I just purchased a new rifle to go deer hunting in lower Michigan. They allow straight wall cartridges so I picked up a Ruger American packaged with a Vortex scope, picatinny rail and rings from my local Dunham's. It is chambered in 350 Legend. (BTW season is over waiting for next year)

I cleaned it up, checked for proper torque on rings and base and took it to the range to confirm zero. Also since it is a new cartridge for me was curious about the ballistics.

Here's a pic of the target from first shot out of the box to adjusting zero and checking out 25 yd, 50 yd, 100 yd and 200 yd accuracy
I was shooting Winchester 180 gr Super X ammunition. I'm happy with the accuracy but not so much the printing to the right as yardages increase.

I can only think of three things that would cause this. Receiver holes drilled out of alignment, picatinny rail out of spec or rings off center

Sure would appreciate your thoughts on the problem and also what to do about it

Wind?

Are you getting about 2100fps with 180gr?

Rifle scopes don't "point" in a particular direction; you adjust the reticle to a point in space and it stays there on the same path to infinity. If they did, you would never be able to adjust the reticle to follow the shots. Even though the scope might not be parallel with the bore, that doesn't matter. As long as you see the reticle, that is enough. Whether you are looking precisely through the perfect center of the scope, or not.
Why your shots drift to the right, IDK.
I would adjust back to center (+2) and go hunting.

Not including the effect of any side breeze, you must remember that if you are off centreline at 25yds say 0.5", you will be 1" off at 50yds, 1.5" off at 100yds and so on.
Once a bullet is off centreline from leaving the muzzle to where you are aiming i.e. barrel is not pointing to your aiming point, the bullet keeps going in a the direction it starts at and a breeze will accentuate that either further off centreline or back towards centreline depending on the breeze direction.
For long range shooting you have to shoot in at a longer range to ensure the bullet is hitting the centreline similar to target below, first two shots cold barrel bridging centreline, third shot still only 0.25" off centreline and this at 100m.

The scope and barrel are pointing in different directions although the difference is probably very minute. Also, the scope may not be mounted dead straight and level, causing the rifle to cant slightly to one side when you mount the rifle for shooting and level up the crosshairs in your vision.
Pinpointing the causes is harder. It could be the very possibilities you mentioned, or a barrel cut off-centre, the barrel not sitting true in the receiver or, a crappy scope without a precisely centred reticle.
If you decide to solve the mystery without involving a gunsmith, and also if it were me, I would start by trying another scope, ensuring mounting is dead true and shooting the rifle before moving through the other checks trying to identify the cause.
The target indicates the rifle will shoot satisfactorily so I hope you get to the bottom of the issue. Good luck.

Is this your setup? https://ruger.com/products/ame...pecSheets/16934.html

If so, I'd can the rings and bases. We replace those all of the time with a Leupold rail and a good brand of vertical split rings. We find those rings and bases have a lot of slop in them. The other option is to use Leupold one-piece windage adjustable bases and rings.

But first, go back to the range and test for misalignment. Note the setting for your current windage adjustment. Screw the windage adjustment in, to its stop. Then back to the other stop. Count the revolutions and divide by two. Screw in that number of turns. This will center your erector tube assy. Now, send three at 100 yds. The group deviation off-center will indicate if your scope is pointed off-line from the bore. If it is, you have to figure out why.

The problem boils down generally to one of three things:

1. Off-centerline scope mount holes in receiver
2. Bases and rings sloppiness
3. Barrel not co-eccentric with receiver

The most likely culprit is #2. That's why I suggested earlier to replace the factory ones. I install 4-5 scopes every day six days a week, so I see a good bit of crappy mounts.

With modern machining methods it is highly unlikely the holes are drilled off-line or the barrel is not co-eccentric with receiver. But it is not unheard of. We have sent a few back for this.

Failing to find fault with the above, then IDK either. Send it back to Ruger and let them figure it out while it is still under warranty.

quote:

Originally posted by safarihunter:
I just purchased a new rifle to go deer hunting in lower Michigan. They allow straight wall cartridges so I picked up a Ruger American packaged with a Vortex scope, picatinny rail and rings from my local Dunham's. It is chambered in 350 Legend. (BTW season is over waiting for next year)

I cleaned it up, checked for proper torque on rings and base and took it to the range to confirm zero. Also since it is a new cartridge for me was curious about the ballistics.

Here's a pic of the target from first shot out of the box to adjusting zero and checking out 25 yd, 50 yd, 100 yd and 200 yd accuracy
I was shooting Winchester 180 gr Super X ammunition. I'm happy with the accuracy but not so much the printing to the right as yardages increase.

I can only think of three things that would cause this. Receiver holes drilled out of alignment, picatinny rail out of spec or rings off center

Sure would appreciate your thoughts on the problem and also what to do about it

Wind. Don't exactly have a great wind bucking cartridge there.

John

Scope is not parallel with barrel. Rings and mounts. Shim rings is easiest and cheap. Or Replace as suggested above.

I'm sorry but for those who say the scope is not on straight, don't know how scopes work. ONLY if the OP can't adjust the scope to make it come back to zero, is that the cause. (The OP did not say he could not bring the shots back to zero, all he said was AFTER shooting center at 25 yards, when he moved to 50 and 100, the shot group moved up and to the right.) I told him what to do; again, adjust the scope to zero, or two inches high at 100 yards, and go kill deer.
When you look through a scope, if you can see the reticle, it is pointing in the "right" direction. Even if the reticle is adjusted all the way to one side or the other, you can still see through the scope; the mechanical scope is not pointing parallel with the bore, but the optics inside, are.

quote:

Originally posted by Fury01:
Scope is not parallel with barrel. Rings and mounts. Shim rings is easiest and cheap. Or Replace as suggested above.

Could be. If the scope is canted a little and you naturally align the vertical wire with the trees, it's going to go off the centerline at a small angle.
My hunting partner likes his canted to make his wrist more comfortable, makes no difference in the field.
Small being the operative term here, at 200 yards it's not going to miss the deer's kill zone.

If ruger american has same recoil lug as 77 , I always use dial indicator to torque. I continue to tighten front until I can get 25inch pounds on rear with no movement. With bedding I have made tack drivers out of several rugers.

I agree with dpcd. Also, canting can cause considerable left/right errors with high trajectory shots.

Zero the rifle wherever you want it to hit at the max distance you will shoot. Make sure the scope is square on the rifle and be careful not to cant the gun when shooting.

Try a different scope, I suspect parallax.

1st try a different shooter, conscious of parallax and repeatable eye positioning, then next a different scope and mount.

at 100, set the POI to center of target

then shoot at 25, 50 again, and find the differences have been resolved

I'm with dpcd on this one as well as bunkum optics/mounts. In any case, it's within a minute of moose as it is.

5 mph wind is

1.3" at 100
5.8" at 200

I am quite familiar with how scopes work. Just pretend for a moment the op had asked about his side mounted scoped rifle, meaning one 1.5 inches left of the bore line instead and why he has windage errors at different ranges. Does that help understand my answer?
I have never had to shim a scope horizontally but have had to do one vertically to be able to use the internal adjustments in a reasonable fashion.

safarihunter -

We can rule out many thing including the scope adjustments "walking" because each distance has a nice consistent group.
The scope, mounts and stock bed seem to be fine.
Many factory barrels are straightened before they are mounted. It seems like this may have fallen short by a slight amount and even possibly bent left and further down bent right.

To test this theory.
Remove the bolt and take the barreled action out of the stock and lay it on it's side on a clean flat hard surface. Add a heavy weight to the side of the action to keep it firmly in place. Carefully shim the barrel end and also the center until there is no space under it.
Flip it over, add the same weight and see if the same spacers fit easily under the barrel. Keep a close eye on it as you shim. Don't force anything.

Keep us posted.

Safari; PLEASE come back and tell us if you can adjust the scope back to zero. If your adjustments are stuck to the right as far as they can go, then that explains it. (The reticle will have to travel right to bring the bullet left)
I am pretty sure your scope is not mounted 3 inches off center.

All you need to do is move the cross hair 2.4 inches left and you will be sighted in a few inches high based on your two shot 100 yard group. The rest is hogwash..I think thats what DPCD is saying and he "coulden be righter".

I appreciate the comments that I have received

I agree I could zero the rifle at 100 yards and it would shoot minute of deer with a little Kentucky windage on longer shots

Since this is a new rifle I called the factory to see what their thoughts are. The following is the email I sent to them. I am looking forward to their response

Thank you for your assistance this afternoon regarding the new Ruger American rifle that my son in law recently purchased.

I will try to document our conversation and the details as best I can. I will also include a picture of the target I shot at 25, 50, 100 and 200 yards in an effort to visually show what I am describing.

Ruger American 350 Legend s/n 690545992


As a first time hunter with his first rifle, my son in law asked that I assist him in sighting in his new rifle.

Prior to leaving my workshop for the range, I made sure the rings, base and receiver/stock were torqued to recommended settings. I also made sure the reticle was parallel to the axis of the bore using the Wheeler bubble leveling tools.

The weather conditions that day are as follows. 12/2/2021, 56 deg F, wind out of the west 5 mph, (the range is oriented from east to west - I was shooting into the wind). The ammunition was factory Winchester Super X 180 gr sp.

My target was initially placed at a measured 25 yards and a shot was fired to determine where the ammunition was printing. From there I walked the shots to a zero at 25 yards. (Shots 1 thru 7)

At this point I walked the target frame to a measured 50 yards and fired two more rounds. The rounds printed 1 5/8" higher and 1/2" right of the 25 yard zero.

I then walked the target frame to a measured 100 yards and fired two more rounds. These rounds printed 1 1/8" higher and 1 7/8" to the right of the 50 yard group.

I then walked the target frame to a measured 200 yards and fired three more rounds. These rounds printed 8 1/2 " lower and 3 7/8" to the right of the 100 yard group.

The rise and drop of the fired rounds are not an issue. Simple gravity. I am concerned about the rounds printing 6 1/2" to the right of the 25 yard zero.

Based on the printed groups, the ammunition is accurate and the rifle shoots accurately. Sub MOA at 200 yards is pretty good in anybody's estimation.

Something is causing the rifle to shoot right. Need to resolve this issue. Kentucky windage is not an acceptable solution

Regards,

I do hate to point this out, and I am sure I will get hate mail for it, but your rifle is performing normally. And it also shows why we, or most of us anyway, don't zero big game rifles at 25 yards. What if you had zeroed at 50 yards? Then, everything would be normal and would hit POA, at 100 and 200. Because, as your target also shows, the shot path is linear and is reacting exactly as you would expect; as each range doubled, so is the bullet deflection. And if you did zero at 50 or 100, then go back to 25, I submit it would still be on target.
So many variables are multiplied at 25 yards, that I just don't trust a zero at that range.
How many AR members do?
Think about it.

Do you change your shooting position? Going from sitting in a bench to prone can make what change of impact.

Cant the scope a little clockwise and line up the vertical wire with the trees in the background. It will be all good...

Hot barrel?

A zero at 25 yards has little practical use. It's only practical use is to get you on the paper at 100.

Your rifle actually appears just fine to me.

It's 1 inch right @ 50, 2 inches right at 100, and 4 inches right @ 200.

Re-zero rifle at 100 and I bet you will find you are just fine at 50 and at 200.

Nobody mentioned spin drift?

I do recommend this way of setting scope plumb: shooting it!

I will get the scope on paper at 10, 15, 25 yards, depending on range condition. I sort of bore sight at home, take the rifle to the range, and put a political campaign sign up close, and see where the bullet hits! Sometimes at 10 yards the scope is not on poster.

Then I move the target out to 100 yards and get the group in the black, in the middle. And then I move to the plumb bob target.



A plumb bob was lined up in the center of the bottom target at 100 yards. I went up 30 plus MOA to determine if the scope was plumb to the bore. Pretty much it is. The group went up in a straight line (more or less) with the plumb bob string. If the scope was off axis the upper groups would be offset diagonally left or right. And, this is where I found that this scope is not exactly 1/2 MOA clicks, and is definitely not 1/4 MOA clicks.

If the upper groups are offset diagonally, rotate the scope in the rings. I forget the direction, clockwise moves it one way, counter clockwise the other.

I counted my clicks up to "0"



And at distance, it is close enough given the wind conditions and my body placement on the rifle.

These old 174 FMJ's shot well out to 300 yards.







The 168's were always a more consistent bullet than the old military match 174's.





175 SMK printed close, this is not a gimme for most cartridges. Changes in bullet weight and profile result in big point of impact changes.



at distance, wind has one heck of an influence where the bullet lands, and unfortunately, I don't have a 600 yard wind tunnel.



Three shot groups don't prove anything. Why humanity accepts three shot groups is an interesting example of human biases. I think it is due to symmetry. Would you accept a one shot, two shot group, or a four shot group as an example of accuracy or consistency? Probably not. None of these group counts mean anything statistically about consistency, lines, squares are not pleasing shapes, but humans like three shot groups. Three points make a triangle, humans seem to like triangle shapes, triangles are easy to visualize. Humans don't like asymmetry, would people accept a pentagon as a shape that defines accuracy?, I think not. A pentagon does not provide a pleasing middle center.

Gunwriters like three shot groups because they are paid a flat rate, they don't want to shoot a lot of ammunition because it costs money and time. They have found through trial and error, the shooting community will accept three shot groups as a measure of accuracy. Three shots means nothing.

No one mentioned spin drift because at those ranges, bullets don't drift that much from spin. His bullets are following the path set upon them by the last 3 calibers length (diameters) of the barrel. IE, for a 350, the last 1 inch determines where the bullet will go.

quote:

Originally posted by Dan Stone:
Nobody mentioned spin drift?

It is so obvious. A slow, round nose bullet loses velocity quickly, and drops quite a bit over the course of 200 yards. This is a recipe for the spin drift (which will be to the right with a right-handed rifled barrel) to show up fairly clearly. The faster the bullet drops compared to its forward motion means that the air pressure under the bullet is relatively greater than that above it, therefore it acts like a tiny propeller or wheel turning against the denser air underneath it. The target is a perfect example of a slow bullet drifting (due to spin).

Over the years I've found that high velocity rounds are best when sighted about a quarter inch left at 100 yards. They tend to move back to the right and overcome the leftward angle by the time they reach about 300 yards. Just ask some of the benchrest guys.