Well, I found out why Barnes Bullets "like jump" ...

moxford

Well-Known Member
Joined
Feb 24, 2017
Messages
101
It is because their tooling is not accurate.

Same box, getting 4-5 thou variance on base-to-ogive numbers.

When you jump them a lot, 4-5 thou variance is lost is in the statistical noise. (5 thou on 50 thou jump is a 10% deviation, which is hard to detect. 5 thou on a 10 jump is a 50% deviation and it shows up and you notice it more.)

Are hammer bullets any better?
 
It is because their tooling is not accurate.

Same box, getting 4-5 thou variance on base-to-ogive numbers.

When you jump them a lot, 4-5 thou variance is lost is in the statistical noise. (5 thou on 50 thou jump is a 10% deviation, which is hard to detect. 5 thou on a 10 jump is a 50% deviation and it shows up and you notice it more.)

Are hammer bullets any better?
I do know that Barnes is formed by tooling and even Barnes discussed the higher cost is driven by constant tooling wear.
When bullets are machined on modern CNC equipment, cutter wear can be monitored by the machine itself, adjusting as it goes. So, I believe that forming monos has far more variation than machining on CNC.
 
It is because their tooling is not accurate.

Same box, getting 4-5 thou variance on base-to-ogive numbers.

When you jump them a lot, 4-5 thou variance is lost is in the statistical noise. (5 thou on 50 thou jump is a 10% deviation, which is hard to detect. 5 thou on a 10 jump is a 50% deviation and it shows up and you notice it more.)

Are hammer bullets any better?
deer-eats-popcorn_64.gif
 
I find deviations similar or worse with nosler and berger and sierra. The only bullets I see that are really close are the lathe cut coppers. They all seem to be about exact. Th rest of them all have variance. Thats why I scratch my head when guys do .001 or .003 seat depth adjustments with bullets I find .007 to .012 variance in out of the same box.
 
If you're measuring to the ogive when you load, and not to the tip of the bullet, variation between each bullet doesn't really matter.

I usually load 5-10 thousandths short, then measure to the ogive, adjust my micrometer seating die and make the last seating adjustment. Each round is done individually. In this way, you can make .003 adjustments and it means something. My loads all have virtually the same measurement to the ogive and I never measure the full length when loading.

If you don't adjust each load individually to compensate for the possible bullet variations then yes, it's tough to get the same base to ogive length. As Salmonhead notes, though, with lathe-cut bullets like the Hammers I think you could use one setting and load them all, given their consistency.
 
Well your statement is quite interesting. I worried about bullet length differences enough that I opened all of my Barnes bullet boxes in 338 to make sure I was getting everything I could out of my (to me custom) 338 Edge. After measuring over three boxes I got tired of the boring consistency and decided that if the gun didn't shoot, it was the nut behind the scope and had nothing to do with the bullets I was loading. The Barnes bullets that I measured, base to ogive, varied less than one one thousandth of an inch. I don't worry about the Barnes "tooling". By the way, my 338 Edge consistently shoots five shots under a .5 moa and typically will shot five shots into less than .375 if I haven't had too many cups of coffee.
 
One day I didn't have anything interesting do, so I created a task. I wanted to see how consistent Accubonds were in the bullet base to ogive measurement.

I took 200 of the 150 gr 0.308" Accubond bullets and started measuring.

Just to cut it short and not get boring, I was very surprised at how well all 200 measured up.

I had a standard deviation of 0.00066215. This was calculated by the Excel spreadsheet I was using to log all the measurements.

All measurements were made with a Mitutoyu micrometer
 
The Barnes bullets that I measured, base to ogive, varied less than one one thousandth of an inch. I don't worry about the Barnes "tooling".
Cool, you got a better lot that I did, apparently. I now have a lot of boxes I now do not trust for anything "as is," and I'm going to have to do extra work (on an expensive "premium" bullet) to hit consistency on jump.

I usually load 5-10 thousandths short, then measure to the ogive, adjust my micrometer seating die and make the last seating adjustment. Each round is done individually. In this way, you can make .003 adjustments and it means something. My loads all have virtually the same measurement to the ogive and I never measure the full length when loading.

That's then going to muck with the internal case volume as they will be seated shallower/deeper based on the bullet variance. In my case I'm already at slight compression (N570) so that will mean seating the short ones longer, or reducing the powder load. Either way, more workup. I have been chasing the last bit of squirelly-ness from my current loads, but this is going to be a bit more work yet. I had heard great things about Barnes so I bought a bunch ... sigh.

Won't be buying any more of these, for sure, if there are other options available which reduce reloading time/fiddly-ness and provide better loaded-consistency shot to shot.

Most annoying.
 

Recent Posts

Top