Neck tension

[Klem]

With the stem removed there’s .006 of neck tension. Lee actually sells a pin with a .260 expander.

Scott,

That sounds perfect. You can either file down the existing stem until the bullets stop creeping, or buy the .260 expander and see if that works out of the box. Let us know how you go.

As you know, not all .264 bullets are the same thickness. Here's a chart of popular bullets used in Grendel. Bullet thickness is not critical to solving your problem but might be when you get into fine tuning loads. The OD is my die of course but the trends will be the same in yours. The takeaway here is that Nosler are slightly slimmer bullets and Hornady are slightly thicker.

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