They have an issue with the mag tab spring in the magazines (not the actual mag spring, the spring for that little tab in the magazine that pops up to hold the bolt back) not being strong enough sometimes to hold the bolt open, especially if the action is dirty or you're using weaker ammo... I think maybe it doesnt retract the bolt hard enough for the tab to have time to fully push the bolt catch up. These rifles are popular in the UK and there is a Facebook group for them, over there they install stronger springs to sort this.
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