Put one shot through it yesterday evening and the primer pocket is so big that fouling went everywhere, the primer bulged big time (measured in photo below), and the primer cup separated. Looks like the fouling leakage was caused by the separating primer and not blow-by between the primer cup and breech plug. Going to be calling MU today.
In addition to the primer pocket being too large in diameter, it looks like it is a tad too deep as well. There couldn't be more than 5 thousandths space between the primer flange and the plug when pushed into the primer pocket. Brand new #60 oring from MU got toasted on that one shot (in photo below next to a new one supplied by MU).
Plug dimensions:
Old MU Plug: primer pocket opening- 0.2470", bottom of tapered pocket walls- 0.2420", depth- 0.2870"
New MU Plug: primer pocket opening- 0.2650", bottom of tapered pocket walls- 0.2585", depth- 0.3120"
I talked to Bob at MU this morning and he requested that I email my pics to him. He says that he cuts the primer pockets himself.
He said that he had a supplier that was machining the plugs for him and the supplier quit machining the plugs. He said that he had only ordered about a 100 at a time and they didn't move very fast. Didn't sound like he was too eager to find a new supplier. Can't blame him...
In addition to the primer pocket being too large in diameter, it looks like it is a tad too deep as well. There couldn't be more than 5 thousandths space between the primer flange and the plug when pushed into the primer pocket. Brand new #60 oring from MU got toasted on that one shot (in photo below next to a new one supplied by MU).
Plug dimensions:
Old MU Plug: primer pocket opening- 0.2470", bottom of tapered pocket walls- 0.2420", depth- 0.2870"
New MU Plug: primer pocket opening- 0.2650", bottom of tapered pocket walls- 0.2585", depth- 0.3120"
I talked to Bob at MU this morning and he requested that I email my pics to him. He says that he cuts the primer pockets himself.
He said that he had a supplier that was machining the plugs for him and the supplier quit machining the plugs. He said that he had only ordered about a 100 at a time and they didn't move very fast. Didn't sound like he was too eager to find a new supplier. Can't blame him...
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