I could not get the rings to fit so I cut the bases

If you have a mill, why not make your own bases? Weavers are 45 degrees. You can use an endmill to cut both the angles on one side. Make a fixture to screw them to and use a V block in the vise. I know they are cheap, but you can make any height you want and use any material.
 
I am trying to build (5) concept rifles for hunting next month. I am working full time on this.
1) Expensive
2) Cheap [$80 so far]
3) Light [6.5 # so far]
4) Heavy
5) Factory

The expensive rifle, I had just put Burris tactical rings on Weaver bases, but it was not spendy enough. So I ordered the Seekins rings and Warne bases, just to add to the bottom line.

I have not only made Weaver bases, I have made picatinny rails out of steel welded to a Mosin receiver in the past... but I gotta stick with the theme here.



I milled out the slots to be wider [0.200"] and deeper [0.115"] with a number of passes with a 0.187" end mill.

As you can see from my sketches, the Night Force and Burris rings are not looking for trouble, but the IOR and Seekins are bad boys that want to beat up on poor little Weaver or Warne.
But EGW is a big slotted base and has no trouble with IOR or Seekins.
 

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I had that problem myself, a little while back.

The lugs on some Millet rings were too wide to fit either a factory Marlin base ("Weaver" style) or a Ranger Point Precision base ("picatinny-style"), even though the same rings were known to fit other 'picatinny' rails.

So, I reassigned the RPP base to another rifle with rings that I knew fit, tossed the piece of crap factory aluminum base in a parts box, and ordered some Warne steel bases and Leupold PRW rings.
Worked like a charm.
;)
 
I never could see the sales pitch behind steel rings and bases. Most tubes are aluminum now anyway. Just more weight to drag around. If installed properly, aluminum is fine. If you bump or hit that scope hard enough to move the base or ring, most likely you have done damage to the scope. 
 
Not only are the scopes Aluminum alloy, they are paper thin tubing.
The receivers are Steel, so there is going be dissimilar metals.
But if there is a steel receiver, then Aluminum base, then Steel rings, and then Aluminum scope, we get the two Galvanic Voltages in series.

I have some experience with these batteries in series. I tried to build the world's fastest filling bathtub with brass ball valves. The cold line was 3/4" Copper and the hot was 1/2". In order to get a ball valve with straight through diameter the same as the pipe, I had Copper, galvanized steel adapter, Copper adapter, steel adapter, Brass valve. Every time I opened the valve the first gallon of water to come out was dark red with rust. I had to tear it out and put in all non ferrous adapters. When I sold the house, the realtor said that whoever is in that tub had better be wearing a life jacket.
 
I never could see the sales pitch behind steel rings and bases. Most tubes are aluminum now anyway. Just more weight to drag around. If installed properly, aluminum is fine. If you bump or hit that scope hard enough to move the base or ring, most likely you have done damage to the scope.
Click to expand...
The particular application I mentioned had already killed an aluminum scope base through nothing more than recoil (and fewer than 50 rounds fired). The cross-lugs on the scope rings were tearing through the aluminum base. -The base being of the type with an open center and only engaging the ring cross-bolts or cross-lugs at the outer edges, rather than with full-width slots.
And, as already brought up by Clark, I discovered the beginnings of galvanic corrosion when I pulled the (steel) rings off the base.

Since I had two other types of aluminum bases on hand, I tried them, but the rings were a mismatch for slot width.

So, I went to steel-on-steel-on-steel. The only aluminum in the equation is the scope tube.
No more recoil problems (unless it kills the scope).
No more galvanic corrosion.
 
Franken,
I did a derivation a few months ago on scope bases.
It is buried in here somewhere, that I should not have oil between the base and the receiver. As we speak I am cleaning that interface with brake cleaner.

With less than 1.0 to 1.5 times the minor diameter [root] of the threads engaging the failure with too much torque will be the female threads stripping out. With more than 1.0 to 1.5 times the minor diameter of engagement, the screw will snap off. What causes the screw to snap off is mostly tension and very little torque stress. The amount of torque to snap a screw dry, must be derated to 75% with oil or grease and 50% with wax. Less friction means more tension with the same torque, and it is tension, remember, that causes the snap off. There is very little change tension in scope base screws in recoil. It is all in the pre load, operator error. Name brand US made screws are much stronger than Chinese no name.


Scope base screws are not stressed in shear, but in tension.
If my 142 gr bullet maximum acceleration is from 500 fps to 2000 fps in 0.4 ms then an 8 pound rifle will try to accelerate from 1.27 fps to 5.07 fps in 0.4 ms. This is an acceleration of 9500 ft/sec squared.
If a 2 pound scope were part of that 8 pound rifle during that acceleration the force between the rifle and the scope would be
f = m a = 2 pounds 9500 f/ss = [9500 f/ss] [2 pounds / [Gc = 32 f/ss]]= 594 pounds.

If there were 4 screws in shear that would be 148 pounds force / screw.
That screw has a 0.12" minor diameter
A = pi r r = .011 sq in
Grade 5 bolt [American cap screws] has a shear strength of 72,000 psi
Each screw would have a shear strength of 814 pounds.

But they are not in shear.
They are in tension.
Grade 5 bolts are good for 127,000 psi in tension.
Each screw is good for 1436 pounds force in tension.
They are pre loaded to about half that, making a clamping force of 700 pounds.
The coefficient of static friction between the steel scope base and the receiver is ~ 0.6
So each screw provides a static state up to 420 pounds recoil force.
4 screws 1680 pounds.
But the hard kicking lightweight rifle and heavy scope only have 594 pounds peak force between them.
1680 pounds friction is greater than 420 pounds recoil, therefor the bases stay put.
If they were to slip, the screws might see shear forces, but that would require operator error in tightening the screws.
The minor diameter of #4 screws is 0.085", so they would work too.
I am just making this stuff up, so you stop me if you find any errors.
You Google this and you tell me if anyone else on the internet has figured this out.


I think I learned something. I have long been puzzled. With my hundreds of beater rifles and those I help at the range, half the time the problem with poor groups is loose base screws. Never the ring caps or cross bolts. Why do just the base screws get loose?

https://en.wikipedia.org/wiki/Friction

Scroll down to steel on steel coefficient of static friction.
Clean and dry: 0.76 - 0.80
Lubricated: 0.16

Who would put oil on a gun?
That could cause a scope mounting failure in recoil.
Click to expand...
 
I distinctly remember one scope mounting failure years ago. A guy with a .300 mag that brought his own rings, bases, and scope. The scope was an import with a really thin tube. The tube was so thin that the rings would not hold it. The customer called up the dealer and was told to epoxy the rings to the tube. He bought a better scope instead. Yeah, mixing ferrous and non ferrous material was a gunwriter discussion for years. "Don't ever use brass shims under your bases"." Don't mix aluminum and steel components." Yeah, yeah, yeah. I made a LOT of aluminum bases, rings, and one piece ring/base set ups from 7075 aluminum. Did you ever hear of paint? I would like to see just one anodized base that had a reaction with a steel receiver. Cheap is cheap. A cheaply produced steel set up is as bad as a cheaply made aluminum set up.
 
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Neither Clark, nor I said aluminum was worthless; or that there was no legitimate use for it.
But in some applications, it is not the best choice of material.

--

Paint chips.
Aluminum abrades.

Anodized aluminum is like case-hardened steel: Once you get through the hardened shell, it's a whole different animal.

Either way... the aluminum base was already damaged (and raw aluminum exposed). What's the point in painting a base that's already failing in the application, just to watch it do the same thing - but this time, with fresh paint?


As I've mentioned here (and elsewhere) before... I spent the prime of my life working on aircraft - primarily helicopters operating near or over salt water. I spent a great deal of time inspecting for, identifying, stopping, repairing, and preventing corrosion of all types.
Corrosion is my enemy (even with salt water being out of the picture).

I already avoid aluminum scope rings.
If I'm presented with a situation where I have a choice between steel and aluminum scope bases, I'm going to opt for steel. A) Because I hate corrosion; it happens when you least expect it; and galvanic corrosion can be exceptionally destructive when not discovered early. B) Because an extra ounce (or less) of weight is worth having the better material.
 
Why is it better? I remember seeing an add for name brand bases and rings mentioning the use of "Sturdy 12L14 material" in their construction. That is kind of like the Junkoloy of the steel world. I have pulled junk rifles apart that I bought for parts and under the aluminum bases was blued steel on the receiver. If I worried about silly things like that I would never have had anything to do with an AR style rifle. 
 
12L14?
I feel like James Garner in 1969 Support Your Local Sheriff, when the brothel is hit with cannon fire, "Some of those girls are the closest friends I got."

I have pieces of 12L14 in all diameters of hex, in case I want to make something.
 
Not totally worthless, but if you are worried about recoil snapping off a set of rings, move up to 4140/4142. If that seems dicey, maybe safety chains like on a trailer. I don't see how paint can chip off under a ring base,BUT, I have no idea what some people do to their equipment. I have seen some truly weird, off the wall stuff.
 
My brother found a deal on 4140 and I have >100 pounds of it.
When I drill a hole in it, if I do not have coolant, the bit 4140 gets hot, gets hard, tool gets dull, and now I have to find carbide drill to cut through the hard spot.

So 12L14, 1010, and 1018 are easy. 4140 and some of the stainless I have are hard.

The 6160 T6 Aluminum alloy that is so common will gum up end mills if I don't run it fast and noisy.

I don't like metals that are hard to cut.
I like metals that cut themselves.
 
Try some 7075. It is the toughest aluminum alloy before any type of treatment. You drop a bar of that on the floor and it rings. My GranMa used to say"If you take moose crap and fry it, you have fried moose crap."
 
I made two dual diameter slave pins for marking magazine cutout for a V block today out of ......12L14.

Then I had sticky Alum problems. Finally I did shallow cuts like open pit mining.
 

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I weighed them with scopes

1) Expensive rifle, $3300 so far
Pre 64 M70 25-06 Shilen stainless select match stainless 257 #3 taper 8" twist 25" barrel painted black with Aluma hyde II
9.2 pounds with NXS scope

2) Cheap rifle $80 so far
Type 99 Arisaka 308 American Springfield WWII surplus 20" chrome moly barrel
7.8 pounds with Simmons scope

3) Lite rifle
Rem 700 SA 6mmBR Stainless Super Match. 1-8" Twist. 6mm. Polygonal rifling. 28" long. Factory Remington Mountain Rifle Contour painted black with Aluma hyde II
7 pounds with Leupold 3x9 CDS

4) Heavy rifle
Rem 700 LA 7mmRemMag Benchmark #5 taper 9" twist 5 groove Ratchet rifling 28" barrel painted black with Aluma Hyde II
13.5 pounds with IOR 10x56 scope

5) Factory rifle
Browning B78 25-06 original 1994 Japanese barrel 25" chrome moly
8.8 pounds with Leupold 3.5x10 CDS scope
Not completely factory, I made a double steel pillar fore end so I can attach a bipod way out there.
 
I have 5 tags, and two ranches to choose from.

My guess is at least one can keep it in the kill zone at 500 yards and probably most of them at 400 yards.

I have shot the last 9 animals from right next to the truck and most at less than 250 yards.

So I could probably live with any, but I am going to try to get in 2 weeks of long range target practice, reloading in my camper.
 
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