Novemberain

I was going over my targets and load data and my best group is 3/4" center to center using barnes 290gr with 100gr of blackhorn 209 at 75 yds. I used a crushed rib sabot that slid into the barrel with little to no resistance. On a scale of 1 to 10 resistance was a 2. At the range it is not a problem but I am concerned that out hunting is it possible for the sabot to slide some and create a gap between breech plug and bullet. I measured my bore at .502 and and the black crushed sabot and bullet at .502 to .503. Any opinions on using the red crush sabots for a tighter fit.

Semisane

I would try the Harvester smooth black sabot rather than the red crush rib. I've never had much luck with the red one.

Novemberain

Thanks. I have some on order and hope they keep a tight group.

bronko22000

November - you should have more resistance than that. Using your scale of measurement with 1 being just about falling down the bore and 10 being having to beat it down with a mallet you should have a range of 6-7.
You want to start the bullet with a fair amount of pressure with your short starter. Then the bullet should go down with enough resistance that you will have to pull down on the ramrod with a "fair" amount of pressure and then lean on it hard to seat it on the powder charge - especially with BH209 or Black MZ.
A little tip, if you don't have one of those palm savers on you ramrod, drill a 3/8" hold in your short starter about 3/8" deep to put on the end of your ramrod to apply the final pressure.

GoexBlackhorn

#2 is too light. Good idea to switch to regular short Harvesters. Another option is MMP HPH24. In my findings, they seal a smidge tighter than the Harvester Crush Ribs.

Gm54-120

In a .502 bore i would try a MMP HPH-12 but there is a chance the Harvester smooth black or HPH-24 might work.

The HPH-12 will be about .004 over land size in a .502 bore with a .452 bullet. Slightly less with a Barnes since they run a little smaller.

BTW the Barnes TEZ bullets come with a HPH-24 sabot.