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multiple68 wrote:As an update...I was finally able to get my groups down to sub MOA. Part of it was definitely the ammo, but I think I also needed to just get more rounds through this particular rifle.

I did "shoot the box" as was suggested by TAM, and got nice results. This was after I got shots placed in the middle of the target.

Got a deer with this rifle a few weeks ago...right through the lungs where I aimed.

Excellent! Glad you got good results, and bagged a deer to boot. Patience pays off, doesn't it?

multiple68 wrote:

The Annoyed Man wrote:
1. Exactly what model of Leupold scope are you using?

2. How far apart were the two groups, center to center?

3. How many clicks on each of the adjuster knobs did it take to move the second group that far from the first?

Also, one last thing to consider......are you using the scope cranked all the way up to full magnification, and what power of magnification is that? (I'm thinking of parallax errors here....)

1. Leupold VX-2 3-9x40 with the duplex reticle and 1/4 moa finger click adjusters
2. The two groups center to center were about 3 or 4"...both 1.5-2" from bulls eye.
3. I dont remember for sure, but about 10-15
4. Full magnification yes, shooting off a tripod

Will probably do some shooting this weekend...I will try to tap the scope between adjustments and try the over adjust and come back down trick.

One thing you can do is to try and "shoot the box," but that should come after you get the scope zeroed, not before.

OK, so assuming your scope is properly mounted and secured, and assuming you are shooting at an actual measured 100 yards (not just guesstimated), with 1/4 MOA adjustments, each click should move the point of impact 1/4". One MOA at 100 yards is 1". So 1/4 MOA at 100 yards is 1/4".

FIRST: use a centerfire rifle sighting in target similar to this one:

It doesn't have to be exactly this one, but there are several that are very much like this, and that's what you want. The small squares with the narrow lines are 1" on a side, so it makes it relatively easy to measure through the scope exactly how far up/down and left/right your fall of shot is away from the bullseye. This is important because your scope has a duplex reticle, and that particular kind of reticle is lacks any kind of stadia lines which provide you some kind of measuring capability built into the reticle.

Milling reticle on left, duplex on the right:


SECOND: be sure to keep track of exactly how many clicks of windage (left or right) you crank into the side turret, and how many clicks of elevation (up or down) you crank into the top turret. Here's why: if the top left group you mentioned before was centered 2" above and to the left of the bullseye, then 8 clicks to the right, and 8 clicks down should center the group on the bullseye.

THIRD: A) fire one group of 3 to 4 rounds (I use 4), slowly, giving at least a couple of minutes between shots. You are trying to keep the barrel from heating up too fast. Your first, cold-bore shot represents your rifle's true accuracy, since in the field, whether you are hunting, plinking, target shooting, or sniping (especially hunting or sniping) the first round is the one that has to count. B) let your barrel cool a bit after firing the string, and use the time to count how many squares or fraction of squares you are from the bullseye. Convert those squares to inches, and convert those inches to clicks. Adjust your scope accordingly.

For instance, if your point of impact (POI) is 1.5 squares high and 2.75 squares left of point of aim (POA), then your POI was 1.5 inches high and 2.75" left.

FOURTH: A) turn your elevation knob 6 clicks (6 X 1/4" = 1.5") in the down direction to move your POI down 1.5"; B) turn your windage knob 11 clicks (11 X 1/4" = 2.75") to the right to move your POI 2.75" to the right; C) fire another slow 3-4 round string.

FIFTH: observe the center of the POI for your second string. How far off of the bullseye is it? It should be spot on, but it might be a 1/4" or so off in either plane. That is fairly insignificant, and I would be happy with that kind of deviation. However, if it is not close enough, repeat steps 3 and 4 until you've got it where you want it. RESIST CHASING THE ZERO to gain that last 1/8-1/4" onto the bullseye. It will never be perfect, and if you start making too many adjustments, you may lose sight of your zero. Once you find your zero, let the barrel cool, and then shoot another group to confirm the zero.

LAST: only after you have zeroed, "shoot the box" using a fresh target. Make no other adjustments than the ones listed here, and let your barrel cool a bit between each group fired. Here's how to do it.

1. confirm the zero shooting a group into the bullseye.

2. move your POI 12 clicks to the right and 12 clicks up. Keeping your crosshairs on the bullseye, fire a group. It should land exactly 3 inches high and 3" to the right of your bullseye. Make no other corrections if it does not, but make a note of how far off it is.

3. move your POI 24 clicks to the left. Keeping your crosshairs on the bullseye, fire another group. It should land exactly 3" high and 3" to the left of your bullseye. Make no other corrections, but make a note of how far off it is.

4. move your POI 24 clicks down. Keeping your crosshairs on the bullseye, fire another group. It should land exactly 3" below and 3" to the left of your bullseye. Make no other corrections, but make a note of how far off it is.

5. move your POI 24" clicks to the right. Keeping your crosshairs on the bullseye, fire another group. It should land exactly 3" below and 3" to the right of your bullseye. Make no other adjustments, but make a note of how far off it is.

6. move your POI 12 clicks to the left and 12 clicks up. Keeping your crosshairs on the bullseye, fire your last group. It should land exactly on the bullseye. Make a note of how far off it is. If it is significantly off, rezero, then confirm your zero with a second group.

look at your notes. You might make a range card which tells you how far off your clicks are from what you expected to produce, and you can use that information when making adjustments in the field.

Once you've finished shooting the box, make sure you set your adjustment knob indicators to "zero" if they have that feature, so that you'll know you are zeroed the next time you shoot the rifle.

multiple68 wrote:So was able to try the rifle out with the new Leupold scope today shooting Federal Gold Medal 168 Grain Match BTHP. I was finally getting some decent groups...anywhere from .45" to .85" at 100 yards depending on the shooter.

Now another issue. The groups were decent, but it was shooting a little high and left. We would adjust the windage, but it didnt really seem to make much of a difference, despite pretty drastic changes. Then all of a sudden it would be shooting low and right. It never seemed to settle where we wanted it despite having tight groups between scope adjustments.

Could this be another issue (sticking turrets?), with a now different scope, or do I just need to put more rounds through the rifle? Overall, it will be fine for the hunting I will be doing this season, but I know this rifle is capable of more.

Could be that the scope isn't level, like Mojo said. It could also simply be a factor of how large the adjustment increments are in the knobs at a given range. You mention a Leupold, but which Leupold, with which reticle and which knobs?

A rifle like an SPS wants a tactical scope with some sort of milling reticle. It wants a scope where the adjustment increments match the stadia on the reticle. If you have Mil-dot reticle, then you want a scope with .1 mil adjustment increments on the knob. If you've got a reticle with stadia lines in MOA, then you want adjusters that click in MOA. Not all scopes, even some very expensive scopes, are set up that way. But the ones that are set up that way are MUCH easier to zero (see below).

A scope with adjusters that match the reticle will never change the number of clicks necessary to move POA at any given distance. Example: My tactical scopes use .1 mil adjusters and mil reticles. I put the crosshairs on the target and fire. Bullet impact lands .2 mil left, and .3 mil high, I crank in 2 clicks right and 3 clicks down, and the second shot should land right on the bullseye. And this works whether you're at 100 yards, 368 yards, 894 yards, or 1,132 yards. No fuss, no muss. Ditto for a scope with 1/4 MOA adjusters, and 1/4 MOA stadia lines on the reticle.

ALSO.... How much is "a little high and left," and how much is "low and right?" EXAMPLE: if your rifle has 1/4 MOA adjusters at 100 yards (the MOA value will be different at different distances.....1/4 MOA at 100 yards = 1/2 MOA at 50 yards, etc.), then each click of windage or elevation will move the bullet impact 1/4" left, right, up, or down, depending on which knob is being turned in in what direction. So you haven't told us how far the bullet impact travelled to get from "a little high and left" to "low and right." If that distance from the center of the first group to the center of the second group is 1/2", then you're about as close to spot on as you're going to get it because the minuteness of the adjustment necessary is outside the capability of the adjusters to deliver. If your adjusters were 1/4 MOA at 100 yards and those two groups were only 1/2" apart, then you would have had to use 2 clicks down and two clicks right to move the group center that half inch right and half inch down. HOWEVER, if the first group is 2-3" high and to the left, and the second group is 2-3" low and to the right, that's a 4-6" transition in both planes, and that is really significant. If that's the case, then something ain't right, because even a cheap Leupold should be better than that.

SO.... if you want a more specific answer to your question, please provide these three pieces of information:

1. Exactly what model of Leupold scope are you using?

2. How far apart were the two groups, center to center?

3. How many clicks on each of the adjuster knobs did it take to move the second group that far from the first?

Also, one last thing to consider......are you using the scope cranked all the way up to full magnification, and what power of magnification is that? (I'm thinking of parallax errors here....)

multiple68 wrote:

The Annoyed Man wrote:What are you shooting by way of ammo? Different loads will perform differently.

What bullet weights? This matters greatly, and is closely tied to the next question.

What barrel twist? If the twist rate isn't right for the bullet weight you're shooting, you're going to get bad results.

What caliber? (The SPS Tactical is available in .223 and .308) The Remington website says that the .223 version is a 1:9 twist and the .308 version is a 1:12 twist. For purposes of accuracy, in the .223 Remington, 1:9 limits you to 69 grain bullets and under, with 55-62 grain probably (but not necessarily) being optimum. In the .308 Winchester, 1:12 limits you to bullets in the 150-168 grain range. Here's the thing: The Remington website information isn't always accurate. MY 700, a 26" heavy barreled varmint rifle in .308 I bought back in 2007, was supposed to be 1:12 according to the website. However, the printed catalog said it was 1:10. That is a significant difference, and it will greatly affect accuracy dependent upon bullet weight. I contacted the factory and gave them the serial# of the gun and explained the information contradiction. They got back to me to say that 1:10 was correct; and shooting 175 grain Matchkings has born that out, doing significantly better than 168 grain Matchkings.

Until you can answer those questions, it would be difficult for anybody to give you any kind of valuable input. And after those variables have been sorted out, only then will addressing optics and shooter technique be worth any effort.

Please note: if yours is .223, DO NOT fire any ammo labelled "5.56 NATO" or "5.56x45mm" in it, as .223 Remington chamber/leade specs will not safely accommodate 5.56 ammo.

I will get this info later today, but it is a .308 and I think all rounds were 150

Would ammo cause not only that spread but also inconsistency? Some were high, some low. Some left some right

Yes, ammo can account for inconsistency, and that is basically the difference between match ammo and regular production ammo. Match ammo may not give you super tight groups, but those groups will be consistent; whereas the other stuff may give you one group size now, and a different group size later. But you'll never know the rifle's capabilities without trying some match ammo. So that begs the question, was it 150 grain match ammo, or was it just 150 grain inexpensive hunting ammo or FMJ? If you are shooting a .308 SPS with a 1:12 twist, I wouldn't waste too much time and money on cheap ammo....unless you were just plinking and not that concerned with accuracy. Me personally, in that rifle, I wouldn't shoot anything except A) Federal Gold Medal 168 Grain Match BTHP, B) Hornady 168 Grain A-MAX® Superperformance® Match™, or C) the approximate equivalents of these two loads from other manufacturers such as Lapua.

Also, get yourself a box of 165 grain Federal Fusion. This is very good hunting ammo and tends to be pretty accurate. I use it for hunting in my 700, which gives me groups varying from .5" to 1.5" at 100 yards, depending on how much coffee I drank that day. But at 165 grains, it is within the operating window for a 1:12 rifle, and group sizes in that range are more than adequate for reliable hunting accuracy.

Lastly, if you have the capability, try some handloads. I developed a handloaded 175 grain matchking which consistently exceeds Federal Gold Medal 175 grain match in my rifle. The Federal might give me .5" to .75" groups, and my handload gives me .375" groups.

What are you shooting by way of ammo? Different loads will perform differently.

What bullet weights? This matters greatly, and is closely tied to the next question.

What barrel twist? If the twist rate isn't right for the bullet weight you're shooting, you're going to get bad results.

What caliber? (The SPS Tactical is available in .223 and .308) The Remington website says that the .223 version is a 1:9 twist and the .308 version is a 1:12 twist. For purposes of accuracy, in the .223 Remington, 1:9 limits you to 69 grain bullets and under, with 55-62 grain probably (but not necessarily) being optimum. In the .308 Winchester, 1:12 limits you to bullets in the 150-168 grain range. Here's the thing: The Remington website information isn't always accurate. MY 700, a 26" heavy barreled varmint rifle in .308 I bought back in 2007, was supposed to be 1:12 according to the website. However, the printed catalog said it was 1:10. That is a significant difference, and it will greatly affect accuracy dependent upon bullet weight. I contacted the factory and gave them the serial# of the gun and explained the information contradiction. They got back to me to say that 1:10 was correct; and shooting 175 grain Matchkings has born that out, doing significantly better than 168 grain Matchkings.

Until you can answer those questions, it would be difficult for anybody to give you any kind of valuable input. And after those variables have been sorted out, only then will addressing optics and shooter technique be worth any effort.

Please note: if yours is .223, DO NOT fire any ammo labelled "5.56 NATO" or "5.56x45mm" in it, as .223 Remington chamber/leade specs will not safely accommodate 5.56 ammo.