Busta mailed to me a couple of these vent liner. They arrived here with a 0.028" flash hole.










The first was installed in the Mountaineer, and 48 shots taken, over two days. The flash hole eroded from 0.028" to 0.030".





This morning i installed the other vent into the X7, and went up and shot 31 shots. Returning home, i began my normal prodedure of cleaning the breech plug. First the vent liner was removed. The flash hole was measured at 0.029". Then a 5/32" drill was spun using a drill motor and used to drill through the carbon in the flash channel. When the 5/32" drill encountered the carbon deposit right at the end of the vent, it proceeded as though it was drilling hardened steel. The carbon deposit was thick, and had a small hole though it about the same diameter as the flash hole of the vent. Even though the drill was spinning at high speed, and i was leaning on the motor, it took some doing to drill though the carbon. This i had never experienced before yesterday, when the same thing happened when i cleaned the Mountaineer breech plug.

The vent liner(s) did not have a lead on the primer end. The vent liners i have been using lately, all had leads. The carbon deposit in the plugs when using those other vents had been a way easier to drill through. It seemed a lead should be created in this vent liner. It was done.














This afternoon, the vent liner was installed in the breech plug, the breech plug installed into the rifle, and a trip was made to the hills. Nineteen shots were taken whilst standing on my hind legs, and using a bipod. The shooting was stopped, because it began a lightning storm. I didn't feel comfortable loading the rifle with the ram rod pointed to the sky. Returning home, the vent liner with the lead was removed leaving behind a carbon deposit with a large hole in it similar to the diameter of the lead. The carbon was readily removed with the powered 5/32" drill.

What a difference the lead made in ease of cleaning. The carbon was so much easier to drill out, this afternoon, compared to this morning.

After 50 shots through the second Busta' stainless vent liner, it's flash hole is now 0.029".

The target showing the last 19 shots, was at about 102, or maybe 103 yard, shot standing, using a bipod. The load was 110g BH, 300g 44 caliber XTP, green crush rib sabot, W209 primer.