How to measure a locking shoulder?

[screech-fnfal]

I have 6 locking shoulders, what is the proper way to measure these for size? :confused:

[stimpsonjcat]

If you look at the LS in you weapon, you'll notice the the 2 sides which are ground flat to an almost 90 degree cut. Make note of which side the LS is inserted from and then use a caliper or micrometer to measure the distance fromt the forward (not upward) facing flat to the back curved side of the LS.

i.e. if the LS is out of the weapon measure from the flat which is perpendicular to the ear on the LS to the round back of the LS.

Best to take measurements across the face as wear may be uneven. Certainly if you are modifying one to make it smaller, you should measure often and all the way across the face.

[FXE]

Here's a little sketch of where to measure LS Size!

http://pstr-m03.ygpweb.aol.com/data/00C/02/7C/DF/1D/F+TkspQtCTlPq+xm6idUvxrDx3uVpoK00180.jpg

HTH
FXE

[screech-fnfal]

Thanks for your help :D

[stimpsonjcat]

Nice job FXE!

Yo Gary...FAQ material here!

[BRM308]

A word of caution for those not familiar with measuring tools.All dial type calipers have a built in error of about .002. Even digital calipers, unless your experienced in handling them, can vary even more. use a good quality micrometer and learn how to use it properly.Since headspace is involved I thought I'd put in my two cents. As soon as I can figure out how to transfer documents from my scanner to the web I'll post Starrets' treatise on micrometers.