The Wyatt's extended mag box isin't that hard to install even without a mill , have seen a couple that were done with just a dremal tool and files and come out ok worked well also , for the money their are a great upgrade. They also make a standard size mag box that comes with the flat follower thats desgined for better feeding from the center of the mag. What happens alot of the time even with non WSM's is that the shel is only beig held in the mag by one of the feed lips and once it gets glose and looses enough pressure the round "jump" loose from one side and pops out , having both of the lips on the mag box holding the round helps it slide out strait and most of the time if its fitted right the nose of the bullet is secured and keeps the round at home when it comes free.
I also have an issue with the way that Remington sets their barrels up for the bolt nose but that is part of their "3 rings of steel" crap and it makes for poor feeding with alot of rounds especialy the ones with steep shoulders. It s very easy fix if you have a lathe and a way to get the barrel off.
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