what makes a scope mount rail better?

[trickyric]

I was wondering why a scope mount rail made of aluminum for mounting a scope is $120 from Leupold or $50 from Millett?
Is one better and if so what makes it better?
Does it effect accuracy or is it just about the brand?

 

[creeper1956]

Materials (alloy grade), heat treat, fit, machining, type of anodize or coating. You don't say which rails exactly, or if they are Weaver or 1913 mil spec, so there's nothing to review, but Millet is on the lower end of the quality scale while Leupold is on the upper mid end of the scale... and yes, you are paying a few bucks extra for the Leupold brand.

Again, don't know what you have, but there are lots of other rails on the market. EGW and Badger to name a few of those I've used with excellent results.

 

[1911 guy]

As a machinist, there are some things I'd consider. Is it machined flat and square? How close are the acceptable tolerances? Are the screw holes in alignment? Are they on centerline?

This stuff gets important when you consider that a small error on top of your rifle is a big error at 100 or more yards.

I'd look into those more than price. There are quite a few companies over the years that have offered equal or superior products for less money.

 

[WardenWolf]

In all honesty, not much. One hunk of stainless steel or aluminum is not going to be substantially better than another, and modern production techniques are more than adequate enough for even cheaper companies to produce rails that are functionally identical to more expensive ones. Unless the alloy is absolute crap such that it can't stay rigid with the recoil of the gun, they're all pretty much the same. Even Chinese brands like Leapers / UTG will do the job just fine.

The same goes for scope rings, too. The $25 Warne rings I put on my Mauser are just as solid as an $80 set of Leupolds, and are actually inherently stronger due to their design.

 

[trickyric]

I have a Leupold rail on my Remington 700. I was at the store and I noticed the Millet rail for the same scope mount was $50 and I paid $120 for mine.
I got to wondering "it's a piece of aircraft grade aluminum. It doesn't have any moving parts or sliding function. It's gets locked down on the action and rings get screwed to it.
So was I an idiot for wasting $70 bucks on a name or was there really something better with the Leupold I purchased.

 

[CraigC]

Materials (alloy grade), heat treat, fit, machining, type of anodize or coating. You don't say which rails exactly, or if they are Weaver or 1913 mil spec, so there's nothing to review, but Millet is on the lower end of the quality scale while Leupold is on the upper mid end of the scale... and yes, you are paying a few bucks extra for the Leupold brand.

Exactly! All aluminum is not created equal. No, they are absolutely not all the same. Machined 6061-T6 is better than a cheap extrusion and 7075 is better than that. Finishes are not equal either. Compare the cheap finish on a $5 Weaver base to that of a real anodized hardcoat. You just have to decide what's important to you and what you're willing to pay extra for.

 

[hardluk1]

And if avalible the weaver or utg will do all you need just as well as a costier model. Higher cost many times is just because for the advertizing hype. Maybe the "look" well make a difference on certan firearms maybe some feels brand A is simple better because of the look, reality is many of the lower cost items will work just as well.

 

[k_dawg]

My experience has been that the 'fit' is often subpar on the cheaper ones. That can often be compensated by cranking down on the bolts. However, that can introduce problems in the optics.

A proper fit will allow one to mount two mounts with perfect alignment, even without having the scope installed. It should NOT be using the scope itself to pull the mounts into alignment. There are installation tools to verify positive alignment.



Whether or not such precision is required depends on your application.

 

[MachIVshooter]

The same goes for scope rings, too. The $25 Warne rings I put on my Mauser are just as solid as an $80 set of Leupolds, and are actually inherently stronger due to their design.

I beg to differ on rings.

For many applications, cheap rings that leave a gap between halves or flex a bit around the scope body are not problematic. But on a heavy recoiling rifle, crappy rings may not hold the scope in place, or could cause damage even to a quality scope.

Also, there's

It should NOT be using the scope itself to pull the mounts into alignment.

Depending on what gun, what scope and how rigid the rings are, this could damage a scope quickly, or over time.

 

[WardenWolf]

MachIVshooter, the Warne rings actually are split into two complete halves, rather than having separate mounting for the base and the upper ring half. You have to mount the scope at the same time as the base. There are 4 screws, and they all work together to clamp both the mount to the rail and the scope in the rings. It's inherently better because it provides a tighter fit all around and there's fewer parts to move.

 

[MachIVshooter]

MachIVshooter, the Warne rings actually are split into two complete halves, rather than having separate mounting for the base and the upper ring half. You have to mount the scope at the same time as the base. There are 4 screws, and they all work together to clamp both the mount to the rail and the scope in the rings. It's inherently better because it provides a tighter fit all around and there's fewer parts to move.

Yeah.............those are the worst kind, IMO. Really easy to have too much or too little pressure on either the scope body or the rail with that design. They are made that way because it's cheaper.

If they work for you, great. But I won't cheap out on rings with a $900 rifle, a $600 scope and a cartridge that recoils in excess of 50 ft/lbs. I use quality bases, quality rings, I lap them, and I properly align them.

 

[trickyric]

Interesting stuff here.
So if the rails are both T6 aluminum, CNC milled and anodized are they basically both as effective for the job at hand?

 

[MachIVshooter]

So if the rails are both T6 aluminum, CNC milled and anodized are they basically both as effective for the job at hand?

T6 is a suffix that indicates the type of tempering. What comes before that matters, because it is the actual alloy.

http://www.keytometals.com/page.aspx?ID=AluminumGrades&LN=EN

http://www.engineersedge.com/aluminum_tempers.htm

For example, 6061-T6 and 7075-T6 have the same tempering, but 7075 is about twice as strong.

And then there is silicon content (Hypoeutectic, eutectic, and hypereutectic alloys). The silicon content affects the melting point and thermal expansion coefficient of the alloy inversely to it's brittleness and ductility.

http://www.keytometals.com/Article80.htm

Metallurgy is anything but a simple science. Do your homework before you determine that one alloy is "just as good" as another for a given purpose.

 

[creeper1956]

So if the rails are both T6 aluminum, CNC milled and anodized are they basically both as effective for the job at hand?

Still no.

MachIVshooter has the aluminum covered, so I'll toss in a bit of CNC and anodize.

"CNC milled" doesn't mean quality either. It doesn't tell you what the tolerances are held to, how often the cutting tools are inspected and replaced and so on. Closer tolerance = tooling & time. More tooling & time = greater cost. Simple huh?

There are different types of anodizing. Type I is chromic based, primarily cosmetic in nature... this is often the colored stuff you see on 2 dollar mini-carabiners at the hardware store. Corrosion resistance is OK and although harder than the aluminum base, is thin and easily scratched. Type II is sulfuric based and is more durable than type I, and what you see on fair to good tools, sporting goods (better carabiners ).
Type III or "hard coat" is also sulfuric based and is substantially harder than the aluminum substrate. This is what you see on quality firearms with aluminum frames and/or receivers... and carabiners you'd stake your life on. With an average Rockwell C rating of 65, its very wear, corrosion and abrasion resistant. It even has a pretty good lubricity value.

My personal and simple rule of thumb for guns and gun related stuff. Buy the best you can afford... and by afford I mean, what ever you initially thought you wanted to spend... times 2 or more.

 

[trickyric]

So without the benefit of a metallurgy degree the Leupold would be a much better rail?
as far as shooting how does it effect accuracy?
What should a person be looking for as far as specifications when shopping for rails?

I already bought the Leupold but I still don't get what the actual effect on performance the extra money provides.

 

[k_dawg]

MachIVshooter, the Warne rings actually are split into two complete halves, rather than having separate mounting for the base and the upper ring half. You have to mount the scope at the same time as the base. There are 4 screws, and they all work together to clamp both the mount to the rail and the scope in the rings. It's inherently better because it provides a tighter fit all around and there's fewer parts to move.

What type of tolerance do you think you'll measure with the Brownell's jig that I posted?

You need a VERY accurate fit to have zero deflection with those style of mounts. If you are not, you are torqueing/stressing the scope body and probably the optics.

Now, it may not matter to the end users. But that is a different statement.

 

[Walkalong]

Using a ring alignment tool to see if rings are aligned well can open your eyes. As in, gee that's bad. I threw away a set of rings not long ago they were so bad.

And cheap rails are not as good as better rails. Good enough? Yea, for some things.

 

[holdencm9]

I think the answer is, for most people, nothing. But the same could be said of any product, firearms-related or not. Some people at the higher tiers of skill will be limited by low-cost options, that will be perfectly fine for 99% of people. There is a reason costs vary so much. Not everyone needs super-high-end.

 

[trickyric]

So what I am gathering from the responses if the Aluminum is not foil and the part was not milled with a file and chisel there could be issues with lining up the rings perfectly that may or may not effect anything as for as shooting accuracy?
The original question of what is the performance difference doesn't seem to have been answered.
So I am thinking that from a technicians standpoint the lines would not be as clean as they could be but if the rail is made decently with today's technology it may not be perfectly pleasing to the machinist but would preform it's task without issues on the actual accuracy of the firearm.

 

[holdencm9]

tricky, like I said, it is like anything else.

Bikes for instance... I wanted a road bike, for casual riding (mostly on bike paths, incidentally) to get some exercise and recreation with the wife...but the guy kept trying to sell me on some high-end carbon forks and fancy seat and these clip-in pedals that weigh 2 oz less than the ones that came with the bike. I was like, okay, I have no doubt that those things are BETTER, but do I NEED them?

For most hunting applications, under 200 yards and minute-of-deer, I think you would be fine with most any rail/ring/optic. If you are shooting twice that distance and are disappointed with 2" groups, you may be disappointed with the cheaper hardware.

 

[trickyric]

Ok,
I get the bike reference. On a bike a more secure foot rest, polymer parts that take weight off the bike and other mechanical parts that actually move or have a moving function can effect the performance.
But how does a rail that does not move do that?

 

[Deus Machina]

I get the bike reference. On a bike a more secure foot rest, polymer parts that take weight off the bike and other mechanical parts that actually move or have a moving function can effect the performance.
But how does a rail that does not move do that?

Fit and finish, and that it may or may not actually move.

A better fit means it's more in alignment, and won't make otherwise perfect rings apply a sideways pressure on the scope.

On the bottom side, let's say a ring is made to fit a rifle with a 1" diameter receiver. Brand A could keep a tolerance of +0.0/-0.002. Not uncommon for modern, quality CNC machining. The + means that the radius will be no more than 1", and the minus that it could be 0.998". This will have a ring that either fits perfectly, or contacts at two points--and possibly force-fits--and is thus stable.
Brand B may run a tolerance of +0.003/-0.005. A 0.995" will probably work just fine, but a mount that contacts at just the edges is more likely to bend in one direction more than the other, and a 1.003" ring will contact only on a line down the center and would allow the scope to rock slightly under pressure.

Aside from that, 7075 aluminum isn't likely to flex under any normal circumstance. Neither is 6061, but it won't be as tough. 2021, on the other hand, is sometimes used by cheaper companies because it's easier to machine, but it's much softer than many other alloys. This means it will scratch easier, screw holes are more likely to strip, and it's likely to flex when you fire.

TL;DR version: it's not that scope mounts don't move, it's that they're not supposed to, and better ones keep it that way.

 

[MachIVshooter]

But how does a rail that does not move do that?

You'd be amazed how much "rigid" things flex under the kind of shock and strain present when a firearm cartridge discharges.

Go to youtube and search some slow motion footage of guns firing. There's one in particular of a full auto AK; The whole gun looks like jello wiggling at a few thousand frames per second.

 

[trickyric]

this has been a learning experience!

 

[hentown]

Here's another lesson for you. A $300 AR free float tube by LaRue won't be any more rigid, durable, or make your AR any more accurate than will a $70 DPMS or a $100 YHM tube.

I doubt that a $150 LaRue rail will be any more rigid, finished any better, blah, blah, blah, than a $35 YHM rail.