[panther308]

Have a really stupid question ? Have never really messed to much with the irons on my M1A and since I recently started my conversion to a Scout Squad I want to have a better understanding of the rear sight elevation settings, I know from reading the TM to basically set the rear sight all the way down then shoot some rounds at 100 yards and adjust accordingly and then loosen the elevation knob and set it for that distance but after looking at the knob I see there are more than just numbers on it.

Has the following:

M
11
2 thru 8
A
S
10
then back to the M

I can only assume the M is meters but I don't see a 1 for setting it for 100yrds and I surly don't understand the other letters

Sorry if this is a dumb question

 

[panther308]

I asked another Member about this and he suggested I ask the Group as he has never encountered this, I took my rear sight down for a complete cleaning and there was some type of grit inside and upon removing the snap ring from the elevatin knob and pulled it out to clean and paint some reference marks a beveled washer fell out and I am not sure of the correct orientation for reassembly.

I have it put back on like this and not sure if it's correct but it looks right:

 

[NoExpert]

Either way is fine for the wave spring.

Now for the markings...

M designates meters

11 is 1100 meters

2-8 is 200-800 meters

Should be "SA" for Springfield Armory (commercial units are marked "SA")

10 is 1000 meters

There should be a horizontal line below the "2", this is the 100 meter mark.

 

[bd111]

If you've got a snap ring it's a commercial SAI elev pinion.

 

[panther308]

Thanks Guys for the info (kinda goofy putting the SA or AS where they did) , anyway now I can offically say I have had every part out and disassembled except for the barrel.

Here are a few more pics of the rear drum assembly:

Here it is with the "O" ring on the back side:

Here is the completed assembly sitting inside the elevation knob:

And here is the completed assembly with snap ring installed:

The only thing I did different was after snapping all the pics I looked at the assembly a few times and finally ended up flipping the spring washer over, the more I looked at it the more it looked like it was supposed to be that way.