Same Bullet Different Length

L

LiveTheHunt

New member
Need a little advice. Around two weeks ago I ordered 100ct box of Nosler 6mm 70gr Ballistic Tips. They measure .918-.919 Developed a load and ordered a 250ct box today it arrived and noticed they looked shorter and they were. They measure .904-.905. Contacted Midway by email this evening so not sure what they will say. Shoot em or not?
Grain weight is fine they all match. I know they will seat fine and function fine. But what about my pattern? Is this a typical problem? Newbie to reloading.
Thanks in advance.
 
I would make up some test loads of about 1/2 gr above (unless already max), at, and below your established load. Make 5 of each load and shoot & compare POI and group size. Hopefully nothing will change or only the POI will change and you can just adjust the sighting. I would not load up a bunch until you see how they do. The + & - 1/2gr tweaks would be in case accuracy went to [beeep] and a slight powder change was needed. If all 3 loads are less accurate then you will need to start over with load development because it is a different bullet in spite of its similar weight. The ogive could be different and now you could be closer or farther away from the riflings.

If you don't want to bother with test loads then see if you can get prepaid shipping back and try to get exactly what you used before.
 
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Well I’m at 41.5 gr Varget on em now. Think max was 41.7? May have read a different load that said it was ok to go more... have to check.
I’ve got around 65 loaded up so I guess I’ll wait to see what Midway says and go from there. Ideally it would be nice if they would open the box and take a measurement before we did all this shipping back and forth. Curious to why they changed them...
It was noticeable as soon as I opened the box.
 
I would just load a few that have the same Ogive length and see if they shoot the same. I always load a given distance off of the rifling and let the OAL be what it is as long as they load in the magazine properly.
 
Welcome to the real world!

bullet jackets can vary a tad in length, but it it normal for there to be different ogive lengths going from lot to lot, and this will mean that you will have to adjust your seater die.
 
It’s been a learning curve for sure!! I have 5 rounds loaded up within 1-2 thousandth of the original length measured from the ogive with a comparator. See what they do I guess.
 
Many years ago I contacted Hornady to discuss this very thing. I had noticed what I thought was "significant" differences in bullet lengths within same lot numbers. I was surprised by what they told me as what was "acceptable". You have to remember that bullets are manufactured within a set of specifications. Those specs exist to minimize variations, but anytime a process involves tooling, it causes wear. As it tooling wears, it affects those tolerances.

Don't overthink it. Like others have said, just roll with your BTO measurement. It will remain "constant" for different lot numbers of bullets. The only time I am concerned with COAL is where magazine constraints come into play.
 
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