emmab,
You mentioned that one of your M14 rifles is zeroed for 100yds/m with 8 and the other 12 kliks from absolute bottom? Have I got that one correct?
Okay M14 lovers in CGNutz Wonderland:
Here's how to lower that klik count (learned from my NRA High Power shooting days) to a nice single digit value (like 8 or 9 kliks).
* Go to your range, benchrest, sandbag in your M14, grab your ammo, screwdriver, variety of files/rasps
* Use a bullseye target 100yards/meters from your bench (either center or 6 o'clock hold will work)
* shoot a group to confirm your 100m/yds zero then count the number of kliks to absolute bottom. You happy now?
* If your count to absolute bottom is double digits (like 11 or 12 or 15 or more), grab your file
* Start filing downwards (see the slope of the factory front sight blade?) and towards muzzle of flash suppressor
* Keep the file FLAT, keep the profile of the front sight blade square (from the rear sight, I mean)
* Give it about 5 to 10 strokes, if you brush the side protector wings of the front sight then Birchwood Casey Cold Blue Paste is your friend. Use Q-tips to apply.
* Shoot another group of 3 or 5 rounds
* Observe to see if you need to LOWER your rear sight aperture. AHA! The magic is working.

Hungry knows WTF he's doing!

* Keep doing this until your klik count is about 8 or 9 kliks from absolute bottom. That's it!
* Final inspection, look through rear sight aperture, ensure edges are square, then COLD Blue the freshly filed metal surfaces.
IF YOU FZck things up and go too low... front sights are not that expensive (I've done this

). And that's why I'm your advisor/mentor for all this M14 fun... It's because I've fzcked up more times that all of you... well except for Laz2000 and M14doctor... they are catching up to my antics!
And here's the anecdotal funny story (for those of you who have attended my M14 clinic).
I established a low rear sight click count of SIX

for obtaining a super low cheek position for the Stage 1 of the NRA High Power NM course of fire; 200 yard off hand/standing position. I used the Sierra MK 168 gr bullet with 42.5 gr of IMR 4895. Well halfway through the season I ran out of IMR 4895 and switched to our team's load of 43.0 gr W748.
My SIX clicks was too low! :facepalm:

D'oh!! Too low for the 100m zeroing bull target. And yes, I was competing with a Springfield Armory M1A with NM barrel and McMillan fat bastard M1A heavy stock. Apparently I shaved off too much metal from the front sight, my coach laughed at this because he too made that mistake many years ago! Hey, it's all good!
I had to buy another front sight and start this process all over again. Cost me $ 10 for the front sight and $ 15 for mailing and tracking number.
Okay, get those files out and 'have at 'er!!
Cheers all,
Barney