Inconsistent cbto

[Aviator]

I’ve seen the same thing with Nosler Accubond’s

 

[wapitibob]

I quit measuring to the ogive on TTSX's, case head to bullet tip is all I do now. Groups never changed.

 

[ID_Matt]

The last boxes I checked, Nosler was WAY more consistent than the Bergers were.

That seems odd to me. Bergers have always blown everything else out of the water in terms of consistency and accuracy that I have used. Wonder why more bench rest guys don't use Nosler....

 

[mvrk28]

That seems odd to me. Bergers have always blown everything else out of the water in terms of consistency and accuracy that I have used. Wonder why more bench rest guys don't use Nosler....

I agree. I’m not shocked to hear Hornady having some issues (good marketing, crap product IMO) but I’m calling bullshit on Berger not being consistent. I weigh and measure bullets for sorting before loading and it can quite often be an unnecessary task. Maybe you and I just get the only two boxes that don’t have issues but I highly doubt it.

 

[N2TRKYS]

I agree. I’m not shocked to hear Hornady having some issues (good marketing, crap product IMO) but I’m calling bullshit on Berger not being consistent. I weigh and measure bullets for sorting before loading and it can quite often be an unnecessary task. Maybe you and I just get the only two boxes that don’t have issues but I highly doubt it.

Call it what you want, but I can only speak to my experience with them.

 

[N2TRKYS]

That seems odd to me. Bergers have always blown everything else out of the water in terms of consistency and accuracy that I have used. Wonder why more bench rest guys don't use Nosler....

I can’t answer that for you. I’m just relaying my experience and what I’ve found to be true.

 

[B23]

An interesting take on things.

 

[sram9102]

Took this picture when selling some pulled bullets. All came out of the same box of 143 eldx. You can see that a few of them are shorter than the rest. I never realized it until I laid them out.

 

[Desert Dan]

I won't claim to be an expert hand loader, but I have loaded a lot of 143 ELD-Xs and a lot of 140 and 156 Bergers. .010 variance seems awfully high, even on just a few rounds. A few things come to mind...
1) Seating stem, as mentioned above. I switched to a VLD seating stem and have had no problems.
2) Neck tension. What is your brass prep procedure? Are you annealing? Are you using bushing dies? Are you cleaning your sizing dies? Sometimes excess lubricant or grime can cause weird problems that pop up when you seat your bullets.
3) How solidly is your press mounted? Something like what what you're describing makes me wonder if it is less steady than it could be, as in whatever the press is mounted to is just a little wobbly.
4) Did you set up your dies for a slight cam over? Doesn't have to be much, but a light cam over can greatly help your seating consistency.
5) Your caliper. I used to use an RCBS digital caliper and kept getting really random variances in my shoulder bump. Eventually upgraded to a Mitutoyo and the problem went away immediately.

Could be a lot of things, but odds are there's something that is set up in a way that is conducive to a lack of consistency. Not ruling out the bullets, but I would look check out any potential issues on your end first. Good luck and update if you figure it out.

 

[mvrk28]

I won't claim to be an expert hand loader, but I have loaded a lot of 143 ELD-Xs and a lot of 140 and 156 Bergers. .010 variance seems awfully high, even on just a few rounds. A few things come to mind...
1) Seating stem, as mentioned above. I switched to a VLD seating stem and have had no problems.
2) Neck tension. What is your brass prep procedure? Are you annealing? Are you using bushing dies? Are you cleaning your sizing dies? Sometimes excess lubricant or grime can cause weird problems that pop up when you seat your bullets.
3) How solidly is your press mounted? Something like what what you're describing makes me wonder if it is less steady than it could be, as in whatever the press is mounted to is just a little wobbly.
4) Did you set up your dies for a slight cam over? Doesn't have to be much, but a light cam over can greatly help your seating consistency.
5) Your caliper. I used to use an RCBS digital caliper and kept getting really random variances in my shoulder bump. Eventually upgraded to a Mitutoyo and the problem went away immediately.

Could be a lot of things, but odds are there's something that is set up in a way that is conducive to a lack of consistency. Not ruling out the bullets, but I would look check out any potential issues on your end first. Good luck and update if you figure it out.

He stated he is measuring from the base of the bullet, a little misleading with CBTO in the title. So all of this measuring is happening prior to seating. The bullet is still outside of the case. To me it sounds like plain and simple QC issues at Hornady which wouldn't surprise anybody.

 

[Desert Dan]

He stated he is measuring from the base of the bullet, a little misleading with CBTO in the title. So all of this measuring is happening prior to seating. The bullet is still outside of the case. To me it sounds like plain and simple QC issues at Hornady which wouldn't surprise anybody.

Hmmmmm base of the bullet. By that measurement, yes I would suspect variance in manufacturing.
OP, is there a reason you’re doing it that way instead of measuring the base to ogive after seating? Seems like you’re giving yourself a lot of headaches that are unnecessary. I would also argue that if your actual base to ogive is consistent to within about .002-.003” when seating, and assuming the rest of your brass prep is done properly, you will never see an appreciable difference in accuracy, ES etc. Yes, someone can jump in and argue that even that 2-3k variance can make a difference but that’s not the point. The point is if you’re able to get your CBTO to that level of consistency and you’re having accuracy issues, it is overwhelmingly likely that the problem lies somewhere else. Not trying to bombard you with info, just trying to remove some causes of worry.

 

[mvrk28]

Hmmmmm base of the bullet. By that measurement, yes I would suspect variance in manufacturing.
OP, is there a reason you’re doing it that way instead of measuring the base to ogive after seating? Seems like you’re giving yourself a lot of headaches that are unnecessary. I would also argue that if your actual base to ogive is consistent to within about .002-.003” when seating, and assuming the rest of your brass prep is done properly, you will never see an appreciable difference in accuracy, ES etc. Yes, someone can jump in and argue that even that 2-3k variance can make a difference but that’s not the point. The point is if you’re able to get your CBTO to that level of consistency and you’re having accuracy issues, it is overwhelmingly likely that the problem lies somewhere else. Not trying to bombard you with info, just trying to remove some causes of worry.

A lot of shooters will sort bullets by ogive. Not as necessary in the hunting world unless you are willing and able to take the long pokes. If you don't sort by ogive, in theory you can get an inconsistent jump measurement but it can also effect your pressures as you start to alter the amount of volume inside the case based on the location of the ogive. Again, I don't think is necessary in about 95% of hunting scenarios but I do know that a lot of shooters do it. I have done it in the past and found that the measurements with Bergers and Hammers were so consistent or within tolerance that it was not worth the time and effort.

 

[4ester]

He stated he is measuring from the base of the bullet, a little misleading with CBTO in the title. So all of this measuring is happening prior to seating. The bullet is still outside of the case. To me it sounds like plain and simple QC issues at Hornady which wouldn't surprise anybody.

What he said was he was finding his CBTO had huge variances which lead him to measuring just the bullet.


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[Willardp]

I have had the same issue with hornady 143 eldx. I have to measure each bullet to to cbto on my 6.5 prc. I have found to get the consistent measurement it can be up to .009 difference between bullets and that plays havoc with seating depth off the lands. Since I want consistency I go through the process of measuring and adjusting in my rcbs matchmaster seater die. I like the bullet as I shoot it in other calibers.

 

[manitou1]

Never had an issue like that with 140 eldms or the 208&212’s. Is all the brass sized and prepped the same? I had some variance I wasn’t crazy about and upgraded to the VLD seating stem and it helped.

This^^^.
I was struggling to get my Bergers at the same seating depth, with variances of .007".
Ordered a VLD seating stem and now I get them within .001".
The other area I would look at is shoulder bump. If shoulder bump is inconsistent, that can be the problem.

 

[Harvey_NW]

I have found to get the consistent measurement it can be up to .009 difference between bullets and that plays havoc with seating depth off the lands.

Are you using a VLD stem? If the points of contact are consistent throughout the seating operation there should be little variation in CBTO measurements, regardless of the base to ogive measurement of projectile. The only factor would be the variations in the nose profile where the seating stem makes contact.

The other area I would look at is shoulder bump. If shoulder bump is inconsistent, that can be the problem.

Shoulder bump should have zero affect on a CBTO measurement. Again, the result is an overall length between the 2 given points.

 

[manitou1]

Are you using a VLD stem? If the points of contact are consistent throughout the seating operation there should be little variation in CBTO measurements, regardless of the base to ogive measurement of projectile. The only factor would be the variations in the nose profile where the seating stem makes contact.


Shoulder bump should have zero affect on a CBTO measurement. Again, the result is an overall length between the 2 given points.

So if you bump case shoulders with a variance of .007", you don't believe that will affect the case base to ogive measurement? I had it happen.
Ex: You set your bump and the expander ball pulls the neck up when pulling it back through. Blows your shoulder bump, stretches the case length via shoulder distortion.
The reason I no longer use expander balls.

 

[Lawnboi]

So if you bump case shoulders with a variance of .007", you don't believe that will affect the case base to ogive measurement? I had it happen.
Ex: You set your bump and the expander ball pulls the neck up when pulling it back through. Blows your shoulder bump, stretches the case length via shoulder distortion.
The reason I no longer use expander balls.

The only two things In contact when seating a bullet is the bottom of the case on the shell holder and the ogive of the bullet, or nose. How would shoulder position cause any difference if the die is set to push a bullet to a certain point and no further?