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9mm bullet runout


FriarWhently

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Hey guys, I'm having some difficulty reloading 9mm and I'm about at my wits end. The issue is cartridge runout - in about 10-25% of my rounds, if you lay the cartridge on its side and roll it, the tip of the bullet wobbles a little bit. Essentially some of my bullets are seating slightly crooked.

Brass - mixed, 1-3x fired; this problem happens with equal frequency regardless of the headstamp.

Bullets - Zero 115gr FMJ, 1.125 COAL

Dies - Lee sizing die, Lyman M expander die, Hornady seating die, Lee FCD. The problem was worse before I got the M die and the seating die, but I can't get 100% perfectly alligned bullets. The problem is present regardless of whether or not I use the FCD

Press - Lee hand press (the Nutcracker); I live in a small apartment with no room for a mounted press, unfortunately.

I've tried expanding more and less, to no avail. More expansion actually worsens the problem, as there's more play between the bullet and the case. When seating, I start the bullet in about half-way, lower the press ram and turn the bullet a bit, then seat the rest of the way. This has helped, but again not 100%. I've tried the Lee U die and undersized the cases but this makes it worse. I've even gone so far as to pull apart a crooked round, chuck the bullet in a drill just to make sure the bullet itself isn't a defective, crooked bullet, but the bullets are all fine.

Thinking the bullets would seat straighter with a longer bullet, I've tried some Zero 124gr FMJ. These seat straighter than the 115gr, but about 10% of those are still slightly crooked.

All cartridges chamber and fire just fine, but I'm trying to make the most accurate rounds I can, which means having the straightest rounds possible. Short of spending a bunch of money on a Redding Competition Seater die or somehow mounting a better press to my wall or something, I'm at a loss of what to do. Any ideas?

Edited by FriarWhently
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My thoughts as well.

If the seating stem doesn't fit the bullet, you could have trouble. The contact with the stem should have the bullet push evenly and directly into the case. If, say, you have a round nosed bullet that can move around in the interior of a stem designed for conical bullets, it might slip/tilt.

Some of this is avoided in a mounted press where the case is upright with the bullet sitting on top before contact with the stem. Gravity is helping you here - if the bullet stays upright while sitting in the case, direct contact from above from the flat meplat section of the stem might be enough to push the bullet straight down. Your hand held press may allow more play/tilt.

If you are using a bullet with a rounded ogive, check to see if the bullet is contacting the stem at its tip/meplat or on the ogive/shoulder. My experience is that the last is better.

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The seating stem I'm using is conical and is contacting the ogive as far as I can tell. The best results I've been able to get have been with an amount of flare/expansion that the case is barely open enough to accept the bullet...I actually have to use a little bit of force to place the bullet on the case. It seems like the tight initial fit may increase the chance of a crooked seating, but I actually get more crookedness if the bullet has more play initially with the case.

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DWFAN: that's the kicker. I've only recently started reloading 9mm (reloaded lots of 38 with zero issues) and have been working up a load. I'm finally at the point where I can make a really large batch of rounds, which will give me a decent amount of crooked ones to really test the accuracy of. Up to this point I've only had 2-5 of these crooked rounds per range trip which, IMO, aren't enough to really make a comparison with. Now I have about 20-25 of them. It may turn out that I can't tell any difference between the crooked ones and the straight ones, but it just seems that they would HAVE to have SOME effect on accuracy. We'll see for sure this weekend...

I appreciate all the help so far guys.

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I see you have stated hand press. Do you in fact mean the hand press or a bench press? Is it possible that when you get a crooked one you have the hand press crooked and the bullet does not get seated correctly? Look after seating and see if they are crooked or if after the fcd. I saw where the fcd is not really necessary for 9mm unless you have severe bulging. Definitely start inspecting each process! I would also make sure you only flare just enough for the bullet to barely sit on the case not in the case!

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I had this problem when using either the RCBS or Dillion bullet seater and not placing the bullet straight on the case before seating.

The plug would not align the bullet perfectly before seating it.

I fixed the problem by buying a competition/micrometer bullet seater. This die aligns the bullet before pushing it into the case.

It is a bit on the pricy side just to have minimal runout, but you have the easily adjustable bullet seating depth.

But like DWFAN implies, does it matter for your accuracy requirement?

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Try using a box of Hornady 9mm bullets to match your seating die. My experience with Hornady has been that any one product seems designed to complement another, but not necessarily anything else on the market. The seating die stem is probably cut to the contour of Hornadys 9mm bullets, which may not match Zeros contour. This may not be the problem, but it is something I've noticed with Hornady rifle bullets and dies. I get less runout if they match.

Yes, I know this sounds silly.

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