Variations in neck tension of new Lapua brass

[Jelen]

I've been using Lapua brass in my 6.5x55SE for years. Recently bought a blue box, sealed and genuine.
Knowing that the Lapua necks are usually tight from the factory my usual practice has always been to use a Sinclair expander mandrel to resize the necks first.
All was going as expected for the first few, then one almost got stuck in the expander die requiring a lot of force to get it out. I hadn't changed my lube method.
This continued in varying degrees through 30 cases. I've attached a photo. The left batch were very difficult to size. The middle less difficult. The right were as expected, feeling slightly tighter than a fired case. I've not experienced this degree of variation before in Lapua. Clearly this will affect neck tension and the SD, particularly for load testing - if not that much for actual deer.
What do I do with the too tight ones? Ditch them?

 

[User00040]

 

[jcampbellsmith]

I would run the tight ones over a larger mandrel and then use as normal. Perhaps 0.2645 inch diameter or thereabouts.
Regards
JCS

 

[Jelen]

I would run the tight ones over a larger mandrel and then use as normal. Perhaps 0.2645 inch diameter or thereabouts.
Regards
JCS

I might have to resort to that as, if the trend continues, I could end up with maybe 40 cases out of spec?
It may seem trivial but, in my experience, it's unusual for Lapua.

 

[Cottis]

Is the internal neck measurement of the tight and loose examples the same after you have run them through the expander die. What do your calipers say?

Although you're experiencing differing amounts of effort when running the cases over a mandrel, I would still expectr fresh, annealed Lapua brass to give consistent measurements post sizing.

 

[xavierdoc]

Run a larger mandrel through all of them, resize, run usual mandrel through, anneal, load and use.

 

[kenbro]

I might have to resort to that as, if the trend continues, I could end up with maybe 40 cases out of spec?
It may seem trivial but, in my experience, it's unusual for Lapua.

Why are you using an expander die?
Surely easier to just use something like a K&M expander mandrel?
Ken.

 

[Utectok]

6x55 lapau are always tight new I anneal and expand then necksize

 

[Jelen]

Why are you using an expander die?
Surely easier to just use something like a K&M expander mandrel?
Ken.

The Sinclair expander die is a universal fit and doesn't touch the case body or shoulder. You just insert the correct sized mandril, In my case I use it for both .243 and 6.5x55SE. I bought it specifically for Lapua brass. The reason for the post is because I've been using Lapua brass for quite a few years and never experience such a large variety of neck tension until this batch of brass. Perhaps the QC isn't as good as it used to be?

6x55 lapau are always tight new I anneal and expand then necksize

As for annealing, Lapua comes ready annealed from the factory, so there shouldn't be a need to anneal new brass again, or am I missing something there?

 

[Donkey Basher]

Just because all the cases are from the same sealed box/batch don’t assume they’ve all been made using the same roll of brass sheet or that they’ve been made on the same machine. You may have some that were from a harder sheet of brass, or that've been formed on a machine with a new sizing due that’s at the tightest end of the tolerances, etc.

Personally I’d be more concerned at neck thickness & whether I’d need to change the bushing to get consistent neck tension when seating bullets.

 

[Utectok]

The Sinclair expander die is a universal fit and doesn't touch the case body or shoulder. You just insert the correct sized mandril, In my case I use it for both .243 and 6.5x55SE. I bought it specifically for Lapua brass. The reason for the post is because I've been using Lapua brass for quite a few years and never experience such a large variety of neck tension until this batch of brass. Perhaps the QC isn't as good as it used to be?


As for annealing, Lapua comes ready annealed from the factory, so there shouldn't be a need to anneal new brass again, or am I missing something there?

yes true annealed then sized.... but i guess we all anneal slightly differently but it your right it may be over kill

 

[Border]

@Hunter300

 

[paul o']

Guy on another post is crushing bullets and my new 300prc and 6.5cm brass were tight! so i'v prepped them all as if there dirty including a mandrel to get the same neck tension over the whole batch of 500.

 

[MarinePMI]

Everyone likes to believe whatever brand of brass thy use is the best, and most uniform. I get it.

But, listen to what your brass is actually telling you (and quit assuming based on the brand, that is at a certain state of readiness out of the box).

FL resize the brass, then neck expand. If that doesn't work, anneal it, and then do that same process again.

 

[Hunter300]

Many thanks to all you guys for the feedback. My friend spoke to Spud reloading and is currently waiting for a new “stem”, will keep you posted