Jay Christopherson
Not An Admin
In the quest for ever more precision, I decided to see what I could come up with to turn my Sinclair OAL tool from a "nearly repeatable" tool to a "perfectly repeatable" tool. Originally, I was able to get the same reading within .003 to .004 or so. With this simple mod, I can get *exactly* the same reading over and over. Not within .001- *exactly* (ok, less than .001" anyhow. My caliper doesn't read any finer than that). I just took 5 readings on my rifle and all 5 were exactly the same.
It took me maybe 4 - 5 tries to get the technique right, but once I found it, it worked over and over.
I bought a compression spring and a collar from McMaster-Carr (parts #9434K83 and #9943K16) and added them like so:
(sorry for the cell phone pic quality)
leaving about one coil worth of spring above the top of the rod. In use, I simply press on the spring until my thumb contacts the top of the rod. You get the same pressure every time.
Hopefully this helps someone out. Maybe it's already been done. I talked about this once or twice with the Forum Boss, trying to brainstorm some way to make the measurement the same everytime and this was the simplest thing I could think of.
If you don't have a problem with OAL measurements, then I guess this won't be helpful...
If you're a little frustrated, this might help.
Plus, it's cheap. You could probably get the same parts at any hardware store, but I was too impatient to go hunting for them.
It took me maybe 4 - 5 tries to get the technique right, but once I found it, it worked over and over.
I bought a compression spring and a collar from McMaster-Carr (parts #9434K83 and #9943K16) and added them like so:
(sorry for the cell phone pic quality)
leaving about one coil worth of spring above the top of the rod. In use, I simply press on the spring until my thumb contacts the top of the rod. You get the same pressure every time.
Hopefully this helps someone out. Maybe it's already been done. I talked about this once or twice with the Forum Boss, trying to brainstorm some way to make the measurement the same everytime and this was the simplest thing I could think of.
If you don't have a problem with OAL measurements, then I guess this won't be helpful...
If you're a little frustrated, this might help. Plus, it's cheap. You could probably get the same parts at any hardware store, but I was too impatient to go hunting for them.
