Stone,
I'll add two comments.
The idea that there's 'No such thing as a cold bore shot, only a cold shooter' is one of those neat sayings that adds its own credibility, but only because it sounds neat. Of course the first round out of a gun that has been idle for 6 months is [on average] not going to print in the same place as the previous session. Especially if it has been cleaned and/or lubed in any way. Even if not I can imagine if not touched the internal coating of carbon will change as moisture slowly works on it over the months. Then there is the external temperature difference between firing sessions, and the internal temperature difference of the breech. Your firing position on the gun may also be different. If the gun is precise enough the shooter will see a difference, and hopefully that difference is predictable... But I know you know this.
My other point is that I have never seen shoulders and necks like that on a Grendel. I anneal now but did not use to when first starting on this calibre. I know annealing is doing something as the feel when seating bullets is stiffer than before. But to be honest, I have not seen any improvement in accuracy, not even a tiny bit. The induction annealing wand cost a few hundred dollars in parts so that will have to be compared against how many more firings I get. Again to be honest, I don't know because I've never had to retire any of the original brass. The price of brass here is three times higher than when I first got it so I imagine annealing will pay for itself eventually - just when, I don't know. Plus I've paid for the setup so feel obligated to use it. As with Zene, it takes time - roughly 6 seconds per case. I set it up and over a couple of days do it in batches of about 30 at a time.
I'll add two comments.
The idea that there's 'No such thing as a cold bore shot, only a cold shooter' is one of those neat sayings that adds its own credibility, but only because it sounds neat. Of course the first round out of a gun that has been idle for 6 months is [on average] not going to print in the same place as the previous session. Especially if it has been cleaned and/or lubed in any way. Even if not I can imagine if not touched the internal coating of carbon will change as moisture slowly works on it over the months. Then there is the external temperature difference between firing sessions, and the internal temperature difference of the breech. Your firing position on the gun may also be different. If the gun is precise enough the shooter will see a difference, and hopefully that difference is predictable... But I know you know this.
My other point is that I have never seen shoulders and necks like that on a Grendel. I anneal now but did not use to when first starting on this calibre. I know annealing is doing something as the feel when seating bullets is stiffer than before. But to be honest, I have not seen any improvement in accuracy, not even a tiny bit. The induction annealing wand cost a few hundred dollars in parts so that will have to be compared against how many more firings I get. Again to be honest, I don't know because I've never had to retire any of the original brass. The price of brass here is three times higher than when I first got it so I imagine annealing will pay for itself eventually - just when, I don't know. Plus I've paid for the setup so feel obligated to use it. As with Zene, it takes time - roughly 6 seconds per case. I set it up and over a couple of days do it in batches of about 30 at a time.