The scoped X7 using OEM breech plug has a snug headspace. One can use CCI, CCIm, Federal 209A, and W209 primer, and the spent primer is either near the same length as the unfired primer, or shorter. Of course, bein' it uses the hex head TC breech plug, it never fails to ignite BH. This rifle is the only rifle i own, that uses an unmodified breech plug







The factory sighted X7 has a looser headspace when using the OEM breech plug. In this rifle, W209 primer grow a couple of thousandths, and shorter primers allow quite a bit of blow by. Even though this rifle's headspace was near perfect for using W209 primer, i just couldn't let it be.






















The technique of tapping the plug to receive a grade 8 3/8" bolt, was shown to me by Screwbolts. This breech plug is now sized so that it gives a slight crush to the STS primer when used in the peep sighted rifle. Seems, it won't work in the scope sighted rifle, but i haven't tried it to see.

Both breech plugs are showing erosion of their flash holes i.e. the flash hole diameter is now about 0.031". When new they were about 0.029". One day it will be time to install a vent liner in each plug using the technique explained by sabotloader on these forum