Question on scope bases??

T

T-CAIN

New member
Can somebody explain to me why scope base on some rifles have to be larger in the rear. Why do some have to have a 20 moa or a 15 moa? Why cant they just be flat? I want to get picatinny rail style base for my 700 and I dont know if I should order a 15 moa or a 20 moa. Any info would be greatly appreciated. Thank you.
 
Bases on MOST bolt rifles are taller in the rear because on most bolt rifles the rear receiver bridge is lower. The base has to be thicker to get the scope level.

The rails are that way to allow more scope adjustment for long range shooting
 
So my next question is the two piece bases that are on the rifle now, the one in the back is higher. Can I go with a flat base and still have enough internal adjustment in my scope to reach zero?
 
I want a one piece base, either luepold, or a picatinny type. To me the one piece just seems like it would be a stronger base. Does the luepold base actually have and adjustable windage screw in the rear?
 
I would recommend these. http://www.midwayusa.com/product/12...h-integral-1-rings-remington-700-matte-medium

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Watch their video on their site. He says "If these ever break or fail you, we want to hear about it because you probably got attacked by a rhino or something" lol.
 
20 MOA bases are used as said to extend your elevation of your optic for longer range. Here is a good explanation by Zak smith.

Zaks Smith said:
The way to get around this is to use an inclined scope base. An inclined scope based has some downward "slope" built in. An inclined base with 20 MOA angle will shift the zero point in the scope further away from its top extent. For example, with the 60 MOA scope described before, instead of being zeroed around +30 MOA (its center), it would be zeroed at about 30 - 20 = 10 MOA up from bottom, and have about 30 + 20 = 50 MOA "up" elevation left. Now instead of running out of elevation travel trying to dial 31.5 MOA, the scope will dial freely up another 50 MOA-- when it is dialed to 31.5, it still has 18.5 MOA left for dialing to longer distances.
Click to expand...

http://demigodllc.com/articles/practical-long-range-rifle-shooting-optics/?p=4
 
Might I add that if this is a hunting rifle and you don't have the need to take the scope on or off the rifle or take really long shots and need the extra MOA adjustments that a picatinny base would give then the Talley One peice rings are the way to go. IMO
 
I guess I'm the odd man out. To me, two-piece bases will be as sturdy as one piece bases if mounted right (mainly with the right torque). On bolt actions, the one-piece base typically limits access to the receiver, especially bad if you have a fixed magazine. I also tend to go with quick-release ring systems that allow me to take a scope off for cleaning without having to re-sight the rifle. Most of my guns have Warne mounts and rings; I wish I could afford EAW, but they are out of my range.
 
I agree. If you wack a scope hard enough to move the two piece base set up, you probably are going to have a scope problem anyway. Years back two piece bases got a bad rep from the shimming involved (very little scope adjustment years ago). I have a 99 Savage with a two piece tip off set-up that retains zero no matter how many times I move the scope or take the barrel off. Good old Weaver rings and bases are good enough for me and you can pull most scopes off and put them back on with out a problem.
 
On a hunting rifle either the Talley Lightweights or DNZ mounts are really the best way to go. I think the Talley's look a bit better and they are very slightly lighter. The DNZ are probably the toughest mount you can buy without going to an expensive rail and rings costing hundreds of dollars just for the mounts.

No need to use the Leupold windage adjustable mounts. They would be my last choice and I'd only use them If I had no other choice.

1 piece, 2 piece, it doesn't matter. Trust me, the scope is gonna break long before either mount does. I generally like 2 piece better because it doesn't obstruct the loading/ejection port. Makes it a lot easier to load and unload the gun.

If it is for a target rifle then I'd go with a rail and good quality steel rings. Although I'm hearing of some guys using the DNZ mounts for this.
 
I appreciate all the info guys, thas why I love this site!! I think maybe I would like to get back to the question of bases being flat. On a remington 700 does the back base always have to be thicker than bthe front? I didn't know if that was what 20 moa meant on a one piece base. I know all of this probably makes me sound like a dummy but I have always had my scopes mounted by somebody else, now I want to start doing it myself and I guess I have never really put a lot of thought into the bases. I get that the back of the reciever is lower than the front so does that mean that no matter what the back base always has to be thicker? Thank you
 
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If you are looking at anything that says 20MOA it means that they give you 20MAO in elevation adjustment.

The only reason for needing them would be if you were shooting at mega long ranges and ran out of internal scope adjustment.

At this point there would be 2 options. Buy a different scope with more internal adjustment, or buy the 20MAO bases.

Another option would be to shim the rear base on the current setup.

A rifle bullet is not a laser beam. It shoots in an arc.

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To get the bullet to come up, you have to lower the horizontal reticle. If the scope runs out of adjustment, you need an elevated rear to do this since the scope is out of adjustment.
 
If the rear portion of the receiver is not the same level as the front, you absolutely need a higher base there or you may be hitting about 5 feet high at 100 yards.

I use high-strength Locktite under my bases, to eliminate any chance for movement and perfect contact. For screws I use the type for screws that are not to be removed. Mine is red, but some may be green. Blue is for screws that are to be removed.

If base screws with red Loctite need to be removed, I just heat them with a torch to about 250* and the Loctite releases. That's not enough to hurt any metal, but care needs to be taken to not scorch the stock.
 
I will eventually settle on a surgeon action build some time down the road, Integral 20 MOA base... no movement included ;)
 
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