When adjusting for a couple of inches, the next shot is a foot off. It seems to wander all over the target.

You need a target with grids set it at desired distants take three shots at the top or bottom of your breath don\'t pull the trigger squize it the shot should almost be a suprize to you and make sure you are in a pron or steeded position then retive target draw a line to each hole find the middle count how many bloks to center up and over or down and over then open the adjusting caps most scopes are 1-2 clicks for every 1/4 inch then take three more at the same distance position with the same breathing and repeat after that the next three should be right in the middle hope that helps

Your scope should be "in the ball-park" out of the box. This ball park will of course be determined by the height of scope rings you put on your rifle. The taller the scope rings/bases the lower your initial shot... Go to a range or safe outdoor shooting area. Put a large target up at 100 yards, 16"x6" will usually do. Aim at the bulls eye, and click off a round. Use a spotting scope, binoc's or your scope to see where your shot has hit. If it is off the paper and no where to be seen, click off a shot one foot high, check paper, repeat one foot low, one left, one right until you find your shot on paper. Once you find your shot, you will need to adjust the windage (left to right) or elevation (up to down) by using the turrets on the scope. Part of the trick in sighting in your scope is to remember if your shot is high, then you need to crank the turrets in the "up" postion (if it shoots left, turn turrets to the left, and so on). This part is sort of counterintuitive, and may feel foreign. Once you get your scope on paper, continue to adjust until you are hitting consistently 1 inch above bulls at 100 yards. Shooters benches and rifle rests help in this process, but it can also be achieved without. I hope this helps. D

Start out at 25 yards. the scope is I believe used 1/4 inch clicks. This is for 100 yards so 16 clicks will equal 1 inch at 25 yards. Fire three shoots from a solid rest. Measure the distance left or right and up or down from the desired point of impact. and move the setting in the desired direction. ie uo is moving the point of impact up from where it is. and left or right is the same. Next fire at the desired distance and move point of impact to where you want it at that distance. If the scope is wandering all over the target make sure the scope is not moving in the mounts. If it persist in changing point of impact send it back to tasco for a replacement as it has a loose recticle. Better yet I can recomend Leupold or Burris as a better alternative if they are in your budget. Not quite a S&B or Ziess but **** close for a lot less $$$$$

You move the cross hairs to the shot. Set up your gun on a bench and start by firing at a target out at about 15 yards. Once you are "on paper" set your cross hairs on the center and fire a 3 shot group Adjust the scope to the group. if the group is down 3 inch and left 4 inch. Adjust your scope accordingly. Then Fire another 3 shot group, until you are shooting center. Every time you adjust your scope tap the barrel of the scope with a screwdriver handle to keep the cross hairs from sticking. Once on at 15 yards move out to your max range and adjust to that.

The Bushnell 3-9X40 has been around for quite some time in several forms, but it is pretty standard to set it like any other scope.

With the gun resting solidly on sand bags or something like a Lead Sled, shoot at a target with a 1" grid on it. Those targets are a free download at http://targetz.com/, but you have to browse to find them. Targets No: 10049 or 10058 are both usable, if you can see a 1" aiming point with a 9 power scope at 200 yards.

With a known point of impact (POI) at 200 yards, you can move the POI to where you want it (inside the caps at the center of the scope, there are adjusting screws or slots). The norm is 1/4" per click (the adjuster can usually be felt to click) at 100 yards or four 1/4" clicks for an inch. At 200 yards, the adjustment will be twice what it is at 100 yards or 1/2" per click.

Make your adjustments, using the grid on the target to tell you how many inches it needs to move, and shoot the target again to confirm the adjustment is correct. It's pretty standard to shoot at least a three shot group to ensure the bullets are reasonably close to each other.

Another method is to set the POI at a certain number of inches high at 100 yards and assume it's right at 200 yards. If the mid range trajectory, for your cartridge, at 200 yards is X inches high at 100 yards, you can set your POI to that X inches high and be pretty close at 200 yards.

First is to try for a group, do not adjust the scope in any way. Shoot 4 rounds with out adjusting the scope. The gun should settle down and start to group. If you can not get a group in 6 rounds go clean that gun & check your ammo. Start over. If she does not group, its the gun not the scope. Once it starts to group move the cross hairs in the opp direction small clicks and "TAP' the scope after each adjustment. Shoot for a group each time 2 rounds should group. Get a target that has a grid to help get on faster. 

I doubt if there is anything wrong with your scope.
The Baraska model A10810 Reticle adjustments are 1/8 ( 1/8 inch) MOA (minute of angle).
For instance, Look at the top turret (The ELEVATION Adjustment Knob). You will see that there are little vertical 'hashmarks' all the way around the knob starting with a '0' then a series of the verticle hashmarks, then a '1' and another series of the marks, then a '2' and so on. YOUR scope will have 8 of those vertical 'hashmarks' between each 'number'. These little 'hashmarks are referred to as 'Clicks' or 'Minute of Angle' adjustments.
Now imagine that you are set up on the 100 yard line and you have fired a round at your target, say a one inch diameter dot or any size for that matter, and the bullet strike was one (1) inch LOW and two (2) inches to the RIGHT and of course you now want your next round to impact in the target dot.
To bring your bullets point of impact UP to coincide with your point of aim (you have your 'crosshairs or RETICLES centered on the dot), you will be turning the TOP adjustment knob CLOCKWISE, ONE 'click' at a time. EACH one of those 'Clicks' will actually move the horizontal Reticle UP (Elevation) or DOWN 1/8 of an inch at a time. If the bullets point of impact was 1 inch LOW, you would need to turn the adjustment knob clockwise Eight (8) clicks which will equal ONE (1) inch.
Now you must adjust the knob on the RIGHT side of the scope. This one is the WINDAGE Adjustment knob which controls the VERTICAL Reticle and moves the point of impact Right or Left. This knob will also have the 'hashmark' increments around its perimeter and like the Elevation knob each 'Click' will move the Reticle 1/8 of an inch but in this case the Reticle and point of impact moves Right or Left.
Remember the bullets point of impact was 2 inches to the RIGHT. This means you must adjust the Reticle or point of impact to the LEFT so that your point of impact will coincide with your point of aim and will be in the target dot. Turn the adjustment knob COUNTER CLOCKWISE Sixteen (16) Clicks. Keeping your POINT of AIM (crosshairs centered on the dot), your next round should be inside the dot and you can then fine tune it from there.
As you can see from this example, the Reticle (crosshairs)and point of impact does not travel very far at all inside your scope at the 100 yard distance so it is not hard to imagine that you thought they were not adjusting to get you on target, when in fact they WERE adjusting, but in tiny increments.
Now, as you create more distance between you and your target, these 'tiny' increments and point of impact will be larger as your distance increases. For example, at 200 YARDS each 'click' will move your Point Of Impact 1/4 of an inch right,left,up, or down. So if your bullet point of impact was one (1) inch low from the 200 yd line you would adjust your Elevation Reticle 4 Clicks to raise your point of impact in order to be on target. At the 300 yd line each Click will adjust the point of impact up,down,right or left, ONE (1) inch.
If you wish, I would be happy to walk you through the 'ZEROing In' of your scope and rifle even if you do not have a Zero Bore Scope. With-in about 9 rounds you can be hitting where you are aiming instead of 'chasing' bullet holes all over the paper.
If you are interested, respond back and I will be glad to assist you. Enjoy. :)

Real simple Scott.
You can 'Zero' your scope/rifle even if you don't have a laser bore-scope device.
All this is assuming that your used rifle has not had the barrel shot out and that the head-space is still within specs for that rifle. Have all this checked by a gunsmith first. You can dress up a piece of poop and it will be pretty, but still be poop. Make sure yours isn't to begin with. As for the scope, it's hard to tell unless there's obvious damage or it's an antique past it's prime. Try to get as good a quality scope as possible to start with. You would not put one ply tube tires on your mustang and expect to get the best performance, so...
Most rifles are capable of shooting quite accurately, and all things being equal, it's the shooters job of making it happen.
Ammunition should be considered as well. Toss your old military ball ammo and junk from overseas, both of'em. If you want to shoot accurately and consistently, you must spend the bucks for the best ammo you can afford.
You MUST KNOW what the BALLISTICS are for the Cal./type/weight ammo you will be shooting and the corresponding distance it will be shot from.

Make sure your rifle is CLEAN inside and out. A clean rifle is a happy rifle.
Make sure that your rifle 'fits' your body's frame and that you are familiar and practice good rifle shooting techniques.
'Zeroing' is best done from the prone position as that is the most steady position to shoot from.
Do you have a bi-pod attached? Whether you do or not, sandbag your rifle securely but still able to make small adjustments to the rifle position itself.
Set up a target with a 1" black dot at 50rds.
Remove the bolt.
Lay down with your rifle but stay OFF of it, touch it as little as possible at this point.
With out disturbing the rifle look through the bore downrange to your target. Locate the black dot and if necessary adjust your rifle from the **** end until you can see the dot through the bore. Keep making minor adjustments until the dot appears to be centered in the bore. Make sure rifle is secure and steady at this point.
Then without moving or touching the rifle, look through the scope using the correct eye relief distance and locate the black dot. Now using the Vertical(Elevation) and Horizontal(Windage) adjustment knobs, move the reticles(crosshairs) until they both are centered on the dot.
Again look through the bore to make sure that you have not moved the rifle and that the dot is still centered in the bore. If not, adjust the rifle again to center the dot, then go back to the scope and adjust as necessary to move the RETICLES to the center of the dot. It may be necessary to repeat this a few times before you have achieved this particular goal.
You do not mention brand/model of your scope. It probably adjusts the reticle or crosshairs in 1/4minute increments (1/4 inch increments with each individual click movement of the turret knobs at 100 yard distance). IT IS CRITICAL for you to know how your own scope adjusts.
Now, bolt back in and load 3 rounds of quality ammo.
You are going to shoot 3 rounds in succession without getting off the rifle or making any adjustments to the rifle or scope. You are looking for a 3 shot group to determine a rough average of how far and where the rounds are impacting initially. Use good shooting techniques, breath control, relax, sight picture, squeeeeeeze the trigger, follow through the scope, there is no need to take your eye off the scope while doing this, hold your shooting position for all 3 shots.
You will now have to make adjustments of the scope unless you are hitting the black dot already which is quite possible.
Remember that if your scope is a 1/4" adjustment at 100yds, it means that for each 'click' that you adjust either Vertically or Horizontally at 100rds, the reticle/crosshairs will move accordingly 1/4 of an inch Vertically or Horizontally. At 200yds, one click will move it 1/2 inch, at 300yrd it will move it 3/4 of an inch, at 400yrd, it will be 1 inch.
Right now you are at 50yrds distance from your target. Each click from here will move the RETICLES about 1/8 of an inch so estimate the distance that your most central shot of the 3 you fired, is from the black dot and adjust accordingly. You're not moving the RIFLE here, you are simply moving the scope RETICLES so that your point of aim and point of impact coincides.
Now load 3 more rounds of ammo and repeat as above. You should only have to use about 9 rounds to get on target, the black dot.
Once you are hitting the black dot at the 50yrd line, move back to the 100yrd line. Put a fresh black dot on your target and repeat the steps from above. Your first 3 shots from the 100yrd line should be about 1/2 to 1 inch low. Don't follow the bullet strikes! Keep your point of aim and the crosshairs ON the black dot no matter where the bullets are striking on the target. Remember, now at 100yrds your RETICLES will move 1/4inch with each 'click' of adjustment of the turret knobs.
Adjust the scope as needed at this point. Once you are 'ON TARGET'(hitting the black dot), you now have your 100yrd. 'ZERO'.
Now that you have this 100yrd ZERO, you must loosen the turret knobs , both the Vertical(Elevation) and the Horizontal(Windage) turrets and align the '0' on the knobs with the '0' on the scope at the base of each knob. Now tighten the set screws and you are set to go. If you want to know your 200yrd 'ZERO', simply move back to the 200yrd line, your 'come-up' or elevation adjustment should be about 7-9 clicks, at least for .308 168grn HPBT, but you will figure it out for the Cal./brand/wght ammo you are using. WHATEVER the 'come-up' you need to make at 200, 300,400yrds or wherever, be sure to make note of the number of clicks you used to find the Zero for that distance. Use a fine point endelible marker and actually write the ZERO info on thestock of your rifle. You don't need to mark anything for the 100yrd ZERO, it's a given already. Write; 200/9, 300/18 and so on. You should also get your ZERO for the intermidiate, 150yrd, 250yrds etc, distances as well.
Remember that weather conditions, source and intesity of light conditions, your own body condition at any particular moment or day can have an affecf on how you and/or your rifle shoot. Good luck.

Keep in mind Diane this is for a set distance. if you are taking a shot at a target further than your are set for (ie a target you wont get 3 shots @) remember how the bullet is travelling as it goes down range

one idea would be to set your rifle up down range and zero it in on a target (preferably paper) now adjust 1 MOA (try and have target @ 100 yards and 200 yards)

see how far the bullet moves for each moa adjustment. then check it against the next range.

this should remain constant @ a set number of inches per 100 yards.

so if you zero in @ 100 yards and then move 1 moa any direction and it adjusts (lets say and hope it is 1.047 inches") then you do the same for 200 yards. it should be twice as much movement. ie 2.094"

once you know what 1 moa represents on your scope you can adjust alot more accurately.

REMEBER the total inches of movement / adjustment per MOA is directly related to range (a precise range helps in shooting) so if your squirrel is 150 yards and your first shot is off 9" to adjust you divide 9" by the inches per moa so 1.5 (150 yards /100) X (Inches per 100 yards per moa you measured hopefully 1.047") its 9" divided by 2x1.047 = 9" / 2.094 = 4.29799

this number needs to be rounded to the nearest click on your scope (most are 1/4 MOA scopes and you can tell by looking at how many clicks/lines are inbewteen each large number on your windage and elevation dials

so to turn this into an adjustment we round 4.29799 to 4.25 which is 4.25 MOA or 17 clicks on a 1/4 min scope.

GL and any questions just post and ill help

not please rate this as fixya :)

Note i can provide EXACT information that would allow you to determine range, and windage and elevation adjustments by looking through scope and estimating range
then factoring in weather variables. NOTE you hafta enjoy math or just want to know how to shoot really well. :)

Ja, it's 1/4 M.O.A, so at 25 yards/meter it'll be ca 3 inches. You may have gone in the wrong direction. That is, if it was 3' high, and you went another 3 higher then you'd be at the top of the paper. Probably you've got it figured out by now.

The easiest, fastest, cheapest way to zero is with a rifle rest you can clamp your scope into, or alternatively somehow immobilize your rifle some other way. You take a shot, at 25 yards or so. It makes a hole. You now immobilize the rifle, via your rest or heavy sandbags, with the scope pointing exactly where you aimed before. You now, carefully and without moving the rifle/scope off of the point of aim, dial your reticle to point at the actual bullet hole. Your next shot will be at your point of aim now. So you just put it at the right height above your point of aim at 100 yards now.