Need help...scope issue (maybe)

[TheLion]

Hi All,

I have a S&W M&P 15 Sport and picked up a Nikon m223 scope that I mounted with a LaRue mount so I can switch to iron sights to mix it up, and have it more or less zeroed in at 100 yards. The rifle eats any ammo I feed it, I was shooting cheap MFS ammo but decided to be a little more kind to my rifle and am now shooting PMC Xtac (62 grain). It's a little cleaner, albeit the accuracy for my novice abilities at this point is relatively the same. I have noticed when I am shooting at a paper target I can get maybe 1.5 inch groupings when I aim at the center of the target. For my level I am more than pleased with this and know I'll tighten it up as time goes on. Now here's my quandary, when I have the little high contrast stickers placed around the overall target I get varying results. When I shoot above the center of the target my groups tighten. I like that! When I shoot at stickers that are below the centerline of the target they get worse, to the point where I'm shooting 3-4inch groupings. It gets even worse if I shoot below center right, in this case I get 6 inch groupings. I casually asked a guy with the same basic setup as me and he says you have to adjust when aiming at different parts of the paper. In my mind I have a hard time fathoming why that would be the case. Any input from you experts would be appreciated.

I am always aiming at the center bullseye of each high contrast sticker.

I am shooting at 8X magnification during these issues.

I'm shooting bench rest off a wooden stand with the bags resting on top so the rifle isn't resting directly on the wood.

I place the upper targets maybe 8-12 inches above the equator of the target, and the same below for the lower group of stickers. Then I space them apart by about 6 to 8 inches on the new midline. Is it possibly a parallax issue? So my overall target would look something like this:

....................
...X.....X.....X....
....................
...X.....X.....X....
....................
...X.....X.....X....
....................

Thanks!

 

[hlee]

Re: Need help...scope issue (maybe)

Adjust your natural point of aim for each target. Small variances in how you are holding the gun can produce large variances in shot placement down range.

 

[TheLion]

Re: Need help...scope issue (maybe)

I'm guessing that is likely what it is as I have been very consistent with my odd groupings. Practice practice practice.

 

[problemchild]

Re: Need help...scope issue (maybe)

Could be position of hold and could be paralex. Sit the rifle on sand bags so it cannot move and then without touching the gun at all move your head slightly up and down and side to side. If the crosshairs move on the target you have a problem.

 

[TheLion]

Re: Need help...scope issue (maybe)

Thanks, I'll be trying that next trip out to the range. If so I'm taking the scope back.

 

[hlee]

Re: Need help...scope issue (maybe)

You do not say what model scope you are running. Is it a model with parallax adjustment? If not, you should be aware that all scope have parallax "issues." The important part of what problem child wrote is that "you have a problem," not necessarily that your scope has a problem. Parallax is simply an artifact of having two objects at different distances focusing on a single plane. (As an exercise, sit in the passenger seat of a car and read the speedometer. Your reading will be lower than the driver's due to parallax.) Most scopes for center fire cartridges have the parallax set at around 150 yards. I find it hard to believe that your bullet placement is off by 6" at 100 yards due to parallax. Even still, properly positioning yourself behind the scope- and doing it the same way every time- eliminates parallax problems.

It is more likely that you are muscling your gun into position, rather than getting it to its natural point of aim. The result is that your trigger pull is not consistent, and the gun rebounds off of you and the rest inconsistently- throwing off your shot.

It is also possible that not properly aligning your head to the optic (caused by not properly adjusting the gun, and causing parallax problems) is contributing to your inconsistency.

Either way, practice and not a new scope is your best solution.

Edit... The 2-8x32 Nikon M-223 is adjusted to be parallax free at 100 yards.

 

[TheLion]

Re: Need help...scope issue (maybe)

Thanks for the tips guys. I have no doubt I am a part of the problem, I have many many rounds to go before I'm half way decent. I just find it odd that I produce these results very consistently. It likely has to do with how I'm handling the rifle at slightly different angles. Including me potentially compounding any parallax issues (if any at all) by my own inconsistency.