I’m having problems getting my bullets to repeat seating depth bullet to bullet in my reloading sessions. Sometimes the difference is as much as .005. I’m using a Forster Ultra micrometer, set up by their instructions and locked by the locking ring. Any suggestions will be appreciated.

Your bullet seating stem has a certain inner diameter of the lips of the recess which bear against the bullet's ogive at wherever the ogive's diameter matches that of the seating stem. If the bullets are inconsistent in the ogive, then seating depth will vary accordingly.

Yess I do...

Bullets AREN'T all that uniform in OAL OR OJIVE LENGTH.

If you have a seater that uses the bullet OAL and the bullets aren't uniform in length you will ALWAYS have a variation in length...I've measured hollow points that had 0.025" variation in OAL and bullets with squashed lead tips CAN'T BE MEASURED ACCURATELY

Bullets with variations in ojive measurements CAN'T be measured OR seated accurately either.

My solution has been to use the ojive measurement as most seaters use a point somewhere along the ojive with a hollow seater stem to seat by and MEASURE EVERY BULLET IN THE BOX separating by 0.005" for hunting/varminting and 0.002" when I was bench resting. Today's bullets a usually very uniform with less than 5% outliers, over/under the target number.

0.005" isn't much to worry about unless you are long range targeting/hunting, then measure/separate bu the smallest amount you can ACTUALLY measure. Your measuring tools have to be as accurate as the quantity you want to measure and you HAVE TO measure at the same point on the ojive, so check out your equipment, do what's needed to accommodate and begin again.

You also have to think about what it is you are measuring and why. 0.005" don't mean squat if your cases have that much variation in neck walls or 5 gr of H2O weight variation...your barrel looks like a snake when you look down it, your scope cross hairs flop around and your stock is just a hunk of plastic found at the dump.

Your rifle/reloading procedures/scope/etc is a system and you have to work through each one, optimize it individually,THEN optimize the whole shebang as a unit...and while you're at it "learn how to shoot" and "trigger control".

One step at a time...and there are many much better forums to go to for "benchrest/long range" type of advice...this is NOT a new question and the real answer lies in doing a lot of research and thinking beyond the "usual" envelope.

Good Hunting

Something you might check. Sometimes the contact ring around the ogive on the seater stem happens to match the angle of the ogive on the bullet such that when they come in contact during the seating process they stick together causing the bullet to be slightly pulled on the down stroke of the ram leading to inconsistent OAL. If this is the problem it can be solved by polishing the inside of the seater stem a bit.
I agree however that .005 difference won't make a difference unless you can't get them in the magazine or they are contacting the lands.

Let me summarize what they said;
!. It is normal. (.005)
2. You can't fix it.
3. It don't matter.

In my experience, my OAL (measured to the ogive using a comparator tool) is almost always within .001. I don't measure the cartridge OAL, but if I was getting .005 difference to the ogive, I would not be terribly happy. On the other hand, a really accurate rifle isn't that fussy and if it isn't accurate in the first place, who cares?

I have noticed the same issue as Blacktailer, esp if the neck tension is not tight (I have one rifle in particular that shoots well with very little neck tension).

AnotherAZW has it right.

Measure CBTO and pay close attention to case neck tension.

"That is all I have to say"
Zeke

Thanks everyone for the input. Got to thinking about uniformity of the bullets so I measured them— using same comparator and same micrometer I used when checking seating depth. They were very consistent and pretty much the same length from base of bullet to ogive. So bullet uniformity probably not the problem. Took my Forster seating die off the press and started over. Put die on, adjusted it according to instructions and loaded up some Barnes 130 gr ttsx bullets. They did fine, some maybe .001 to .002 off, but a little maneuvering of the case in the caliper would close the gap enough not to worry about. Might be something to the suggestion that the seater might be pulling on the bullet on the downstroke. At any rate I feel better about my equipment. Thanks to all— Bill

quote:

Originally posted by dpcd:
Let me summarize what they said;
!. It is normal. (.005)
2. You can't fix it.
3. It don't matter.

Exactly!

quote:

Originally posted by Saeed:

quote:

Originally posted by dpcd:
Let me summarize what they said;
!. It is normal. (.005)
2. You can't fix it.
3. It don't matter.

Exactly!

I second the Exactly!

https://www.youtube.com/watch?v=RDoJWZXQMjg

Since I started using this tool 10 years ago, (for both Partial FL sizing cases and seating bullets) , I have had no trouble with chambering ammo or getting exactly the same bullet seating depth every single time.

The most useful reloading tool I have acquired after i got the kit set 25 years ago.

quote:

Originally posted by Nakihunter:
https://www.youtube.com/watch?v=RDoJWZXQMjg

Since I started using this tool 10 years ago, (for both Partial FL sizing cases and seating bullets) , I have had no trouble with chambering ammo or getting exactly the same bullet seating depth every single time.

The most useful reloading tool I have acquired after i got the kit set 25 years ago.

So it looks like one needs to get a seater plug that contacts the bullet somewhere on the ogive and never touches the bullet tip.

Seems to me I remember from LONG AGO that at least one diemaker would offer custom seater plugs if you sent 3 bullets with your request. Makes sense if you shoot mostly one type of bullet. Would also seem that if you use a micrometer seating die that you'd want an appropriate plug.