Home Forums Reloading Big Game Rifles Bullet seating consistency?

Have noticed over the last several years that some sets of dies and some types of bullets are less consistent in seating depth consistency.

Typically, when setting up for a different bullet I'll start a bit long and shorten up til I get the oal I want. measure a couple at the start and then forget it til I change bullet again.

Have been paying a bit more attention lately, and am curious as to how consistent others loads are in seating depth.

Tonight, I loaded 100 25-06 and was aiming for c.o.a.l. of 3.145. Depth to lands is 3.160 with this bullet. Of the samples I checked, oal ran from 3.140 - 3.148. One load that I accidently ran the lead tip into the bottom face of the die measured 3.130.

How does this compare to your experience?

My guess is the ogive of your bullets are not consistent. This will result in some bullets being able to advance further into the seating stem and others less so. I have in the past seen more variation than the .008" you cite. Think of the ogive contacting the seater as a datum point. Change the ogive and the datum point changes. C.O.L. doesn't tell the whole story.

Neck tension variations will cause this as will compressed loads.

Are you measuring off bullet ogives or tips?

I measure off the ogive and some bullets give me fits in trying to keep each round the same.

Which seating die and bullets give you such trouble?

It sometimes helps to take out your seating stem and polish the end where the ogive of the bullet contacts it. You can do this by lightly chucking the stem in a drill (so you don't mess up the threads) and polishing with some fine sandpaper. This keeps the bullet from sticking in the stem while seating.
I have had this happen so bad that the bullets would pull back out of the cases when the ram was lowered.

6.5X55 Lee Seater

Most bullets are fine, so I am reluctant to jump on the "Lee is crap" bandwagon.

140 Hornady SPs
129 Hornady SPs
130 TSXs
Some Ancient W-W 100 SPs
This group varies more than I'd like. They aren't terrible, but I just wanted to share my experience.

Best, John

I measure off the tip of the bullet. I possess no way to measure off the ogive.

The worst of my dies are my rcbs 25-06 set, and the worst of the bullets are the hornady 100 IL, and the sierra 117 BTSP.

Measuring off the tips isn't all that consistent. It's easy to see several thousandths round to round on the tips even when the ogives are dead nuts even.

Watch the video about the Hornady Bullet Comparator.Overall lengths used to drive me crazy.They were all over the place.This tool has really saved me many headaches.
http://www.bing.com/videos/search?q...AF9A9C92B72EACE9BC52AF9A&FORM=VRDGAR

baldhunter - do you struggle with getting repeated readings when using the tool to determine distance to lands for a given bullet? I get many different numbers and finally settle on one that seems the most representative.

Buy one of these and measure off of the ogive:

http://www.sinclairintl.com/reloadi...-style-bullet-comparators-prod83792.aspx

My Redding competition seaters and the Forster ultra seater have been really consistent for me. Compressed loads can affect it too.

Seating pressure can also influence seating depth consistency. I first noticed when I was loading the same bullets into cases prepped the same way but doing an increasing amount of powder; example 30-06 loading RL22 in sets of 3 at each powder level, 59.0, 59.5, 60.0, 60.5 etc.

When the bullet starts compressing the powder, the OAL would increase. IMO this is due to increased pressure on the linkages of the press and the seater can not seat as far.

Also happens when you have an inconsistent neck ID or inside neck surface.

IOW when a bullet is harder to seat for whatever reason, the OAL will increase slightly

Bingo. Why ask the question when you are measuring off the tip of the bullet. The seater is going to push off the same spot on the bullet which makes the OAL meaningless when measuring off the tip. The seater doesn't push on the tip of the bullet, but closer to the ogive. Just like when you check where the lands are with a dummy round. The sides of the bullet come into contact with the lands, not the tip. Some of this chit is pretty simple really. Damn sure not rocket science...