Neither of my rifles have lands at .500 Maybe yours is different. The ribbed sabot with .429 XPB loaded measures .505 at the bullet base just ahead of the sabot web. IIRC the green sabot base is .503. Best I can measure the barrel grove diameter with calipers they run .500 to .501. Pretty sure the load will seal. Hornady .45s in the black Harvester slick sabot measure .509 same place. While I was measuring I checked the TC Shock Wave.50/.40 with 200gr SST. It measured .511 at the bullet base across the petals. Tough loading but I don't know what sabot they use.
“When Tyranny becomes Law, Rebellion becomes Duty”
Colossians 3:17 (New King James Version)
"And whatever you do in word or deed, do all in the name of the Lord Jesus, giving thanks to God the Father through Him."
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