About a month ago my granddad finally got his old 300 Weatherby back from his cabin in Colorado. This particular Weatherby is a German made Mark V Deluxe topped with a Swarovski 6-18x50mm scope. He's had this rifle for about 50 years and hunted all over the continent with it, as well as in Africa.

During his last hunt on Santa Rosa island a few years back, he discovered he couldn't sight it in. For whatever reason, it wouldn't shoot straight. He couldn't get it to group, and niether could anyone else in his group. Frustrated, he kept it at home from then on.

He let me borrow it to see if I could figure out what's wrong. Long story short, it was shooting 6 or 7 inches to the left and 4 inches low at only 25 yards. I tried to adjust the scope, but I maxed out the adjustments and it was still shooting low and to the left. At 50 yards, I discovered something else: the bullet holes were oblong, not circular. However, using newer ammunition fixed this issue.

I took the rifle to a gunsmith, who believed it was an issue with the scope. He fixed something with the scope mount and boresighted it for me. Today I shot it again at 25 yards, and once again it's shooting over 6 inches to the left at that distance.

I have no idea what to do now. Any idea as to what's causing this issue?

I would still be suspicious of the scope. Once they fail on me, I never do completely trust them again. If the gun is consistently shooting low and left, I wouldn't think its a gun issue. If the hits were all over the place, then yeah, possibly the gun is at blame. I would try a completely different scope and rings. Eliminate the "upper" part all together. Not saying go spend a bunch of money to do this, but if ya have another set of this stuff available, that would be my first idea. At least that way you eliminate all possibility of scope issues. I am by no means a gunsmith, and there are others on here much more qualified than myself, so take my idea with a grain of salt.

Other than that, I wouldn't have a clue...

I think I have an old Leupold 3-9 power scope lying around somewhere. Might have to put that on the Mark V and see what happens. I'd hate to think my granddad spent that much money on a Swarovski only to receive one with a defect.

OH OUCH!!! You didn't say it was a Swarovski earlier!! Man now I REALLY hope that isn't the problem!!!

Maybe its the rings or base... hopefully!!!!

Is the crown ok?

Scope

First suspect is the scope or...... mounts. How is it mounted?

After you eliminate any funny business with the scope and or mounts place the rifle in a gun vice. Check your adjustments on a piece of graph paper. See if it is crooked on the gun. Part of owning good optics means making sure they are straigh with the gun. Find out how many minutes of windage and elevation are built in. If you are all the way against one side with the adjustments you have found the problem. Remove the scope and using the simple cut two "V" in a box method re-center the cross hairs if you stck it back on the rifle and it is off as far as it appears to be your mounts are crooked.

Muzzle crown. The gun smith should have caught it if it was bad but I have seen muzzle damage do some crazy things. The problem may just require a new crown.

Mount new scope and check mounts when you have it apart.

You didn't mention checking the barrel bedding and action screws .If it is consistently left check the bedding .Using a dollar bill see if you can slide it between the barrel and stock,my guess is the stock is touching the barrel somewhere on the right side causing it to shoot left. If you pull the stock off the gun sometimes you will see the rub mark. Check the obvious things first before blaming the scope.If its touching a bit of sanding will help,sand enough to get free passage of the bill,then reseal the wood. Even a slight touching of the stock forend on the barrel can make one shoot hell west and crooked and cause all kinds of grief.

Ditto.

Cleaned it lately?

My first thought would also be the sighting system, but the key holing at 50 yds suggests there may be other issues.

Any updates on the Weatherby problem yet? The bedding check only takes a minute and a dollar bill.You can also lock the gun down in a vice or notched cardboard box. Set up a white paper with a grid for reference then turn the scope adjustment knobs while watching thru the scope. If the scope is tracking left and right it should be ok and the problem is elsewhere.

I couldn't get a dollar bill between the barrel and stock. It stopped about three inches down.

It's not the adjustments on the scope that are the issue. It'll adjust the crosshairs without any problems. The issue is the bullets are hitting so far away that I can't adjust the scope enough to get them to hit where the crosshairs are aiming. If the bullets are hitting 7" left at 25, then they'd hit 28" to the left at 100 yards. Since that scope has 1/4 MOA adjustments (supposedly), it would require over 100 clicks of adjustment, which it is simply not capable of doing.

We'll see what happens when I put the Leupold on it. I'll get it on the rifle today and shoot it tomorrow if the weather clears up.

If the bill stops 3 in down you have a warped or swelled stock.There should be a mark on the inside where the barrel is touching. Before you put on another scope pull the stock and sand or scrape the place where the stock is hitting the barrel
until a bill will go most of the way to the bottom then reseal.
They will shoot away from where they touch. To prove this take another rifle that you know shoots and wedge a paper match between the stock and barrel 3 in. down and shoot one shot,then move the match to the other side of the barrel and shoot again.
Then remove the match and it goes back to zero. If you just put on another scope without fixing the problem the rifle will drive you nuts changing zero every time the humidity changes and the stock dries out or absorbs moisture .

The good thing is both Weatherby and Swarovski are very good about taking care of customers so if you can't figure it out send both back to the manufacturer for inspection. I would especially do that with the MK V rather than take a chance on a hack screwing it up. Those old MK V's are a work of art and usually have top grade wood. You might see if the Weatherby shop will bed the gun for you.

Some rifles have an intentional pressure point about three inches back. Doesn't mean that is still not the problem.

Wow. It's been a long time since I've dealt with that gun, and even longer since I've updated.

Well, the Leupold fared no better, with the bullets hitting almost the same distance from the point of aim as when the Swarovski was on it. After seeing that the issue wasn't the original scope, and out of ideas, I put the gun away and simply forgot about it for the past few months. This afternoon though, my dad and I were going to the local outdoor store to have my dad's bow adjusted, and he remembered the Weatherby. We were going to take it with us to leave with the gunsmith, to see if he could figure out what was wrong. Just as we entered the store, my dad met an old friend of his and explained the situation to him. The guy looked over the gun and showed me a pair of screws on opposite sides of the rear base. He said they're for orienting the rear base, which would slightly rotate the scope. I don't know if it will help, but I'm going to try it this weekend. Maybe I can finally fix the problem and return the Weatherby to my grandfather in working order.

That is a windage adjustable, a.k.a. standard, base/ring set. Prior to sight in one should center the crosshairs in the scope and then adjust the windage with the scope base to get close to center before adjusting the turret on the scope. This is one situation where a picture would have been worth a thousand words.

Sounds like you have Buehler Scope Bases and Rings - they were very popular decades ago - especially for the "big bores".

The rings should have spacers in them to fit the scope - important to have those spacers to fit different scopes but the spacers currently installed should be for your Swaro.

The Buehler line was purchased by Weatherby years ago and I believe they are no longer available.

No idea on why the keyhole but all the Weatherby's Mark IV's I've ever owned had a forearm pressure point, so that is not part of your problem. I tried free floating a Mark IV and it didn't improve accuracy at all - burning all that powder per shot makes for a hot barrel and after the 3rd to 5th shot in fairly rapid session you will start seeing a "pattern" as opposed to a group.

You can also shim the rear base if needed.

I've been moving the windage adjustment and it really helped. The only problem now is that, since it's almost 90 degrees and I've fired about 10 rounds in relatively quick succession, the barrel is too hot to touch and is producing patterns instead of groups. I'm going to let the barrel cool for a while, then shoot a few more times to see where the bullets are really going at 100 yards.

took a family member on a hunt a number of years ago and let them use my 300WB. The shots were all over at 50yds. After checking found the mounts were loose. Good luck...

Why not just try a Weaver style base and Burris Signature Z rings.

Even if the base holes are off you can buy the corrective plastic offset bushings and not have to adjust the scope hardly at all.

I think I've fixed it. When I have time, I'll take it out to see if I can finish sighting it in. Running out of Weatherby bullets though, and I'd rather not use handloads meant for another gun in it.

180 grain Ballistic Silvertip with 84.5 grains of standard 7828 behind it loaded as long as your magazine box will take it. It was exceptionally accurate in my guns and the deer hated it. I think I killed around 180 whitetail with that load before I retired the rifle. Would have to go check the old books but it was in the 180-185 range and distances were from 10 yards to 675 yards. Used to shoot one of the rifles out to 1200 yards and it was a good shooter with that load. I tested about 30 different bullets in those guns and that is the one I settled on. Works well at those velocities that it can generate and it holds together. I never had one fail which is something I can't say about some of the other bullets. the old 180 Triple shock from Barnes is another really good one that had amazing accuracy.

I spoke too soon, it seems. I took it and a couple of other guns out this afternoon, but the Weatherby was back to giving me trouble. Bullets hitting vastly different spots at 50 yards, and the 200 grain Partitions were key-holing. I'm running out of bullets for it, too, so I decided to quit. At least it's hitting closer to the point of aim than before.

Apparently, this one was made in Germany and had a 1 in 12" twist rather than the 1 in 10" twist in use today. I wonder if that could be throwing them off so badly.

It may be well worth trying some shorter bullets with that twist.

When I get back into reloading, I'll see if I can craft a 150 grain handload for it.

Be really careful with 150 grain bullets. Most of them out there will literally explode when they hit and half of the time, they will not exit. Sort of a shrapnel grenade to be honest. I would look at 165 partitions maybe. They will hold up and there are some good 165 grain bullets out there that would work well. Most 150s start to come apart in a 300 Win mag, let alone a WBY. They are great for 30-06 and 308s though. When you deal with guns that produce the velocity that the WBY can and the pressures, you have to start really looking at bullet construction, not just weight. The 165 will shoot flatter at extended ranges than the 150 as well, holds its steam better. Doesn't seem like 15 grains makes a difference but its pretty noticeable.

Has anyone else shot it that is comfortable with the gun just to rule out a flinch? The blast on the big guns is enough to make some folks snatch the trigger like a shotgun rather than a rifle some days. May be worth trying if you know someone that is truly accustomed to shooting heavier kicking rifles just as a check.

Maybe. I didn't feel like I was, but it's a possibility.