Experienced reloaders know that belted bottlenecked cases should headspace on the shoulder, not the belt. This improves case life and accuracy, and reduces the risk of head separations. Speer is clear about this in their manuals (#14, pg 602) but who bothers to ever read anything in a reloading manual besides the load data?
I have headspaced my belted cases on the shoulder for decades and have never lost a case to an incipient head separation. I can reload my cases as many times as I want to, some have exceeded 20 cycles using my standard sizing dies.
Because the Encore lacks the strong caming action that a bolt rifle has, you may find that neck sizing will eventually result in cases that are hard to chamber, or an action that refuses to close all the way. The solution is to just bump back the shoulder in the sizing die - smoke the shoulder so make it easier to see when your die makes contact. This will help eliminate tight chambering or a gun which will not lock up.
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