Manufacturing consistancy

[IRY]

Well I was loading some rounds to shoot later today and I came across something interesting. I was loading some 162gr EldX for my 7mm. I had one bullet left form a box of 100 and I had a new box of 100. I seated the lone bullet first and measured COAL and miked the ogive measurement and everything was good to go. So I seated 14 more cases from the "new" box of bullets and measured the last one. The COAL was off by .010. I miked the ogive measurement and it was good to go!? I measured both COAL and ogive and the new bullets seem to be slightly different from the old. I have a dummy round made(with the old bullets) and ran it through the press to see if anything would change, and the measurements remained the same. So the die setting remained the same through the seating process!!! I think this is very weird!!!
The two boxes of bullets are different decor, but they have the same part numbers and written description.
I guess Ill shoot them and see if they shoot the same?!

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[Greenbug]

Different lots of bullets can cause slight dimensional and weight variations. They may have changed the plastic tip insert at that time to the new heat resistant type as well...

 

[DizzyJ]

Same lot #?

The ogive reading is what you're concerned about. OAL is going to vary a lot more.

 

[jordanka16]

Ogive is the one that matters, I ignore OAL except if I need to fit them in a mag. Non tipped bullets vary quite a bit in OAL when seated to the same ogive depth.

 

[IRY]

Well I guess they slightly altered the 7mm 162 grain EldX. the box is different and so is the listed ballistic coefficient.!!

 

[DizzyJ]

Are the part numbers different?

 

[IRY]

Part numbers are the same. I believe they redesigned the bullet slightly. shorter from tip to ogive.

 

[DizzyJ]

Part numbers are the same. I believe they redesigned the bullet slightly. shorter from tip to ogive.

Gotcha. Btw, you have great respect from me regarding your choice of quality measuring instruments. That Starret in the background is not cheap, but it's of well known high quality!