9MM OAL Question

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littlebob3

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I'm loading on a LEE Load Master with a Redding Competition Seater Die 9mm.
After making 30 to 40 bullets I check the OAL with a digital micrometer and I get:
1.1490
1.1505
1.1520
1.1540
1.1560

Am I doing something wrong… should it very the much?

Thanks for any input.
 
is it progressively getting a smaller OAL? If so I would keep for build up on the seating die but that's only if you tumble lube your bullets.
 
You should be able to get at least around a .005 swing from low to high if the seater tip fits the bullet well.
 
It is just some numbers... after a hundred i will get:
10 that are 1.1490
5 that are 1.1505
20 that are 1.1520
10 that are 1.1540
3 that are 1.1560

And so-on
 
((.005 swing from low to high))

That is what i was thinking...
I'm using Berry's 115 gr

The die is new and has been cleaned

Not sure what check now.
 
Are you running the ram all the way to the top? Are you sizing while seating in a turret or progressive?
 
progressive, just did a test with only 4 brass and 4 bullet Nothing elce in the press and again...
1 @ 1.1510
1 @ 1.1490
1 @ 1.1230

May it is the bullet... I will do another check with some other bullet.
 
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Littlebob,

As you suggested, check your bullets. I had the same problem with Precision Delta bullets. The bullet shape was not consistent at all, therefore the point on the bullet that contacted the seating die plug varied, thus inconsistent OAL.
 
Well crap… not sure the Hornady Bullets 9mm (355 Diameter) 147 Grain Full Metal Jacket Round Nose… were better…

Change the setting loaded the Hornady Bullets and Got a reading of:
1.1085
1.1140
1.1125
1.1185

Thanks for all the input.
 
My seating plug for my 550B has one end for RN and reverses for FP bullets. Might make a difference if you have it set for FP and are using RN bullets.
 
Your OAL "extreme spread" should be no more than +/- a few thousandths--even .005 could be ok if they're not "hot loads" or "starting loads".

Those last numbers are too big of a spread. You're doing something wrong or "less than right".
 
► All presses will result in some variation in length.

► First-time reloaders always have high variations that seems to settle down after the first week. It has to do with your arm movements. Try to be smooth and steady with your action. Lubing the cases and the press will help.

► Watch THIS GUY. He moves at exactly the right speed and tempo for perfect ammo.

► With auto cartridges you can simply send the long ones back through the seating stage with no harm done.

Hope this helps!
 
Lee seater plug will squish hollowpoints if you try to crimp them at the same time. Take a close look at the mouth of the seated bullet and compare to a virgin one.

As for the Berry's, all plated bullets are dead soft lead, and they deform quite easily. There are ways to make a custom seater plug with epoxy, or with a drill/lathe. You might wanna give it a try if you find a bullet you like. Or send some to LEE, and they'll sell you a custom seater plug. This can make a huge difference in your OAL consistency.
 
I think that having +/_ .005 isn't a big deal in loading pistol cartidges, especially with some bullet types and profies. Remember that many the seating stems in dies will locate on the ogive of the bullet and not the actual nose. If you have ANY difference there, it will show up in OAL. This is especially true with cast bullets that show a mold seam line.
 
Not sure what you are targeting for the OAL but I use berry's also and my target OAL is 1.130 and I do see some variation in the length. Usually I am within about .002 but sometimes I can see about .005. It doesen't bother me much though as I am not near max charge.

For my .40S&W I do seat and crimp in separate dies and have a much more consistent OAL, but I don't do this in my 9mm, and as was stated earlier the bullet variation will contribute to this as well as the seating stem. I use Hornady dies for all my reloading, good luck
 
a spread of about 0.005" won't make any difference. If you have any more than that, then something is out of whack.
 
Took the Redding Competition Seater Die apart, cleaned and reset as suggested by Redding… Now I get + - .001 to + - .002

Very happy with Redding. :)

Again many thanks to all.
 
Your going to see variations of .005". Some of it just bullet inconsistencies, and some may be coming from how you work the press. But over all, if you aren't into the lands .005" will not be enough to cause problems.
 
Looks fine to me, I dont see a problem with the lengths in your OP. I get that on all my loads too, even mid priced hunting bullets. My guess is it has to do with slightly different ogivs...
 
Well, this is quite a surprise to me. When I seat their HB-FP bullets with a RN stem, I can SEE the tip get squished. There's a nice cone shape coming up from the shoulder... then there's a second shoulder/bend where the Lee standard 9mm seater plug has reshaped/narrowed the top third of the tip. My OAL is all over the map. The Speer and R-P OAL's are way shorter, with little or no deformation. The thicker cases get the funny looking squished bullets with a much longer OAL. Making a custom seater plug fixed the problem.

I got so excited by this discovery, I was determined to make custom seater plugs for all my bullets. This is how I discovered that when I take a MBC .357 Action! 18BHN SWC bullet (which has a true, near razor sharp-edged FP compared to the Berry's rounded edge) and seat it with a RN plug, there's zero deformation even on this thin edge. OAL is spot on. No custom seater needed. (Of course, I made one, anyway). :)
 
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