bullet flight question

phutch30

Beginner
Jun 19, 2007
57
1
I am having a bit of a problem with my rifle. First off its a 7mm with a 26" barrel shooting 160 gr partitions at 3030. The scope is a leupold VXIII 4.5-14x40, with a custom BDC made for this rifle bullet combo.

100 yard group is 5/8" group dead on
200yards its a 1 1/2" group but 2 1/2 to the right
300yards 2" group 2 1/2" to the right
400 3 1/2" group 5" right
500 5" group 8"-10" right

Any ideas why I am getting the right drift after 100 yards? these are all 3 shot groups with a cool barrel off a bench in calm or at least low wind (5mph or so). When there is a wind its not a wind to the right.
 
Several things come to mind: mirage, parallex, location of the sun to your shooting position. From your group size, I don't think it is the shooter. I would give it a couple clicks left and try again.Rick.
 
If you are using the reticle hashmarks below the normal zeroing crosshairs is it possible that the scope is not quite mounted level on the gun??
Sounds like you have a great shooting gun that's performing under moa. If the scope is perfectly mounted and the gun is level in your shooting cradle I guess I would zero it using the 300 yd mark (at 300 yds) and then see where it is with the other zero's...if it's off a tad to the left at closer yardage it probably wouldn't make a bit of difference for normal hunting.
 
This scope doesnt have the yardage marks it has a custom made bullet drop compensator that replaced the elevation adjustment knob. Its a dial and shoot process.

I am pretty sure its not the sun or mirage. I could be the parallex. too bad my scope doesnt have a parallex adjustment.

I realize its moa, however I am anal about stuff like this and want to cure the drift if I can.

Thanks for the responses so far
 
Due to the way scope adjustments work, at times a vertical or horizontal adjustment will effect the other component. Call Leupold and ask them about your scope.Rick.
 
rick smith":ywdw19wk said:
Due to the way scope adjustments work, at times a vertical or horizontal adjustment will effect the other component. Call Leupold and ask them about your scope.Rick.

+1

JD338
 
If the scope reticle isn't perfectly vertical, dialing up elevation can also induce a windage change.

Sometimes it's tougher than a fellow would think to keep a scope straight, that's why some of the precision shooters use a small bubble/level on their scopes.

One way to check this is to shoot it on a large sheet of paper at 100 yards, and dial in your elevation for 200, 300, 400 & 500 yards, shooting at each setting.

The shots should impact in a straight line up from your 100 yard shot... Often a shooter will find that they are moving off to the right or left as additional elevation is dialed in.

Hope it's something this simple! :grin: Regards, Guy
 
My first thought was spindrift error but that's way too much. It has to be your scope reticle not being vertical. Dialing will exposed the error even more when shooting at longer ranges.
 
Well I dont think its the reticle. I just did a full revolution on the elevation dial and all 3 shots were in a 1/2 group 14.7" high dead center on the centerline on the target. Then dialed it back to 300 and 3" off. This in driving me nuts. It makes no sense. It has to be me. I must be pulling it. But my groups are tight all the way out to 500.
 
Dito to all the coments and as once stated sight in at either 200 or 300 yards using the corrisponding mark and then see how it groups at 100/200/300/400/500 yards. The horizonal line on your scope mite not be level to your gun.

At this point you know more about your rifle/scope settup than 95% of the hunters who feel their capable of 500 yards shoots but have never even shot at a 200 or 300 yard target.

And which direction was the wind blowing 8 inches at 500 yards may have been out standing for that days weather conditions. I would rather shoot with a cross wind than a wind head on. The bullets speed and trajectory is not linner so the effects of cross winds arn't as well. I am not a long range compation shooter but there is still alot of consistancy in your data I bet you will figure it out.
 
Back
Top