How does shimming a scope affect bullet trajectory?

[ar15barrels]

I have red dots mounted at 2.75 to 3 inches height over bore and they zero to 35 yards just fine.
Why would the scope be so different?

Because it does not have as much erector travel as the red dots have adjustment range.

[audiophil2]

I think a sfp scope is less forgiving on eye placement compared to dots and FFL Scopes.

[Starslinger]

Run to home Depot or Walmart and get 2 small bubble levels. One on barrel and one on elevation turret. Amazon has really small ones too. Level the barrel and see what the turret bubke.looks like.

Thanks for this suggestion, Audiophil2! I bought the bubble levels and sure enough the top of the RS Regulate picatinny rail was not quite level with the barrel of the rifle. RS Regulate mounts are known to be high quality and I don't know how I managed to set the mount up unevenly but there it was.

I ended up moving the scope to my Saiga AK with Texas Weapon Systems Dog Leg Rail and moving the Romeo 5 red dot to the Lee Armory Hunter AK. I was able to zero both of these rifles at 35 yards this afternoon. In order to allow the Dog Leg Rail to pivot so that I can clean the Saiga, I had to mount the scope pretty far back. I can see through the scope though. I will blue Loctite everything, re-zero the rifles and then take the scoped Saiga out for an attempt at 300 yards soon. Wish me luck! And thanks for the advice everyone!

Here is a picture: https://imgur.com/a/69rYShm

[golfish]

Here is a picture: https://imgur.com/a/69rYShm

Oh my! That guns sure has some purdy wood.
Thanks for the pics

[SharedShots]

I have a scope that sits 3 inches above the bore of the rifle. There is not enough downward elevation on the scope to zero the scope - it is shooting several inches too high. I have never done this but in theory if I shim or use adjustable elevation scope mounts so that the front of the scope is higher than the rear, I will be able to lower the point of aim/impact for the bullet and zero the scope, correct? So, how would that affect the trajectory of the bullet? How do I determine the bullet drop at various ranges for target shooting? Can anyone link me to a web based trajectory calculator that allows me to input the amount of shim and then calculates the trajectory? Thanks for any help!

Given what others have already said:

Guns like all tools have different capabilities and it seems the one you chose doesn't give you what you want. Instead of chasing a ghost, maybe consider changing the tool? I bet that were you to ask which rifle/chambering/caliber/load/ammo/scope/mounts will get you where you want to be there would be lots of recommendations.

Perhaps you asked the wrong question?










.

[audiophil2]

Thanks for this suggestion, Audiophil2! I bought the bubble levels and sure enough the top of the RS Regulate picatinny rail was not quite level with the barrel of the rifle. RS Regulate mounts are known to be high quality and I don't know how I managed to set the mount up unevenly but there it was.

I ended up moving the scope to my Saiga AK with Texas Weapon Systems Dog Leg Rail and moving the Romeo 5 red dot to the Lee Armory Hunter AK. I was able to zero both of these rifles at 35 yards this afternoon. In order to allow the Dog Leg Rail to pivot so that I can clean the Saiga, I had to mount the scope pretty far back. I can see through the scope though. I will blue Loctite everything, re-zero the rifles and then take the scoped Saiga out for an attempt at 300 yards soon. Wish me luck! And thanks for the advice everyone!

Here is a picture: https://imgur.com/a/69rYShm

My eyes are old but that scope looked angled. Glad the levels helped. I've learned the hard way the simple solution is the right one. After going through about 50 rounds one day I realized I did not tighten my rings to the base. Zero, way off, zero, way off x 4 or so tries.

I sent one pic to my buddy that owns about 30 aks. He said that setup will flex anyway.

[ar15barrels]

Thanks for this suggestion, Audiophil2! I bought the bubble levels and sure enough the top of the RS Regulate picatinny rail was not quite level with the barrel of the rifle. RS Regulate mounts are known to be high quality and I don't know how I managed to set the mount up unevenly but there it was.

Ideally, you would have about 15moa of cant built into the RAIL or the MOUNT to account for the height over bore center.
This would cause the scope to be pointed down in relation to the barrel.
Take the RS regulate mount off the receiver and check just the rail against the barrel and see what you find.
It would not surprise me one bit if the rail was level or even canted the opposite direction.