I reload for a Blaser B95 combo 12-70/30.06 with a free floating rifle barrel.

Currently I reload 180 gr. Hornady spire points over 56,5 gr. N160, CCI 200 primers and Norma brass. Bullets seated out to slightly touch the lands. Kahles scope on a Blaser saddle mount.

Yesterday I was at the indoor 100 mtr, range again to test rifle and load.

Bullets 1, 2 and 3: almost touching, slightly to the left and slightly low of desired p.o.i.

Gave the scope two clicks to the right and three up.

Bullets 4, 5 and 6: Dead on where I wanted them, nice clover leaf, almost touching.

Bullet 7: 5,5 inches above 4,5,6, no horizontal deviation.

Bullet 8: 4,0 inches above 4,5,6, no horizontal deviation.

Bullet 9: touched bullet 7, no horizontal deviation.

Buller 10: 1,0 inch under 4,5,6. no horizontal deviation.

I looked at everything I can think of:
* powdercharges weighed and double checked.
* barrel crown is ok.
* no more than 30 bullets through since last
bore cleaning with Wipe-out
* scope was sent to Kahles and found in order.
* saddle mount adjusted to Blaser
specifications.
* barrel is free floating.
* 5 minutes between each shot to allow barrel
to cool down.

I shoot over a bench rest under the fore end and a sand bag under the stock, trying to keep the rifle in the same position and add the same pressure from shot to shot.

Does this vertical stringing indicate a known, typical problem with scope, rifle, my reloads or anything else?

The short answer is yes, but I have no idea if this could be the culprit with your particular set up as other things not scope related can also cause this problem.

It is far more common than most people think to have a reticle slightly shift its position inside the scope from recoil. This can cause a slight parallax shift that can result in vertical stringing of shots.

When we shoulder a rifle the stock normally dictates where our head and eye are placed horizontally behind the scope, but NOT vertically.

Perhaps the easiest way to start a process of elimination is to put another scope on the rifle using the same rings and bases and see if the problem still appears. If it does, then there’s a good chance that it is being caused by something else. Then swap rings and test it, etc, etc.

You can do all this stuff yourself, but it is beyond most of our abilities to pull the scope apart to check to see if the reticle mounting is loose inside the scope. That pretty much needs to be done by the manufacturer or someone specializing in scope repair.

Good luck.

This is a quiet interesting problem, that happened to me too.
FYJ's answer was really good, but sometimes not easy to be hold in.
The vertical postion of the shooter's eye should be the same at every shot as well as the uncorrected form of the sand bag because of the differences in the density of the stock-supporting part of the sand.(Also a VERTICAL problem)
Hope, it will help you!

I would suggest two things to look at: First of all, if you have a chronograph, are you using it and watching velocity during the string? It would have to be huge swing to cause the stringing you are seeing @ 100 meters, but stranger things have happened.

Second, it could be an issue with your sizing procedure. I would see if the stringing persists with factory loads.

If neither of those two approaches bear fruit, then I would believe the scope and or mounts are the issue.

reindeer,

Weird, but strange nevertheless. Good advice above, too.

To eliminate the optics issues from the rifle - shoot a group with the open sights at 25/50 meters using your ammo/bag/rest combination. That ought to determine if the rifle/load is suspect or on track without the optic/mount.

If that's O.K. start again with the scope mounted, first check Saddle Mounts screws and/or ring/rail screws. If you have the correct sized screwdriver the Saddle Mounts can be adjusted to ensure correct fit. Turn Saddle Mount upside down and ensure the ring/rail screws (Torx) are tight.

Apparently Kahles has confirmed the scope is O.K.? I had similar on a Kahles years ago after an around the world flight with my rifle. It started shooting two distinct groups about 10" apart - net, the crosshair (recticle) had given up the ghost and needed replaceed.

Could very well have been that adjustment "clicks" didn't set correctly in the tube. When making fine adjsutments like you mentioned (1-3 clicks) I normally double the amount of clicks and return the opposiste direction ensuring the every "click" is just that - an audible click and the adjsutment screws have no play in them.