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Posted: 5/8/2016 11:13:04 PM EDT
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Trying to make this 6.5x47 Lapua brass last as long as possible. For the first 4 firings I have only neck sized. Now they have become difficult to close the bolt and open it after firing. I took a few and played with the bump shoulder die I have from Forster. I bumped the shoulder back 0.002" and sized the necks. Cases are still sticky when closing/opening the bolt. I tried a full length sizing die and got the same results.
What am I missing or overthinking? I have some factory Lapua ammo left over, the bolt closes butter smooth with them. |
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I would check the diameter near the base to see if that is expanding but not getting sized back in your FL die. Actually, I would take a new card and mark it with a sharpie in 4 or 5 places along the case wall between the shoulder and base, and a sticky case in the same locations and compare diameters. Use your caliper with one edge on the face of the case head and the other to scribe a line to make sure they're at the same location.
Also you could paint an entire sticky case with sharpie and chamber it. Wherever it's making contact in the chamber should leave witness marks. |
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Quoted:
Trying to make this 6.5x47 Lapua brass last as long as possible. For the first 4 firings I have only neck sized. Now they have become difficult to close the bolt and open it after firing. I took a few and played with the bump shoulder die I have from Forster. I bumped the shoulder back 0.002" and sized the necks. Cases are still sticky when closing/opening the bolt. I tried a full length sizing die and got the same results. What am I missing or overthinking? I have some factory Lapua ammo left over, the bolt closes butter smooth with them. Keep screwing the FL sizing die intio the press until the cases chamber and extract with ease. Might take as much as 1/4+ turn past shell holder contact. |
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You want the shoulder set back .0015" from the fired case measurement. This is a good working headspace for most bolt action rifles.
The sticking is caused by the case binding against the chamber's shoulder. The only fix is to set the case shoulder back until it doesn't. |
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Quoted:
You want the shoulder set back .0015" from the fired case measurement. This is a good working headspace for most bolt action rifles. The sticking is caused by the case binding against the chamber's shoulder. The only fix is to set the case shoulder back until it doesn't. Not nesasarily. I have a lot of experience shooting neck only sized brass. Very often like described above, the body of the case, especially back in the web will cause the cases to fit tightly. A good full length sizing should correct this. Afterwards he should be able to neck only size until they get tight again. Motor |
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