refuse2bafool
Member
This is in reference to the “plunk test” sticky on the reloading library of wisdom by Walkalong. I am not a novice, but far from an expert. My ammo always goes bang and I can get 1.25” or less groups with a stock Milspec at 50 ft. Any error is probably mine. However, one thing always bothered me when it came to loading 9mm and .45acp.
How does OAL impact the head spacing as shown in Walkalong’s sticky? If the round headspaces on the case mouth contacting the end of the chamber (where there is a step that reduces diameter) why would OAL matter as long as the bullet does not engage the lands?
My rounds pass the plop test, but I notice that they may “stick” just a bit in the chamber of the barrel. They may not drop out cleanly when I invert the barrel unless the OAL is very short. They are easy to extract, but factory rounds don’t exhibit this behavior even if I push them in hard with my thumb.
I used Tilos method to determine theoretical max OAL and I am a good 35/1000 or more short of that at 1.165 OAL on a .45 with a flat point having a large taper. Even allowing for error in that method I don’t believe the bullet is contacting the lands.
My gut tells me not to worry about this too much as long as the base of the cartridge is at or slightly below the breech and I get good results, though comparing mine with Walkalong’s pictures I may be spacing on the extractor if anything. Maybe I should just try for flush or just below?
As far as hard data with the particular round I am using right now:
0.451” 185gr plated flat point diameter
OAL = 1.160-1.165”
Tapered to 0.469” at the mouth of the case.
Cases trimmed to SAMMI min of 0.888.
Any insight would be appreciated.
How does OAL impact the head spacing as shown in Walkalong’s sticky? If the round headspaces on the case mouth contacting the end of the chamber (where there is a step that reduces diameter) why would OAL matter as long as the bullet does not engage the lands?
My rounds pass the plop test, but I notice that they may “stick” just a bit in the chamber of the barrel. They may not drop out cleanly when I invert the barrel unless the OAL is very short. They are easy to extract, but factory rounds don’t exhibit this behavior even if I push them in hard with my thumb.
I used Tilos method to determine theoretical max OAL and I am a good 35/1000 or more short of that at 1.165 OAL on a .45 with a flat point having a large taper. Even allowing for error in that method I don’t believe the bullet is contacting the lands.
My gut tells me not to worry about this too much as long as the base of the cartridge is at or slightly below the breech and I get good results, though comparing mine with Walkalong’s pictures I may be spacing on the extractor if anything. Maybe I should just try for flush or just below?
As far as hard data with the particular round I am using right now:
0.451” 185gr plated flat point diameter
OAL = 1.160-1.165”
Tapered to 0.469” at the mouth of the case.
Cases trimmed to SAMMI min of 0.888.
Any insight would be appreciated.
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