Checking projectiles between batch numbers

Routine measurements of new batches often show no change but this time they were there


Here you can see the Nosler 140g 7mm projectiles on the right have more Copper in their alloy than the newer ones on the left, no doubt softer and from a much earlier batch, we know Nosler toughened up their Ballistic Tip line and the alloy blend was one change

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Measuring with a comparitor on the verniers there is also a difference in length from the ogive to base and ogive to tip, 14 thou difference

Thats considerable and could really give you grief if you used the new batch at your old COL (cartridge overall length) or ZCL (zeroed comparitor length) settings

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So all in all a timely reminder to check your projectiles between batches, not only for our own safety, but also to make sure they go where we want them to go

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Merry Xmas all, cooler weather today -have put the lights up :)


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I changed batches when loading some 308 eld-x 178gr, coal (to tip) was 20 thou longer with the new batch without changing anything on the seating die, but length to ogive was the same.

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Originally Posted by Cigar

I changed batches when loading some 308 eld-x 178gr, coal (to tip) was 20 thou longer with the new batch without changing anything on the seating die, but length to ogive was the same.

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That’s considerable, just as well you kept an eye on everything

I had a customers 270 got nuts with Nosler Ballistic tips

He couldn't remove a loaded round from the chamber without leaving the projectile in the chamber, not a particularly handy feature for a hunting rifle in the field :XD:

I got it all back & it turned out there was over 45 thou difference in loaded length between batches of Ballistic tips :wtfsmilie:

Shortened them & it was GTG from there, I always check now, BTs are the worse I've found so far:(

I still check lot to lot but don't find Bergers for example to be too inconsistant. Hornady a little less so. However, Berger could now drop the ball now they are owned by Nammo and are having trouble (or were recently) keeping their production up to demand.

Around 20 years ago Sierra 6mm 107 MKs were showing up with not just big lot to lot differences but big differences within one box. Some boxes I sorted into 3 distinct batches (ogive to base). Thankfully they picked up their game.

A product of the bigger makers running several machines side by side with dies either different to start with (unbelievable) or dies in different states of wear.
Supposedly each machine's output is kept seperate but found this hard to believe with my Sierra experience those years ago.

That's interesting.
A year or so back I went through and rechecked my loaded ammo dimensions against what I'd developed the load and had to adjust my reloading gear, specially the seating die to regain the old CBTO.
I thought it was the press wearing or something.

I can put up with the shape or even weight of the projectiles changing. Please, just call it "Ballistic Tip II " so we know. The packaging did change to include pictures of what you might shoot with it.
You should check your CBTO each new batch you reload (should). Sothis ought not to catch us out.

BUT I'm not happy to have he terminal ballistic performance altered. No way you can recaibrate or redope for that. It takes a lot of good animals to rebuild assurance that a new projectile is fit for purpose..

An interesting thread this. I admit I never bothered to check batch to batch.

As well as changing projectile dimensions, it’s worth noting that manufacturers change jacket thickness and composition too, as mentioned above. I think this is mainly down to US hunters driving them too fast in fast twist barrels then complaining when projectiles disintegrate. The result is manufacturers getting twitchy and projectiles being beefed up to the point that they fly well but terminal ballistics suffer, esp at longer ranges.