The designer of the front sight base for this rifle was smart and made the gas hole
in the base fatter than the gas port so we could be reasonably sure to capture gas in the event of a less than stellar alignment of the two holes.
It's rare for this hole to get plugged up completely, as Remington designed the gas hole
to self-clean as the gun is fired.
A gas hole
forms when the gas pressure, at any point, exceeds the head pressure and is influenced by the mold's ability to release the gases generated in the mold (permeability).
noted that the presence of Al in cast iron can cause serious gas hole
defects in castings.
Manufacture: Castings shall be of uniform quality, free from sand holes, gas holes
, shrinkage, cracks and other surface defects.
Common defects encountered in permanent mold castings, such as dross and associated gas holes
, blow holes, pinhole porosity, misruns, cold shuts and cracks, are similar to those experienced in other processes, but the approach to eliminating these defects can be different.
These included known geological data, drill logs and drill cores from previous oil and gas holes
that intersected the Namurian shales, and coal mining surveys and data that is publicly available from the huge data base generated by the coal mining industry.
RPS Group was commissioned by Eden Energy to analyse drill cores from previous oil and gas holes
from the 1970s, thousands of feet underground in the region's Namurian shale.
Because of the process we use, you don't have the gas holes
, inclusions and the defects that are normally associated with an iron casting.
The permanent mold process used to produce Dura-Bar XL is designed to virtually eliminate casting defects such as gas holes
, inclusions, and hard spots.
Cheese may be loose and open, and may have numerous sweet holes, scattered yeast holes and other scattered gas holes
While differing somewhat from its traditional continuous casting, the permanent mold process used to produce XL uses the same quality melt stock and is subject to the same quality processes designed to virtually eliminate casting defects such as gas holes
, inclusions and hard spots, Dura-Bar said.