Beginning handloader question:
My Winchester 30-06 (Model 70) flattens primers. It does it with factory ammo (Winchester Failsafe 180 gr. & Remington Core-Lokt 150 gr.) and it does it with my handloads (Barnes TSX 180 gr. BT). Even with the starting charge of H4831 my primers (CCI 200) lose their rounded backside and develop a bit of a corner. Now that I’ve worked my way up to charges near the max listed loads, I’m noticing sharper corners.
The Remington factory loads have an initial primer seating depth between .003 and .005”. Once fired, the primers sit flush. The Failsafe primers don’t back out at all. My handloaded primers occasionally back out to flat, but it’s one out of every 5 or 6, and not predictably -- that is to say, none of the primers backed out at a powder charge of 45.5 grains, and one did at 46, but none at 46.5.
Here’s what I’m not noticing:
1) Case head expansion. Both factory and handloaded cases range from .463-.4645” immediately forward of the extractor groove, which is the same variance I measure with unfired cases.
2) I don’t notice any primers cratering around the dent the firing pin leaves.
3) I don’t notice any shiny spots or cuts in the headstamp area.
4) The primers aren't totally flat - they're flatter. I don't have a good way to measure how much.
4) Heck, I don’t even see a pressure ring where the case web tapers off.
Since my rifle just seems to flatten primers, how do I look for signs of excess pressure? The Barnes folks don't have published data for the TSX. They say you can work the TSX up to more than the listed max load for the X bullet by 1 or 2 full grains if you're careful. I aim to try, as long as the groups stay tight, but I need to figure out what my warning signs really are.
Or am I missing something important here?
Appreciate any insights...
My Winchester 30-06 (Model 70) flattens primers. It does it with factory ammo (Winchester Failsafe 180 gr. & Remington Core-Lokt 150 gr.) and it does it with my handloads (Barnes TSX 180 gr. BT). Even with the starting charge of H4831 my primers (CCI 200) lose their rounded backside and develop a bit of a corner. Now that I’ve worked my way up to charges near the max listed loads, I’m noticing sharper corners.
The Remington factory loads have an initial primer seating depth between .003 and .005”. Once fired, the primers sit flush. The Failsafe primers don’t back out at all. My handloaded primers occasionally back out to flat, but it’s one out of every 5 or 6, and not predictably -- that is to say, none of the primers backed out at a powder charge of 45.5 grains, and one did at 46, but none at 46.5.
Here’s what I’m not noticing:
1) Case head expansion. Both factory and handloaded cases range from .463-.4645” immediately forward of the extractor groove, which is the same variance I measure with unfired cases.
2) I don’t notice any primers cratering around the dent the firing pin leaves.
3) I don’t notice any shiny spots or cuts in the headstamp area.
4) The primers aren't totally flat - they're flatter. I don't have a good way to measure how much.
4) Heck, I don’t even see a pressure ring where the case web tapers off.
Since my rifle just seems to flatten primers, how do I look for signs of excess pressure? The Barnes folks don't have published data for the TSX. They say you can work the TSX up to more than the listed max load for the X bullet by 1 or 2 full grains if you're careful. I aim to try, as long as the groups stay tight, but I need to figure out what my warning signs really are.
Or am I missing something important here?
Appreciate any insights...
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