max. OAL changes w/ each pull?!

[Hiaboo]

Seating bullets last night in LC07 cases (.223) with 62gr green tips -

The OAL would be different with each shell??! One would be 2.249 then the next would be 2.250 then the next would be 2.242 then I'd get 2.250 again what gives?

I even had a few that was in the 30's (fixed those).... Even if the brass was trimmed incorrectly, the OAL should NOT change...

I don't get it. I'm using a LEE anniversary kit, w/ pacesetter dies..

On a side note, I hate the lee perfect measure and scale yuck.

 

[Walkalong]

Brass trim length has nothing to do with O.A.L., as you stated. That is not all that big of a variation you are getting. Pretty normal actually.

What is important is length from the base to the ogive which will take a special tool to measure. Stoney Point makes a good one.

 

[Mr White]

Like Walkalong said. 5 or 6 .001s isn't very much. The variations are caused by differences in the bullet tips. The Ogive lenght is what matters as that is what determines how far the bullet is from the lands.

You'll see a much smaller variation in good match bullets like AMaxes, SMKs or Bergers, but you'll still get a few .001s even with them.

 

[JonB]

I had the same issue while using Winchester 55 gr bulk packs. I'm guessing it has something to do with bullet manufacturing variances. Maybe the bulk packs come from several machines versus more expensive bullets that may come from a single machine. I figured the variance was small enough to be ignored.

 

[Hiaboo]

Alright, good call thanks guys.

 

[30Cal]

This comes up as a weekly topic. Your sizing die doesn't push on the point (which is undesirable anyhow because bullets vary).

 

[kelbro]

Some longer bullets will 'bottom out' in a seater die causing large variations in OAL. Probably not the case with the bullets that you are using but I do have to drill out seater plugs every now and then to accomodate VLDs and the like.

 

[Bullet]

Hiaboo
You might look at this -

http://www.sinclairintl.com/cgi-bin/category.cgi?category=RESDTCO&item=09-600&type=store

 

[infantrytrophy]

OAL variances

To expand on what Walkabout, 30Cal and Mr White said:

Hollow point and plastic-tipped bullets vary surprisingly in their lengths. Check it yourself - measure samples of these bullets for overall length. They vary by up to .004 or .005. I was floored by this - it was completely unexpected. This would account for your OAL variation because, as others have said, the bullet seating stem contacts the ogive, not the tip of the bullet.

 

[presspuller]

This is probably not your problem but if the die is adjusted too low and is causing a crimp that can mess up the OAL sometimes too.
But most likely its has been said and is just a variance in the bullets.