Scott is/was quite interested in seeing how Blackhorn works with direct ignition. Achieving direct ignition is trivially easy to do if one has a breech plug with a vent liner; alls one need do is remove the vent liner, and use the plug without. The first time i tried this was in
2012. Back then i used a shotgun primer, and it didn't work so good. The primer leaked soot between the anvil, and cup; the primer required a leatherman tool to remove it from the breech plug. This morning a Fedral 215 primer was used.
This morning a
pr adapter was used in a modified QRBP. The adapter allowed the Federal 215 magnum rifle primers to be used.
An o-ring was was used in the primer socket to stop blow by around the nose of the adapter. The first three shots beginning with a clean cold barrel were made with the vent liner in place.
Then the vent liner was removed.
Without the vent liner in place the powder nestles right up tight to the primer adapter, and it is as though one is using a cartridge filled with powder. Three shots were made on the target using 'direct ignition'. The adapters came right out of the breech plug using fingers.
Then a chronograph was set up in shade, and bullet speed was measured about 15' from the rifle. The load was 65 (weighed) grain Blackhorn, 265g 44 caliber FP interlock, smooth green Harvester sabot, Federal 215 primer. Rifle was an Optima with a 4X scope mounted.
First shots clocked were with the vent liner reinstalled in the breech plug.
1736 fps
1724
1736
1732 fps = average with vent liner
Next five shots made without a vent liner; powder right up tight to the primer.
1823 fps
1782
1836
1801
1841
1816 fps = average
The last photo shows the primers/adapters after. The primers to the right of the vent liner, fired with the vent liner in place.
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