Expanding mandrels..... neccessary?

[338 dude]

Hey guys, I'm always looking to improve my ammo and accuracy. Currently I neck turn and run bushing dies and shoot for .002 neck tension with a .001 shoulder bump. My loaded ammo on average has .002-.003 run out. I'm looking at expanding mandrels and wondering if I could improve my ammo even more? Seems alot of guys use them with great results. What's every ones thoughts?

Yes I use themYou say you turn necks already another great advantage to using an expanding mandrel on the inside of the neck is it pushes all irregularities to the outside which then are trimmed off when you turn the neck

 

[milo-2]

I can generally average a .4 moa 5 shot. Sometimes .3s but mostly .4s. Really looking to get close to that .25 moa mark. I'm using redding type s

I am not trying to talk you out of running mandrels, it cannot hurt. Way better expanding from above than pulling up with a standard die expander ball.
But from my personal experiences, cutting runout in half never resulted in cutting group size in half.
Paying dues during load dev does that for me.

 

[rsmithsr]

I can control neck tension much better by expanding necks with a mandrel. 99% of my brass has turned necks. I fl size with a bushing and then expand to what ever neck tension I want.

 

[bigedp51]

Just buy factory ammunition, it always has less runout.

 

[keithcandler]

If you use a bushing die, check run out with and without an expander button.

If you are getting into concentricity, then start by turning necks.

 

[Deviant]

I use Mandrels a lot and like them but I find the bushing is usually the culprit for runout. I use Widden non bushing FL dies made with my desired neck size, and run out is non existent!!!

I went to FL sizing dies with the guts pulled out and then use the mandrel and I went from .003 runout to .0005 average. I use Redding dies now because my last 3 sets of Whidden FL dies are total junk.

 

[rsmithsr]

friends don't let friends use expanders .

buttons

If you use a bushing die, check run out with and without an expander button.

If you are getting into concentricity, then start by turning necks.

 

[6MM06AI]

Love this sight! Here I am still learning. The way I undersatnd this is that I should be FL sizing then use the expander mandrel to push the inconsistencies to the outside then turn the necks? Don't know why I didn't think of that before.
Thanks!

 

[6MM06AI]

Now that I think about it, when I was using the expander in the die then turning the necks I was already doing that. Was also taught to ream the necks after fire forming to cut out the inconsistancies, it worked also!

 

[Creedmoor shooter]

I'm going to go for it. I dont see a disadvantage to it. It could only help. This is why I love this site!

 

[misterc01]

I check the neck thickness and decide from there. If it is consistent, move to the next step. Not consistent, turn the neck. Then MANY steps to get to loaded round, and finally check for concentricity, and correct as necessary.

 

[Alibiiv]

I have a custom set of dies made by Hornady for the .270 Ackely Improved. I full-length resize with the expander left out of the die and use a Sinclair mandrel to resize neck diameter. I'm getting .0005 runout to no runout at all with this system. I also anneal my brass before performing any brass prep. I also use the same process of mandrel neck sizing for the 30-06 and the 35 Whelen, all with good results.

 

[Jud96]

I went to FL sizing dies with the guts pulled out and then use the mandrel and I went from .003 runout to .0005 average. I use Redding dies now because my last 3 sets of Whidden FL dies are total junk.

Do you deprime with a Decapping die?

 

[Lenwood901]

Glad this topic came up I just got the expanding mandrel and was going to test it comparing it to sizing it with my type s die see what happens