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Importance of concentric neck expander?

M60A3TTS

Silver $$ Contributor
I've been looking for a 7MM Rem Mag dies set. I bought a used RCBS set from a member here, and noticed the rod was bent, pretty badly. Started to use it anyway and after 40 rds thought better of it. Went on to other calibers for a while and came back to the 7. So I ordered a set of new RCBS dies, only to find the decapper pin and expander where bent at the junction of the thread. Back it went and ordered a Forster set, same issue. In the past 2 weeks I have ordered 2 sets of Hornady Customs, one with bent rod, one with bent tip at the thread junction, and the decapper pin bent beyond that.

Now I know many don't have a great opinion of Lee, but none of my Lee sets ( 2x30.06, 2x 308, 1 x 300WM) , have this problem,and these have been heavily used . I'm I seeing a none issue, or have I just, seemingly, been unlucky??
 
I won’t even use dies with expander buttons at this point. I just mandrel in a completely separate step.

I’ve only bought L.E. Wilson and the BC Micron dies the last few years and neither of those even include buttons. It’s basically an undersized pilot that will take some dents out of the necks depending on how severe, but the expectation is that you set neck tension separately.

If you’re talking about the pin itself it doesn’t so much matter as long as it fits through the flash hole.
 
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I've been looking for a 7MM Rem Mag dies set. I bought a used RCBS set from a member here, and noticed the rod was bent, pretty badly. Started to use it anyway and after 40 rds thought better of it. Went on to other calibers for a while and came back to the 7. So I ordered a set of new RCBS dies, only to find the decapper pin and expander where bent at the junction of the thread. Back it went and ordered a Forster set, same issue. In the past 2 weeks I have ordered 2 sets of Hornady Customs, one with bent rod, one with bent tip at the thread junction, and the decapper pin bent beyond that.

Now I know many don't have a great opinion of Lee, but none of my Lee sets ( 2x30.06, 2x 308, 1 x 300WM) , have this problem,and these have been heavily used . I'm I seeing a none issue, or have I just, seemingly, been unlucky??
Never used an expander ball. Don't like the idea of a ball hanging on a long rod suspended by sloppy threads1.5" inches from the ball. Some top shooters use a mandrel. For years now I just use a bushing die. Good enough to shoot around .350" with good bullets and a good barrel.
 
A "Do it all" tool, does nothing well.

Advice taken. Sending dies back, already boxed and tagged. Just have to decide on bushing or mandrel.

Or?

You need something to reduce the diameter of the neck, a bushing die gives you selectable control but misses sizing a portion of the case at the base of the neck. A custom die does not have that deficiency. An off the shelf die probably oversizes the neck.

A mandrel will bump the ID of the neck and ensure it is straight. Otherwise you are using the bullet as a mandrel.
 
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Depends how many cartridges you run in each calibre, orhow many calibres you own, but, one set of mandrels is a one time purchase per calibre, not per cartridge. Once you use them, you'll probably ask yourself why you didn't do that a long time ago, too, even though it's an extra step over using the buttons in the die.
 
A "Do it all" tool, does nothing well.



Or?

You need something to reduce the diameter of the neck, a bushing die gives you selectable control but misses sizing a portion of the case at the base of the neck. A custom die does not have that deficiency. An off the shelf die probably oversizes the neck.

A mandrel will bump the ID of the neck and ensure it is straight. Otherwise you are using the bullet as a mandrel.
EXACTLY!!!!
 
Depends how many cartridges you run in each calibre, orhow many calibres you own, but, one set of mandrels is a one time purchase per calibre, not per cartridge. Once you use them, you'll probably ask yourself why you didn't do that a long time ago, too, even though it's an extra step over using the buttons in the die.
Very true. Most of the shooters now are always on the CLOCK. Shoot fast and reload faster, good enough for 2 moa targets. They want short cuts, not more steps. I love building a high quality repeatable round and prefer to take any step to do it. I have steps in my process that many shake their heads at....but that's what it takes to hit softballs and milk jugs at 1000 yards.... Small smile here.
 
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I pull the expander buttons and size the case in the dies then run them through an expander mandrel. Neck concentricity is VERY important to building accurate ammo.
Contrary to popular belief, neck concentricity has very little correlation to building accurate ammo. Don’t believe me, load your best 10 pieces of ammo in terms of neck runout and shoot them against your 10 pieces of the worst neck runout your die makes using the exact same reloading process. Don’t believe what people tell you unless you’ve tested it for yourself. I’ve tested this at least 4 separate occasions.
Dave
 
Contrary to popular belief, neck concentricity has very little correlation to building accurate ammo. Don’t believe me, load your best 10 pieces of ammo in terms of neck runout and shoot them against your 10 pieces of the worst neck runout your die makes using the exact same reloading process. Don’t believe what people tell you unless you’ve tested it for yourself. I’ve tested this at least 4 separate occasions.
Dave
I have tested it with my 6br norma and 300 prc which is why I'm saying its important. especially at distance past a 1000 yards which is typically what I shoot. I can look at the target and you can see how the bullet was flying by its imprint left on the target. I've also taken loaded ammunition with .004 runout and shot it against ammunition with less than .001 runout at 1500 yards, The ammo with .004 runout had 3.8 moa more drop than the ammo with less runout due to it losing its dynamic stability from imperfect flight.
 
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I have tested it with my 6br norma and 300 prc which is why I'm saying its important. especially at distance past a 1000 yards which is typically what I shoot. I can look at the target and you can see how the bullet was flying by its imprint left on the target. I've also taken loaded ammunition with .004 runout and shot it against ammunition with less than .001 runout at 1500 yards, The ammo with .004 runout had 3.8 moa more drop than the ammo with less runout due to it losing its dynamic stability from imperfect flight.
Were you using wind flags? :p
 

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