I have a James River Restoration Garand that was done 10+ years ago off a very worn 5XX,XXX Springfield.  Honestly, I only test fired it, I never fired it at longer ranges until this past weekend.  The below pic is what happened at 50 yards with the sight at the BOTTOM of its travel.   It's shooting 3.5 inches high at 50, which by ballistic tables is around a 15/375 yard zero.  

I read/saw that it typically takes 7-14 clicks to get up to a 100 yard zero.  The below is with the sight bottomed out.  Do I get a taller front (seems logical, but is this a normal action?), or do I ghetto it and buy another rear, then hack the bottom so it can retreat even further down into the body? (it won't take much, although the sight will get .22lr low)

I realize that everyone is a better shot than I am, and all others could do this group at 500 yards.  However, with my aging eyes, I'm Ok with this group...

Thoughts?

Try a 6 O'clock hold.  Great group.

You need a taller front sight

Yes.

But before doing that, you really need to determine how high (or low) your zero is off with a couple of clips of that HXP fired at 100-yds minimum, using the aforementioned 6'oclock hold. 50-yds doesn't tell you much, other than showing that, technically, you're "on paper."

Once that's established, you can figure out whether a taller front sight is really needed.

Regardless of make of ammo, my minimum zero for both my '06 and 308/7.62 Garands is 200-yds.

Get a taller front sight if available.

Your front sight may have been shortened.  Measure it and see if you can post up numbers.  
someone can tell you if it is shorter than stock.

Could be a stock issue.

I have a CMP Winchester that shot great in the factory stock. A while back I swapped the stock for a Boyd's to preserve the original GI wood. Windage was OK but elevation was way off.

Widening the barrel channel to eliminate contact with the barrel solved the problem.

Is the GI NM front sight taller than the issue sight?  Or is my memory telling me lies?

I know it's thinner but seems like maybe it's taller, too.

I'm failing to see how the ballistic math doesn't work.  My goal was 1.25 high at 50, which would be a 200 yard zero and a little over 2 inches high at 100.  My calculations using it's current condition would result in being 7.5 high at 100, and 11 high at 200 before falling to 0 at around 375.  Them's is Carcano numbers...

Interesting. I wasn't aware it could make that much difference.

It's unmarked and doesn't appear altered.  I'll measure it shortly.

I'm not a fan of 6 O'Clock holds.  I get it for fixed range target shooting with specific target types.  I just dig POA.

Well, even 300-yds is a good practical 'battlefield' zero for any M1, if that's what you're after. In fact, one of my grab-n-go/'shooter' .308 Garands is zeroed for 300 with the IMI 7.62 stuff.

That said, if your front sight has been shaved, a taller NOS M1 sight shouldn't be too hard to find (or expensive).

do you have a NM rear sight?

I was think this might be the cause. The NM rear sights need to be filled on the bottom to get a 100 yd center zero. The instruction online are here, NM sight fitting

Trimming the bottom is done so you have a solid click (not a mushy one) when you bottom the sight.  I'm fairly certain the Nm aperture will get to 100yds without doing that.  But either way, it's not a bad thing.  Not sure you can get what he needs (8 minutes?)  at 0.008" per minute.

ETA:  Ha! Nevermind!  The Kuhnhauausen M1 shop manual literally says "trim for 100yd zero" on the aperture drawing.  And the note isn't specific to the NM aperture.

Also, an unmolested Front sight is 0.728" +0/-0.005" from bottom to the top of the blade.

The rear is not a NM.

The top of the blade is .035 below the wing height. (As best as I can determine)

Got a picture of the rear sight from the rear?

Ah dude,   ... just looking at it you can tell someone shaved that sight.

Don't have to be an M1 Pro to know that a taller/'standard' front sight will drop POI.

What would indicate that sight has been shaved? Top and back end look about right. There is no need to shave a M1 sight, just click the knob for elevation.

A lot of guys don't like having to click-up 15-18 clicks from base just to get on paper @ 100yds. Not all M1s click-up in the same count due to variations when the barrel was installed. This is a known 'thing' with Garands. It's not about accuracy per se, it's about POA/POI in relation to the number of clicks up (or down) needed to establish a certain zero, e.g., 100yds.

Yes, there are certain 'rules of thumb' that say for 'most Garand' starting from base 5-8 clicks up will put you on at 100yds, +3-4 more clicks up will put you in the black at 200yds, etc. But those are just general. They aren't the same on every M1.

That's why if one guy finds he has to click-up 14 clicks from base just to get a group in the black at 100yds, he might shave the front sight so that it's only 5-6 clicks at 100yds.  Plus, many regular M1 shooters don't like that rear aperture cranked up really high because they find (when shooting prone) that they have to raise, or re-adjust, their cheekweld from its normal position just to get a solid sight picture. To stay consistent on cheekweld when shooting out to 300yds or even 600 yds, it's an easy 'fix' just to shave down the front sight as needed. (Or in many cases, to shorten that stem on the rear aperture. Same idea).

It sure could. The stock should provide downward tension on the barrel group ie,, the barrel should not just lay flat and dead on the stock. Up at the Ferrell on the stock it should be making concentric contact with your barrel band and if the upper and lower are squeezed you should see the two parts move apart.  Same applies to the M14 stock.