Welcome! I'd start with the Handi Basics 101 sticky, you may need some eductatin on the aspects of the care and shooting of a Handi.
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Also, be aware that you'll need to full length size the brass when handloading for a break barrel, if you don't the action may not be locking up completely and there will be no accuracy, for the same reason oil on the latch/shelf will cause the same problem, consistent lock up of the action is essential. I have two 243 Ultra Varmints, they both shoot well under moa, one does exceptional well with factory ammo.
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Tim