Rifle Scopes MOA elevated base?

balls2elwall

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I've been shooting and hunting for years but now as i try to get more accurate and practicing to compete i seem to have all these questions i never knew existed before. im in the market for a decent to nice scope mount and rings for my remington 700 BDL .308. while shopping for the scope base i keep coming across different "elevated" scope bases. my local gun shop only carries the cheap weaver alluminum ones and now i need help.... lots of help! can anyone help me better understand.
 

dareposte

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Re: MOA elevated base?

The "Elevated" bases are machined at a small angle, so your scope points slightly downhill compared to the bore. This lets you get more useful adjustment out of your scope.

For example, if your scope has 50 moa of total adjustment in elevation it would theoretically zero out in the center of that range, leaving only 25 moa of "up" adjustment.

Put the same scope on a 20 moa base, and now it zeros out near the bottom of its adjustment range, leaving 55 moa of "up" elevation.

You can accomplish the same thing by shimming the back-side of a one piece base like the leupold twist-in types. I've done both and for the hunting rifles I shim Leupold twist-ins since they're lightweight and cheaper, but my serious long range rifles get steel NightForce canted bases and IOR steel rings.
 

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Re: MOA elevated base?

PS -

You don't necessarily need a canted/elevated base unless your scope can't adjust to the range you want to shoot. Most popular hunting style scopes only have 50-60 moa of total adjustment, so to get them to 1000 yards you need a canted base.

For a Rem700 you can check out the EGW bases, they run about $40 for a base and are the lowest cost viable option. Going up in price from them you can get into a bunch of nice bases from Seekins, NightForce, IOR, Badger, etc for the $100 range.
 

balls2elwall

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Re: MOA elevated base?

thanks alot that answers all of my questions perfectly. ive been looking at badger and seekins bases they seem to be the best for my price range.
 

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Re: MOA elevated base?

Before you buy, make sure to match the base to your scope. It wouldn't make sense to put a 40 moa base on your rifle if your scope only has 50 moa of total adjustment. You'd never get it to zero at 100 yards.

The general rule of thumb is to not get a base higher than 40% of your adjustment range for the scope you want to use. If your scope has 50 moa total adjustment, a 20 moa base is max for you. If it has 100 moa of elevation, you can get away with a 40 moa base. But its best to measure and check before you order just to be safe.
 

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Re: MOA elevated base?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: balls2elwall</div><div class="ubbcode-body">oh one more question in your opinion should i get picatiny style? </div></div>

It really depends on what you're wanting to do. The big advantage of Picatinny style in my opinion is that you can swap one expensive scope between several rifles with the same bases.

For example one of the AMU guys always puts the same NF base on his rifles, and just swaps his favorite scope between whichever one he is shooting. He claims it repeats to 1/2 MOA on every rifle, but of course each rifle has a different "zero" for the scope in windage and elevation. I guess he doesn't mind keeping track of that and he gets to shoot enough to always have the settings fresh in his head.

The Picatinny rails tend to raise the scope up higher over the bore, and are heavier than other types. But for long actions the extra strength of the base can really stiffen the action up which is a good thing.

Like I said, for my hunting rifles I prefer a lighter weight base that sits lower over the bore. I use the Leupold twist-in bases and just shim them to get the range I want. I'm also using lightweight scopes (Nikon or Sightron, usually < 1 lb) so I don't worry about the recoil stressing the rings too much. For range rifles or anything going over 800 yards or with a scope over 20 oz weight, I use a NF picatinny steel rail with recoil lug, and steel rings. Both systems work well for me and are reliable and accurate when set up properly.

One other thing I don't like about the picatinny rails is that they can cover a substantial portion of the ejection port, making it hard to load or unload the rifle sometimes.
 

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Re: MOA elevated base?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: balls2elwall</div><div class="ubbcode-body">aluminum or steel? </div></div>

Aluminum or steel, doesn't seem to matter if you get a good quality base. I use steel for my Picatinny bases because I have heavier scopes on my longer range rifles and they tend to have stronger recoil (338 Edge, 300WM). I like the weight of steel bases and rings to help tame the recoil a bit as well as stiffen up the long action some.

If you're building a hunting rifle or want to watch the weight of the build, I wouldn't see any problem going to an aluminum base. On a magnum rifle you might want one with a recoil lug just to be safe.
 

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Re: MOA elevated base?

If you go with a steel base you should be careful installing it, if the rifle action isn't true the base can actually be so rigid that it pulls the receiver action into a torque.

Bed the base with JB weld or Devcon or one of the other bedding compounds, and lightly snug the screws while it sets. Dont forget to use release agent on the action. If you're sure you wont be changing bases you can glue it on with rearview mirror adhesive when its done.
 

balls2elwall

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Re: MOA elevated base?

im shooting a short action .308 i think im going to opt to go with aluminum piccatany base so i can switch it into a different rifle when i get more experienced. i also shoot a nikon 4-12x44 scope so weight isnt an issue. thanks to all your sound advice im going to save on the base and spend the money on rings and ammo.
 

The Shottist

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Re: MOA elevated base?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: balls2elwall</div><div class="ubbcode-body">aluminum or steel? </div></div>I pondered the same thing this week. After reading Murphy's site and talking to him, I am convinced that steel is a better choice due to excessive expansion with Aluminum bases.
Read this:
http://www.murphyprecision.com/Page/Titanium_Benefits

here is the correct procedure for bedding a base:
http://www.murphyprecision.com/Page/Scope_Base_Bedding

His prices are excellent and he is very helpful on the phone.
He is making a custom base for me at the same cost as his stock base.