Question concerning scope height

[Guest Plainsman]

I previously had my Savage 10fp with a Millett 4-16x56 set up on a 0moa two piece Warne mount in which I used Warne Maxima high rings. I recently installed an EGW 20moa one piece rail so I could enable the scope adjustment to shoot 1000yrds if I ever got the chance. I've found that the new rail actually places the scope higher and I'm questioning buying some lower rings. On my math (which is not my favorite subject) I have .375" clearance currently. My high rings measure .525" from base of ring to bottom of scope tube. I believe that I could clear the low rings which measure .25" from base of ring to bottom of scope tube and still have enough clearance for the scope cover (.525-.25=.275 leaving .1" clearance). I understand it is best to mount the scope as low as possible without any contact with the barrel.

Will lowering the scope this .25" make any difference as far as accuracy or would it be a simple asthetic fix? Bottom line: is it worth it?

Here is the scope clearance with the high rings. Sorry for the crappy cell phone picture.

[JeffsSig]

Will lowering the scope this .25" make any difference as far as accuracy or would it be a simple asthetic fix?

They way I see it and I may not be right:

It will not change accuracy per say. It will change the point of aim at a given distance over the original setup.

[mikegideon]

If the center of your scope is 2" above the center of the bore, it will shoot 2" low at the muzzle.

Here are the trajectories of a .223, both with a 200 yard zero. One is with the scope mounted 1.5" above the bore, and one with the scope 2" above the bore.

[Guest Plainsman]

So is my scope currently too high, or not? Should I change to lower rings?

[mikegideon]

So is my scope currently too high, or not? Should I change to lower rings?

I wouldn't change, unless you're trying shoot dimes inside of 25 yards, and don't want to correct for the trajectory. You have a rainbow trajectory with any gun, and it's only going to be dead accurate at two places.

Most of my scopes are as low as I can get them, but it's more about preference. Doesn't affect "accuracy", just the relationship between line of sight and trajectory. If you zero the scope at 200 yards (or any other range), mounting height doesn't matter at that range.

[Guest gcrookston]

the ideal is to have your C to C as close as possible. Center of your scope to the Center of your bore. Based upon the picture you posted, you've some yardage to go to make the optimal C to C. You don't want the bell of your scope touching your barrel, but you do want it as close as you can get without touching...

I have found "the math" from lowering my optics towards a better CtoC minimal at worst. The dope on my m1a from A.R.M.S. to the current Mk4 mounts where a 1/4" and the deviance was negligible for my book, even to 1,000 yrds.

Where it comes into play is cant, reducing and eliminating cant is the goal of CtoC.

like this:

was like this:

shoots like this with new rings:

As you can see, the up-down was negligible. These shots were done zeroing the new rings at 100 yrds, Counter clockwise from lower left to upper RH adjusting 2 clicks (1/2 MAO), until zeroed.

The cantered angle is all I worry about, and this is much reduced by a CtoC close measure.

Edited April 3, 2010 by gcrookston

[Guest gcrookston]

I wouldn't change, unless you're trying shoot dimes inside of 25 yards, and don't want to correct for the trajectory. You have a rainbow trajectory with any gun, and it's only going to be dead accurate at two places.

.

I like shooting dimes at 100, 200, 300 and 500 yrds. Since I can't see them at 1,000 yrds, I'll just aim for the head of the holder...

Edited April 3, 2010 by gcrookston

[Guest Plainsman]

I believe I'll order the lows...hope my math was right!

[Guest gcrookston]

You won't notice improved accuracy, but you will see a reduction in the influence of your rifle's tilt or "cant". Especially if you are shooting distance -- beyond 300 yrds, a little lean to the left or to the right can mean the difference between hitting the target and being inches or feet off from it... By getting the CtoC (Center of Scope to Center of Bore), as close as possible, it reduces the influence of canting. Some distance shooters install a leveling bubble on top of their optics to make certain their cant is zero.

I haven't gone to that degree yet, as I think I know when I'm on the level... Like now.

Get your scope as low as possible without touching, you'll benefit from it. Trust me, I may not know much, but I know optics....

Edited April 3, 2010 by gcrookston

[mikegideon]

You won't notice improved accuracy, but you will see a reduction in the influence of your rifle's tilt or "cant". Especially if you are shooting distance -- beyond 300 yrds, a little lean to the left or to the right can mean the difference between hitting the target and being inches or feet off from it... By getting the CtoC (Center of Scope to Center of Bore), as close as possible, it reduces the influence of canting. Some distance shooters install a leveling bubble on top of their optics to make certain their cant is zero.

I haven't gone to that degree yet, as I think I know when I'm on the level... Like now.

Get your scope as low as possible without touching, you'll benefit from it. Trust me, I may not know much, but I know optics....

You're right, and I didn't think about that. Thanks for setting me straight

[mikegideon]

Double post

Edited April 3, 2010 by mikegideon
Double post from server glitch

[Guest gcrookston]

You're right, and I didn't think about that. Thanks for setting me straight

isn't that the only reason I would be here?

I've been shooting distance alot lately 300yrd to 1,200yrd with my SASS, bolt gun 7.62 and M1a. Eliminating cant is the biggest issue I've had to address.

Edited April 3, 2010 by gcrookston

[Guest Plainsman]

Yes, canting was the one main issue that I was reading about--at least that influenced the trajectory. Using the word "accuracy" in my OP was probably not the best of terms---and I'm glad that ya'll caught on to what I was meaning. I appreciate the response.

[mikegideon]

isn't that the only reason I would be here?

I've been shooting distance alot lately 300yrd to 1,200yrd with my SASS, bolt gun 7.62 and M1a. Eliminating cant is the biggest issue I've had to address.

That explains that picture I saw of an Iphone bracketed to the side of a rifle.

[Guest gcrookston]

That explains that picture I saw of an Iphone bracketed to the side of a rifle.

Haha, Hardly,

SASS

trying to find 300 yards...

Note the 852 ammo... hate to waste it by missing a shot...

Edited April 3, 2010 by gcrookston

[mikegideon]

Haha, Hardly,

SASS

Ah... working off the top line of the berm. The picture I saw was a tactical rifle. Iphone running ballistics software. There's a built-in level in the iphone. I'll try to dig up the pic

[mikegideon]

Here it is...

[Guest gcrookston]

WooWhooo, I need me one of these, is this verizon or AT&T???

[mikegideon]

Unfortunately, just AT&T for now. i have a couple of ballistics aps loaded on mine, one with a JBM engine and a decent library. 20 bucks for the ap

[gregintenn]

In addition to reducing the effects of canting, the closer to the bore you get the scope, the better the cheek weld you get against the stock. That makes shooting more comfortable and repeatability easier. Both of these result in better shooting. I'll get flamed for this but; scopes aren't penises....bigger isn't always better.

[Guest Plainsman]

In addition to reducing the effects of canting, the closer to the bore you get the scope, the better the cheek weld you get against the stock. That makes shooting more comfortable and repeatability easier. Both of these result in better shooting. I'll get flamed for this but; scopes aren't penises....bigger isn't always better.

I agree completely. I already had to get a beartooth comb raising kit for the original setup, but had to go up to the 1/4" pad with the new rail. Although the cheek weld was ok, I believe now that the pros for having lower rings for a lower overall setup way outweigh keeping the setup as it stands now. And as far as "bigger being better" I again agree. I got this optic because of the amazing deal I got on it, which I just couldn't pass up.

I've got a Rem700 build coming up sometime or another that I will not be messing with any more 56mm objectives! Still now sure where to go with the 700 build as its chambered for .270. Although I've heard that the .270 has reached out and touched a few things itself.

I wonder if that iphone works best with the recoil if its in the Magpul iphone case?!

[mikegideon]

I agree completely. I already had to get a beartooth comb raising kit for the original setup, but had to go up to the 1/4" pad with the new rail. Although the cheek weld was ok, I believe now that the pros for having lower rings for a lower overall setup way outweigh keeping the setup as it stands now. And as far as "bigger being better" I again agree. I got this optic because of the amazing deal I got on it, which I just couldn't pass up.

I've got a Rem700 build coming up sometime or another that I will not be messing with any more 56mm objectives! Still now sure where to go with the 700 build as its chambered for .270. Although I've heard that the .270 has reached out and touched a few things itself.

I wonder if that iphone works best with the recoil if its in the Magpul iphone case?!

The iphone is pretty tough

[Guest gcrookston]

you'll definitely need the iphone for a 270. Think 30-30 on pepsid-ac. A less than stellar calibre...

What were we talking about again? I forgot.

[Guest Plainsman]

What were we talking about again? I forgot.

I hijacked my own thread. Low rings are on the way...I"ll update when the scope sits low.

[mikegideon]

you'll definitely need the iphone for a 270. Think 30-30 on pepsid-ac. A less than stellar calibre...

What were we talking about again? I forgot.

The .270 ain't so bad, at least not compared to its parent, the 30-06. Red trace is the .270. Wind drift is worse, but it's flatter. I tried to pick similar BC's

EDIT: Wind drift is not worse once I equalized the wind speed in both traces.

Edited April 4, 2010 by mikegideon