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Until your brass grows to the size of your chamber there is no need to bump the shoulder yet. Set your FL sizing die to just size the neck. You can check with your comparator to see if you’re bumping the shoulder.
I would pass on a Mark4 from my experience. Can’t comment on the other 2 choices.
For hunting a SFP is a better choice for me. FFP starts out too small on low power and hog up the field of view on high power.
One thing I would add is once primed primers are looser when reused. With only 20 primers I would fire the cases off and not worry about an accident in depriming them.
I bought the BoreTech carbon remover to try to clean the carbon build up in the 338 WM. I bought the rifle used and it had a layer of volcanic black glass. I even left a wet patch in it overnight and hit it with a bronze brush the next day , didn’t budge. I lent up soaking a patch of Kroil for a...
Over the years I’ve tried several products and learned what works and what doesn’t.
Hoppes was the first many years back. Without a borescope one thought it was doing a good job. When I got my 30-378 thats when barrel cleaning became more rigorous. At the time I bought one of those cheap...