possible causes of horizontal stringing

[Willoughby]

I bought my then young sons identical R700 SS Mtn rifles in 3006 with pencil barrels and Leopould vxiii scopes in 1988? ish
they both shot well for all these years , and one still does print 3 shot moa groups -good enough for hunting , the other one recently started horizontal stinging, first cold shot may hit a inch or so from center , next 2 shots will be 2 inches left and 4 inches left of 1st shot , but perfect horizontal line , Ive checked scope mounts, and bedding all seems to be in order, I bedded both rifles some years ago with devcon and steel pillars - Im out of ideas . Im thinking swapping scopes , but Ive never had a Leopould fail, any ideas appreciated , thanks in advance

 

[JEFFPPC]

Very easy, switch the scopes gun to gun after checking bases are still tight. I have often found bases loose when checking similar problems for people. And any brand scope can and do fail.

 

[SSL]

Is this from a clean barrel each time? If so, what happens with subsequent shots as the barrel fouls? If the group settles down, obviously the barrel requires a certain amount of fouling to group. I had a Weatherby .257 Magnum that did exactly that. It had to have at least 5 shots fired before it would group...and it too had one of those buggy whip barrels.

On the other hand, I also had the same thing happen on a different rifle and it turned out to be a weak tensioning spring (for want of a more technical description) on the horizontal adjustment. Each shot jarred it just enough to move the crosshair an additional 3 clicks right (group left). Scope had previously been flawless. As to scopes failing; it isn't a matter of if, it's a matter of when. Some just take longer to fail.

Good luck and keep us posted as to what you find.

 

[RWO]

It's LEUPOLD! dammit. NOT "Leopould"

 

[garandman]

It's LEUPOLD! dammit. NOT "Leopould"

I've given up on the butchery being done to Lou O. Pold's name.

 

[JEFFPPC]

I've given up on the butchery being done to Lou O. Pold's name.

Dont forget Knight Force scopes, lol.

 

[garandman]

Dont forget Knight Force scopes, lol.

Your recommendation to simply switch scopes (put the good scope on the offending rifle) and check the rings and bases was a tiny bit of genius.

My experiences with pencil barrels have never been good. They heat up fast and walk long distances.... for me, anyway.

 

[carlsbad]

Moving as it heats up could be differential heating, especially on a light barrel. I'd make sure I have good clearance around the barrel, and that the bedding is still seated well, and the action screws are tight. --Jerry

 

[carlsbad]

Yes, a bent barrel can move as it heats up.

 

[Dusty Stevens]

Forester

 

[Willoughby]

It's LEUPOLD! dammit. NOT "Leopould"

my apologies fine sir but- my scope boxes from 88 are all in the attic, I think...

 

[Alex Wheeler]

Rotate the scope in the rings 90 degrees and see if it starts vertical stringing.

 

[Shawnba67]

Rotate the scope in the rings 90 degrees and see if it starts vertical stringing.

Genius!

 

[BIG D]

Replace firing pin spring

 

[mike a]

Genius!

How it on its side. Gangster style.