I drew a Ut Moose tag for last season and got excited to use my 375 Ruger on the hunt. I built the rifle especially for this hunt from a 7mm Rem that had a bad crown. Why change out the barrel if the crown is bad? Well bigger is better in my world of guns.

I sighted the gun in when I got from the gunsmith with a Leupold VX-I and it shot "okay" groups. I then put a Vaise brake on it and was excited about the reduction in recoil. Then I changed the scope to an older Burris FFII with a gloss finish to match the metal on the gun. Thats when the problems started.

The groups on the gun when from 1 MOA to around 8 MOA and would walk all over the paper! I would shoot it 3 times, lay it down while I shot another gun then when I shot it againg the point of impact was nowhere near where it was on the last group.

Bad scope? Suggestions?

So it shot OK with the Leupold and no brake.
Did you check accuracy using the Leupold plus Vais brake?
Or did you just pop off a few shots off-target to test recoil?
Unclear here.

If it was accurate with Leupold plus brake, but inaccurate with Burris plus brake,
that begs the question of bad mounts or bad scope with the Burris installed, of course.

I have seen adding a brake change POI by up to a foot at 100 yards.
Never an accuracy problem like you are having however.

If the barrel is thin and whippy, a heavy and long muzzle brake could alter the barrel harmonics enough to cause bad accuracy, like screwing a BOSS brake or muzzle weight on or off to different lengths.

Gotta know about the Leupold plus brake accuraccy before the Burris plus brake walking groups.

If the shots are all over the target, something is loose (or your barrel is badly fouled with jacket residue).

Check the action screws, then the ring screws. Tighten them if loose (do not over-tighten (if you hear squeaking, you're over-tightening).

If everything was tight, remove the scope, and check the screws on the bases. If they are tight (I always use blue LocTite on these screws), degrease the rings and re-mount the Leupold and shoot a group; if the gun shoots like it did before, the problem is likely with the Burris.

You can check the Burris by putting it on a different rifle of known accuracy; if that gun's shots go all over the target, send the scope back to Burris for repair.

George

The Leupold plus the Vais brake shot a 1 MOA group. When I changed the scope out to the Burris the first group was sub MOA then rest when to hell after that.

Just wondering if anyone else had similar problems with a Burris scope?

Your reticle has gone loose in the scope

m

No, but I know one of our Members has had two or three Leupold Vari-X IIIs go tits up on his .378 Wby. rifles.

The erector tubes bent under recoil.

Also, I watched a .340 Wby. scatter its shots across the target; the action screws had loosened under recoil, and four shots were enough to crack the stock between the lug recess and the magazine well.

I suspect loose action screws, rings or bases first; sometimes the screws loosen (or even shear) under recoil.

George

I have a Burris Sig. Select 1.5-6 on my Ruger African 375 R. No problems at all so far, but only about 50 rounds through this combo.

Hugh

Well, that's more clear.
Assuming the same rings and bases properly applied, and rifle otherwise OK,
only change was the scope, then the Burris scope must have given up the ghost.
I have only used two Burris scopes previousy, prefer the Leupolds.
Zero failures out of my two Burris scopes.
Three returns for warranty work free of charge on about fifty Leupold scopes in my life.
Somebody else got the Burris lemons not me.
Maybe you busted your Burris?

My 3 Leupold failures:
1. Broken reticle on a 2.5X M-8 on a .458/.338 Lapua Magnum: standard duplex was changed to heavy duplex, may have been a weak wire that finally gave under the pounding

2. Windage adjustment stopped working on a 6.5-20X VXIII, on a Cooper .223 single shot: don't know why, good as new now, after warranty repair

3. Power change ring tight from the beginning finally froze, stuck, won't turn, on a 3x-9x Leupold Centennial Edition 1907-2007 "special" Leupold: May have had some rough threads that finally galled tight, it is in Oregon now, being repaired.

quote:

Assuming the same rings and bases properly applied, and rifle otherwise OK,
only change was the scope, then the Burris scope must have given up the ghost.

+1 that is my thought as well.

Just pulled the gun out of the safe and checked everything over.

The scope bases and rings were tight.
The front action screw tightened 1/8th of a turn.
Looks like I'll be sending the scope back to burris.

Why not stick the LEU back on the rifle to confirm your groups go back to normal. If they are still all over the map, you will then know to look elsewhere.