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Originally posted by kraky:
NEVERFLINCH-I'm confused about what you did. Are you saying you made an exact duplicate of the Federal load except for powder charge? And these got stuck in the lands?? Did the federal loads "stick in the lands"?

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r ignites and the primer now backs out just slightly (a few .001") and hits the bolt face making it look like a high pressure flattening of the primer. This type of situation give the appearance of high pressure problems when there is no problem at all. If you have a friend with a headspace kit it would be interesting to take measurements off of the new federal rounds and compare them to the once fired brass that now is a "mirror" of your chamber dimensions.

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Originally posted by Atkinson:
Sounds like you didn't trim the cases and they are too long or your chamber is too short...It has to be one of the other.

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Almost a duplicate, the reloads were .015" longer and got stuck the factory rounds did not. I was wondering if this short throat could cause enough of a pressure spike to flatten primers.

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Originally posted by El Deguello:

Flattened primers can be caused by a number of things, high pressure being merely one of these......

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Originally posted by Bill Mc:
When you measure the length, is it overall length or from the "ogive" of the bullet?

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Originally posted by Stonecreek:
Primers that give a flattened appearance in factory loads usually indicate that the headspace is somewhat generous. This doesn't mean that your rifle has "excessive" headspace. It just means that the factory loads are at minimum and your chamber is not. What happens is that the cartridge is shoved forward upon firing toward the front of the chamber. At the same time, the primer is backed out of the pocket slightly by the building pressure, until it contacts the bolt face. As the pressure continues to build, the case itself stretches and is shoved back against the bolt face, reseating the now slightly swelled primer. This causes the "flattened" appearance that is often mistaken as a sign of high pressure. Absent ridging around the firing pin imprint or other pressure "signs", this abundance of headspace with factory loads is the likely cause.

As to "dupicating" the factory loads with the "same" bullet, be aware that the bullets sold to the manufacturers often vary from those sold to handloaders. The "same" bullet may have a slightly different ogive, and factory bullets often have cannelures absent on reloader bullets. As a result, seating to the same length over all with the "same" bullet may or may not duplicate the relationship of the bullet bearing surface and the lands of the barrel.