Variations in OAL

[MBird]

I installed a Redding Pro Series seating die on my Dillon XL750 and I'm using range brass with Blue Bullets 135gr TC. I set the OAL at 1.14 and have gotten loads from 1.136 to 1.145. Is this amount of variation acceptable? Is this due to human error or possibly the different manufactures of the brass? Any info would be appreciated.

[Farmer]

2 hours ago, MBird said:

I installed a Redding Pro Series seating die on my Dillon XL750 and I'm using range brass with Blue Bullets 135gr TC. I set the OAL at 1.14 and have gotten loads from 1.136 to 1.145. Is this amount of variation acceptable? Is this due to human error or possibly the different manufactures of the brass? Any info would be appreciated.

 

[Runswithwood1]

My brass varies quite a bit as well, I just found out what maximum OAL will plunk in my match guns and just stay under that. I've got rounds ranging from 1.162 all the way down to 1.135 and havent had a problem as of yet

[fbzero]

Most of the reloading machines themselves have some standard variation, say 0.006.  Then throw mixed range brass with it's own variations on top of that, and I'd say this is pretty normal.

[HesedTech]

11 hours ago, MBird said:

I set the OAL at 1.14 and have gotten loads from 1.136 to 1.145. Is this amount of variation acceptable? Is this due to human error or possibly the different manufactures of the brass? Any info would be appreciated.

Yes it's acceptable, as long as they all plunk in the chamber. However, there is an updated thread on this very subject. Did you search first?

 

Here's the thread and it has a "fix" for the Redding seating die:

 

 

[MadBomber]

In my humble opinion, it has a lot less to do with the brass and way more to do with the bullet itself.  First off, you are not using "match grade" bullets.  Therefore you are going to have inconsistencies with the bullets.  Are they coated?  If yes, you are likely to have variances in the thickness of the coating.

More or less coating around the ogive will lead to differences in OAL.

 

 

[IVC]

Acceptable and normal.

 

Brass and bullets both vary enough. Just measure the length of the bullet and you'll see how much variation is there. Now consider that the seating die pushes bullet off center and that the amount of coating at the tip, as well as the bullet shape vary quite a bit. 

 

There is slim to none chance to be within much less variance. 

[kevin c]

I get +/- a couple thousandths, using same head stamp brass and home cast 147 gr bullets that I put two coats of HiTek on. That’s with a SDB.

 

Of course, my casting mentor told me I’m overly pick when inspecting and culling, I use high quality molds, and my reloading technique is sort of predisposed to consistency at the (acceptable to me) cost of loading at a reduced production rate.