Anschutz rifle tracking on rest and bag

[Snozzberries]

I've been shooting my Anschutz 1813 off a front rest and rear bag. I've noticed that when sliding the rifle rearward and forward, that it doesn't track properly. Instead of the reticle simply going up and down, it's moving at an angle.

I've confirmed the bench is level, the reticle is horizontal, the rest appears level. I have a front for-end adapter on the stock to give it great stability. Any ideas?

Here is a quick video showing it.

And a photo of the setup.

 

[Leeman]

If you're sure your front and rear bags are aligned then it may be cast in the butt stock which is causing this. Being designed for prone shooting it is likely and looking down on the cheek-piece in your photo it certainly looks to me as though there is cast in that stock.

 

[Dusty Stevens]

You can get a gunsmith or stockmaker to make you a rudder for the back of that stock parallel to the front and barrel. Also get a rudder plate milled into the front of the stock. Bag riders make it ride too high and arent as solid as they need to be if they come on and off, then youll probably have to work on the fill in that rear bag. The easiest and cheapest route would be to get a proper stock. To make that one track like you want is just not feasable

 

[foxguy]

If you're sure your front and rear bags are aligned then it may be cast in the butt stock which is causing this. Being designed for prone shooting it is likely and looking down on the cheek-piece in your photo it certainly looks to me as though there is cast in that stock.

I have two Anschutz's, a 1968 1413 and a 1966 1411. Both have cast off built into the stocks. I too suspect the cast off is causing the tracking to move that way.

 

[Hi-NV Shooter]

If you're sure your front and rear bags are aligned then it may be cast in the butt stock which is causing this. Being designed for prone shooting it is likely and looking down on the cheek-piece in your photo it certainly looks to me as though there is cast in that stock.

That is correct, the factory stock has cast off example of what the difference is from center of action