Inconsistent OAL with lee seating die

[WookieRookie]

I'm using 9 mm lee seating die, and have noticed some real inconsistencies on OAL especially with 147 gr xtp bullets. Anyone seeing this?

[Chinny33]

i have the lee carbide die set in 9mm.

I have not noticed anything in particular.

you can TRY to send it back to LEE and have them either replace it or repair it. since its a 9mm die, the options are endless to purchase another one. RCBS, Redding, Dillon, Hornady.


A possibility is that the die itself is fluctuating in depth everytime you load a new round? Check how well it is screwed in?

Try to get a lock ring attached to the die so you know it wont move. MOST dies come with a ring that is not lockable. I purchased a lock ring for every single die I own. Its worth the extra sense of security.

CHECK to make sure that you are not crimping the brass while you are seating the bullet. That can create deviations in OAL.

Also, if you are not flaring the case enough and the bullet seater is really shoving the bullet in the brass, it could be problematic with OAL among other things.


thats all i have

[Hook686]

I load 9mm 147 grain, with my Lee Carbide dies, and have not noticed any problems.

[NWPilgrim]

I also use Lee seating die for 9mm (mostly lead round nose) and have no problems with seating variance.

Most seating variance comes from tthree situations:

1) Incorrect seating stem plug for the shape of the bullet ogive/tip. Look up inside the die or remove the seating stem and seem if the end of it that contacts the bullet tip is shaped to consistently accommodate your bullet style. It may be to sharply concave or too flat, etc. Lee can probably provide an alternate seating stem shape if you tell them which bullet you are using or send them a sample.

2) For lead bullets there can be a build up of lube in the die that causes variance. Just need to scrub that out once in a while during reloading with a Q-tip or blast it with rake cleaner or Gun Scrubber.

3) Sometimes seating and crimping in the same die can lead to seating depth variance. It is worse with lead bullets but could happen with jacketed. The heavier the crimp you have applied the more exaggerated this effect. Basically, you are trying to push the bullet into the case at the same time you are crimping the case mouth around the bullet (right at the very end of the seating). The solution is to lighten up the crimp, or crimp in a separate step after seating.

[WookieRookie]

Thanks for the replies. I'm not sure how to adjust the crimp on lees seating die, so thy must be my problem. I crimp with the taper crimp die. My instructions with the dies never mention anything about crimping with the seating die.

[jepp2]

noticed some real inconsistencies on OAL

Can you define how much? (max & min experienced)

[gregjc9]

You might also check to make sure you're fully seating the primers. I found this to be the cause with my inconsistent OALs at one time.

[PA-Joe]

Too prevent crimping while using the seating die simply unscrew the die so that it does not hit the shellholder. One or two turns should do it.

[sundog]

Since you are using the taper crimp die (good product IMO), do not use any crimp with the seating die. Adjust the seating die only far enough to touch the case, and then maybe back it out a half turn. Experiment. Check OAL after seating for consistency, and again after crimping to see if something is changing. When all is well, go for it.

Another thought. I may not be the die(s). What press are you using? Presses such as Lee turrets have a little slop in them (that usually makes no difference). Unless you are loading for extremely high accuracy, competition, near max pressure, etc., a couple thou deviation on OAL one way or the other will not hurt anything. If feed and function is reliable, load'em and shoot'em.

[wncchester]

"Inconsistent OAL with lee seating die "

It's virtually impossible for a seating die, as such, to vary OAL.

The 9mm isn't a tack driver and small variations won't mean a thing to it.

[WookieRookie]

The variance seems fairly significant. One round will be my goal of 1.110, the next will be 1.150. Probably 70% will come out at 1.110, but a few are randomly larger. I'm not near high pressure loads, but I'm trying to develop a load for this bullet in my gun, and also have OCD, so I want to keep the OALs consistent. Ill try to back out the die tonight to ensure it isn't crimping at all.Napso, I'm using an OLD Lyman Spartan press. I realize it's not the best, but there is significant sentimental value.

[PA-Joe]

Make certain that you are using the correct seater stem. I think the XTPs do seat well if you are using a RN stem.

[spacecoast]

2) For lead bullets there can be a build up of lube in the die that causes variance. Just need to scrub that out once in a while during reloading with a Q-tip or blast it with rake cleaner or Gun Scrubber.

+1

One round will be my goal of 1.110, the next will be 1.150

That's a pretty large difference, merits more investigation. Mine are usually +/- .005 from round 1 to round 50 (Lee dies). I always seat and crimp in separate steps and crimp with the FCD.

[WookieRookie]

Cleaned the die but got same results. Excuse my ignorance, but I'm not sure what you mean about the seating stem. My dies didn't come with any interchangle parts or anything. It's just a one piece die. Sounds like the seating die is crimping the round. When measuring the mouth of a seated round versus a round I seated and crimped with the factory crimping die, I get same measurement. I'll back the seating die out a bit this evening and see if that works.

[Miata Mike]

On the lee website there are several good short videos that show how to set up each die. Videos are here. I don't think it would matter much which press you use (and it might), but a nice quick tutorial none the less. Here is what they say about the seating die:

Seating/Crimping die adjustment

o With an empty case in the shell holder, raise the ram to the top and turn the die in until it stops. This is where the crimp shoulder meets the case.

o Place a bullet on the empty flared case. Raise and lower the ram checking bullet seating depth.

o Rotate the adjustment knob clockwise while holding the die. Raise and lower the ram to confirm seating depth.

o Lower the ram and turn the die in one additional half turn. Raise the ram to complete the crimp depth. If using a factory carbide crimp die, omit the half turn!

[PA-Joe]

If you screw the dies apart (remove the seater screw from the main body) there is normally an internal shaft or seater plunger of some type. These come in different shapes for different styles of bullets. Sometimes one end is for round nosed bullets and the other for flat bullets. Sometimes the dies box contains the alternative plunger.

[Unclenick]

Originally Posted by Wookie Rookie

. . .One round will be my goal of 1.110, the next will be 1.150. Probably 70% will come out at 1.110, but a few are randomly larger.

Are you sure you aren't reading 1.110" then 1.115"? It's unusual for a bullet to come out 0.040" longer and not seeing a failure of the press ram to get all the way up. 0.005" difference, though, is within normal length variance for a lot of bullet noses.

The only time I recall seeing numbers that large for myself was with lead bullets in Remington cases (this is .45 ACP, not 9 mm) which were too thin at the mouth to resize enough to grip the bullet well. In that instance the air compressed when the bullet was seated was pushing them back up a little. And that was with no crimp applied by the seater.

[WookieRookie]

What's strange is, I'll do one that measures 1.110, one at 1.150, then another at 1.110. All without moving the die. I web rerun them through, with same results. The longer OAL never seats shorter without adjusting the die n

[chris in va]

I get that with the softer Federal brass. It will practically seat itself in those cases, and result in a shorter OAL than dialed in.

[dlb435]

I've had issues with using a die set with an other brand of shell holder. Sounds like something is loose or out of true with your press.

[gman3]

I have had that problem before with lee dies. It is usually caused by a very small piece of debris lodged between the seater plug and the die body which causes it to jam, or something stuck on the seater plug. Taking it apart and cleaning it real good usually solves the problem.

[engineermike]

Just a question, if you are seating and crimping at the same time doesn't the case length come into play here? If one case length is longer than the other wouldn't the longer case be crimped sooner in the seating process, digging into the bullet and not allowing the bullet to seat as far down into the case. I guess all of this would have to be done before deforming the case?

[HiPowering Along]

What reloading press are you running?

Reason I ask is I have a Dillon XL650 that until I locked down the toolhead with a kit from UniqueTek, my OAL was all over the place. If you have a Dillon press, you might want to look into one.

With the toolhead helicoil kit, it locks the toolhead to the frame, eliminating any movement. Reloads come out with very tight OAL variations.

[WookieRookie]

I'm using a Lyman Spartan. 30 years old.

[Wag]

Someone mentioned already but to reiterate,

Lock ring not tight.

Wrong seater plug in the die.

--Wag--