson and Alpha brass.

 

[SDHNTR]

Using the carbide expander ball, how much neck tension do you set with the bushings and how much does the expander ball open it up?

Update: Online a few references state the expander ball is 0.002 under bullet diameter. With your bushings are going 0.003 or 0.004 neck tension?

.002. Springback can vary, as can neck wall thickness so it might take some experimentation with different bushing numbers to get the right interference fit. It’s also a “feel” thing. I want a bushing that sizes down just enough so that when I pull the expander ball back out the neck, I can just barely feel a smooth glide of the ball through the interior. If it’s grabbing, you’re sizing the neck down way too much.

 

[Backcast88]

I am new the bushing die and mandrel game so take it for what its worth. Sometimes you just gotta play with combos to get the desired results. I tend to neck down .004 with my bushing and then run either a 262 or 263 mandrel through it depending on the brass and bullet combo.

I have found with my fouler/sighter rounds loaded with hornady brass, I use a SAC 288 bushing and a 262 mandrel. It produces good accuracy with H4831SC and Hornady 140 BTHP.


But when I go to my Lapua brass which is much thicker, I go with a SAC 290 bushing and a 263 mandrel. The 262 mandrel is too much neck tension and accuracy suffers.

 

[SDHNTR]

Also, fwiw, as a hunter the only neck tension I really care about is just enough to keep the bullets from seating deeper in the mag under recoil.

 

[Axlrod]

I have tested most every resizing process out there. On custom hunting rifles, custom target rifles, and off the shelf hunting rifles.

The most consistent results were from using bushings only, and size the brass till the striped bolt will just close.
On mostly custom built guns in 284 Shehane, 284 Win, 28 Nos, 30 Nos, and 338 LP. I have had the best results on paper at 600-800 yards, with neck tension .004 to .005. A 243 AI and a 220 Swift liked .002 NT the best. I haven't experimented enough on factory guns to say if it would be beneficial or not.
I try 3 bushings at least. If you don't have the time/resources/desire etc. I would shoot for .003 NT. Good luck!

 

[Dos XX]

Why not just use a bushing, no mandrel, no expander ball?

 

[wind gypsy]

Why not just use a bushing, no mandrel, no expander ball?

Main negative talking point in that case is varying interference fit or neck tension because the inconsistent neck thickness dimenision is pushed to the inside of the neck vs the outside when the last sizing stem is a mandrel or expander ball.

Using quality brass with generally consistent necks, I didn’t find a notable difference in results between bushing die only no expanding, bushing die with expander ball, and bushing then mandrel to expand.

 

[SDHNTR]

Why not just use a bushing, no mandrel, no expander ball?

You’re pushing neck inconsistency to the inside, with nothing to smooth it out. I know lots of people do just that. I used to also, and with good brass I didn’t notice much downside, but in theory you could also have wider spreads and potential flyers. It’s just as easy to run a properly fitted carbide expander ball back out the neck and reduce or remove those chances. It doesn’t require any extra steps so I see no downside.

 

[SDHNTR]

Main negative talking point in that case is varying interference fit or neck tension because the inconsistent neck thickness dimenision is pushed to the inside of the neck vs the outside when the last sizing stem is a mandrel or expander ball.

Using quality brass with generally consistent necks, I didn’t find a notable difference in results between bushing die only no expanding, bushing die with expander ball, and bushing for then mandrel to expand.

Wow, we were writing essentially the same thing at the same time. Great minds…

 

[SloppyJ]

On my last two die sets I've been using the RCBS matchmaster FL sets with the seating die that has a window. Super cool seating die but that's for another thread.

I've been using the expander ball that comes with the set instead of taking it out. All of this has been on new brass so that's why I've kept it in.

I set the bushing so it just barely floats in order to size as much of the neck as I can. I'm using bushings to provide between 2 and 3 thousandths of neck tension.

So far the results have been much more consistent in regards to run out and accuracy. I don't have anything else to compare it to but my new .223 barrel was putting down some of the best 10rd groups I've shot in my life. Could be a badass barrel but I'd like to think it has something to do with my switch to the new-to-me resizing dies.

This thread is perfect because I've really been trying to decide how I'm going to run the dies on subsequent sizing. I haven't used any mandrels but was thinking about trying it. With the info I just read I might just hold what I got for now. Plus, with two kiddos running around, keeping the balance of time when reloading on the efficient side is beneficial.

Does anyone make expander balls that are custom sized? That might be a neat option to test.

 

[Mule3006Elk]

Main negative talking point in that case is varying interference fit or neck tension because the inconsistent neck thickness dimenision is pushed to the inside of the neck vs the outside when the last sizing stem is a mandrel or expander ball.

Using quality brass with generally consistent necks, I didn’t find a notable difference in results between bushing die only no expanding, bushing die with expander ball, and bushing then mandrel to expand.

Concluding statement speaks volumes. I'm using Lapua brass. I might be able to skip a few steps and save some cash. Did you test bushing dies, no expanding, with different neck tension? Just curious. Thanks