Bullet variations

[whatsupdoc]

I went through a couple hundred Berger 6.5 140 hybrids and opened a new 500 box. I noticed my coal was a little longer with the new lot of bullets so I took some measurements.

140 Berger Hybrid--LOT 8466---------LOT P0301----------Variation

Coal Loaded--------2.902----------------2.913---------------- +.011
Jump Length--------0.020----------------0.020---------------- .000
Bullet Length-------1.408----------------1.398---------------- -.010
Bullet OG to base--0.678----------------0.657---------------- -.021
Bullet OG to Tip----0.730----------------0.741---------------- +.011
Bearing surface-----0.466----------------0.445---------------- -.021


Is this much variation lot to lot normal especially the bearing area?

 

[mdmp5]

If you are asking about bullet variations, just use the measurements on the bullets, not cartridge. Berger changes their BC estimations per lot or every few lots, so yes, expect to see variance

 

[Taz575]

I used a comparator to measure the ogive to base on a box of 140gr SMK and 143 ELDX in 6.5 and there was a lot of variation on this measurement! I was shocked at the differences. Now I gotta start measuring and sorting bullets!

 

[arm017]

I've moved on from Berger bullets. It's a sacred .45$ / rd cow that is out of its prime if you ask me.

What was your sample size of these numbers? I have gotten similar numbers from 110 SMKs, and my lot of 105 hyb.
Lowest variation in my testing was with hornady ELD bullets... Consistent lot to lot, affordable, available, universally tunable in all calibers I have shot them in.

DTACs were in 2nd place in terms of variations, then Berger hybrids then 110 SMKs.

 

[whatsupdoc]

The sample size was 10 each from two different lots, I never really measured the bullet bearing surface lot to lot and this really surprised me.
I expected variation but .021 in bearing surface length just seemed excessive.

 

[arm017]

The sample size was 10 each from two different lots, I never really measured the bullet bearing surface lot to lot and this really surprised me.
I expected variation but .021 in bearing surface length just seemed excessive.

yeah I agree - how did you measure it?

 

[whatsupdoc]

I used a digital caliper with 2 bullet comparators one on each jaw. Now I understand that it is not the exact length of the bearing surface but it would give you the difference between two sample bullets.