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Hushko
05-02-2020, 01:01 PM
I’ve got a Savage Model 12BVSS in 223 Rem. I bought this rifle new 15+ years ago and never had the time to shoot it. Back then, I topped it with a Farrell 0 MOA picatinny mount, TPS steel rings (low) and a new Burris 6X-24X-44 Signature series scope. While sighting it in, I found that I ran out of elevation adjustment in the up direction - and I was only working at 50 yards. Everything was professionally mounted and not done halfway. I contacted Burris and they suggested their Signature rings with the Posi-Align inserts to get things on target. Today, I remounted the scope with the Signature rings and the 0 MOA inserts for a baseline. I also centered the elevation and windage adjustments, leaving an equal number of clicks in either direction. Test-firing at 100 yards, my 5-shot group was sub 1/2”. The group, however, was exactly 12” low and 13” left. Before I go and start playing with the inserts to get things centered, I was hoping to reach out to those who are much more experienced in this department to see if this is common. Thank you in advance for your input.

Texas10
05-02-2020, 01:46 PM
Do you have another scope that is known to be good you can swap out to eliminate the scope as the problem?

If not, set the gun up on the shooting bench and secure it. Remove the bolt and look down the bore, adjusting the set up until your bore is pointing exactly at the targets bullseye at 50 yds. Then without moving the gun, look into the scope. With the turrets at center, you should be pretty close to centered on the target. If not, start looking for reasons why not. It is not uncommon for Savage's to drill the scope mount holes off axis with the barrel. Leupold rings have a windage adjustment just for this purpose and that is what was put on my 12BVSS 223 to start.

However elevation is another matter. Since you'll never need 20 moa of down turret, it makes sense to set the scope/rings so that you all the up travel the scope has to offer.

One other question: Is it possible your rail is actually a 20 moa rail and not 0 moa? Mistakes get made, so measure carefully front and back. If it's canted, it's not 0 moa.

Change rings, change rail, change scope until you find the problem. BTW: That's a very good shooting model. Enjoy it thoroughly!

charlie b
05-02-2020, 03:50 PM
You've had a gun 15 years and have not fired it? I usually fire a weapon within a week of purchase and sometimes same day. Several within hours of acquisition.

My BVSS is much newer than that and seems to be fine. Vortex Viper scope. Std Warne rings and base. No big offsets needed.

I'd also check boresight and scope base alignment first. I usually boresight anyway when mounting a scope. I have a telephone pole right at 300yd from the garage I can use as an aimpoint that I can see through the bore.

Hushko
05-02-2020, 05:55 PM
Thank you for the great info Texas10! I did verify the mount and it measures at 0 MOA with no cant. Unfortunately, I don’t have another scope to try in order to rule out the optic. However, I’m thinking that maybe I could rotate the existing scope 90 degrees to see if the results are the same and don’t follow the rotation. And that’s great advice on adjusting the rings to retain more of the up adjustment - I didn’t think of that. The Burris insets are due in this week and I’m going to see if that will correct the alignment. Mis-aligned scope base mounting holes in the receiver was the direction I was originally thinking, but didn’t expect that they would be that far off. But after hearing about your experience, I’m thinking that this is possibly the case. Much thanks for your help!


Do you have another scope that is known to be good you can swap out to eliminate the scope as the problem?

If not, set the gun up on the shooting bench and secure it. Remove the bolt and look down the bore, adjusting the set up until your bore is pointing exactly at the targets bullseye at 50 yds. Then without moving the gun, look into the scope. With the turrets at center, you should be pretty close to centered on the target. If not, start looking for reasons why not. It is not uncommon for Savage's to drill the scope mount holes off axis with the barrel. Leupold rings have a windage adjustment just for this purpose and that is what was put on my 12BVSS 223 to start.

However elevation is another matter. Since you'll never need 20 moa of down turret, it makes sense to set the scope/rings so that you all the up travel the scope has to offer.

One other question: Is it possible your rail is actually a 20 moa rail and not 0 moa? Mistakes get made, so measure carefully front and back. If it's canted, it's not 0 moa.

Change rings, change rail, change scope until you find the problem. BTW: That's a very good shooting model. Enjoy it thoroughly!

Hushko
05-02-2020, 06:09 PM
Yeah, I know. Life just got in the way and most of my shooting time was spent building and firing custom pistols for my customers. Now trying to catch up on my own projects that have been neglected over the years. I shoot more AR-15 Style platforms, but never ran into this severe of a misalignment. The model 12 shoots great and groups terrific - just not in the right spot. I’m going to give the Burris posi-align inserts a try, since I already have that setup on hand. Thanks for your reply!


You've had a gun 15 years and have not fired it? I usually fire a weapon within a week of purchase and sometimes same day. Several within hours of acquisition.

My BVSS is much newer than that and seems to be fine. Vortex Viper scope. Std Warne rings and base. No big offsets needed.

I'd also check boresight and scope base alignment first. I usually boresight anyway when mounting a scope. I have a telephone pole right at 300yd from the garage I can use as an aimpoint that I can see through the bore.

Smokey262
05-02-2020, 07:06 PM
There is nothing wrong with the scope. I have had the exact same issue on every Savage centerfire rifle I have ever owned. It is caused by the front and rear tops of the receiver not being parallel and in the same plane, and if memory serves me right it is related to heat treating the front. If you remove the mount and put a straight edge across the top it is quite obvious.

The signature inserts work great, and permanently fix the issue. My recollection is that the back has to come up 0.010 and the front has to go down 0.005, but of course yours may be different. Center the scope's reticle, shoot it, then if its more than 5ish MOA out increase the posiline offset amount instead of dialing elevation., Note that the inserts can be inserted so that they are rotated slightly left or right to move the POI in two directions, say up and left.

Another thing you can do is use these to give the effect of a canted base for longer range shooting. Works great for this.

Robinhood
05-02-2020, 08:13 PM
About 17 years ago the actions were flat rear scope mounts. Is yours flat or round on the rear of the action?

Hushko
05-02-2020, 09:20 PM
Mine has the round-top receiver.


About 17 years ago the actions were flat rear scope mounts. Is yours flat or round on the rear of the action?

Hushko
05-02-2020, 09:25 PM
Thank you for the info!


There is nothing wrong with the scope. I have had the exact same issue on every Savage centerfire rifle I have ever owned. It is caused by the front and rear tops of the receiver not being parallel and in the same plane, and if memory serves me right it is related to heat treating the front. If you remove the mount and put a straight edge across the top it is quite obvious.

The signature inserts work great, and permanently fix the issue. My recollection is that the back has to come up 0.010 and the front has to go down 0.005, but of course yours may be different. Center the scope's reticle, shoot it, then if its more than 5ish MOA out increase the posiline offset amount instead of dialing elevation., Note that the inserts can be inserted so that they are rotated slightly left or right to move the POI in two directions, say up and left.

Another thing you can do is use these to give the effect of a canted base for longer range shooting. Works great for this.

kkeene
05-03-2020, 11:49 PM
I have seen this on several Savages also.

Looks like you got a good shooter! I have found that accuracy typically improves over the first 50 rounds.

mnbogboy2
05-06-2020, 12:15 AM
This is a common issue with factory barrel nut rifles. However the Burris inserts will get you where you want to be.
There are several causes for this including; bore curvature, and misaligned scope base screw holes. The biggest contributor that I have witnessed is the "stamped" recoil lugs and barrel thread "fit". The stamped lugs are not flat nor parallel side to side. Combine this with a loose thread fit and the torque on the barrel nut will force the barrel to seek its home in any random direction. This is often noticed with the barrel not parallel in the barrel channel.
Combine this misalignment with an excessive bore curvature and there have been instances where the rifle cannot be zeroed.
Clocking curvature while maintaining optimum headspace is a pita with a nut barrel. I've done it several times but requires two or more installs.
If saami headspace tolerance is acceptable near 12:00 clocking can usually be achieved 50% of the time just by adjusting the recoil lug thickness.

The Burris mounts are a good answer in most cases.

Good luck.

Hushko
05-07-2020, 02:46 PM
Update: Today I installed the new Burris rings with the Posi-Align inserts to try and get my model 12BVSS 223 on target. Before starting, I centered the windage adjustment and set the elevation so there was 3/4 of the up adjustment available. After several adjustments, the best that I was able to obtain using the posi-align inserts alone was a horizontally centered, but 6” low group. This was achieved by using the 20 MOA insert in the rear, to raise the rear of the scope upward and slightly to the right. And then using the 10 MOA inserts to move the front of the scope downward and to the left. With the inserts being slightly rotated to compensate for the windage, I’m guessing there’s around a 25+ MOA vertical change and this rifle is still shooting 6” too low. I’m thinking now of changing out the Farrell 0 MOA base with a 30, or even a 40 MOA base. Has anyone seen a receiver that was out to this extreme?

sharpshooter
05-07-2020, 06:22 PM
I've corrected many out to this extreme. It's usually a combinations of all the factors mentioned above.

Hushko
05-07-2020, 09:38 PM
Thank you for the info. I’m hoping a more simplified route with variations in rings and bases will do the trick. Accuracy-wise, this rifle has performed well - so at least that’s good news.


This is a common issue with factory barrel nut rifles. However the Burris inserts will get you where you want to be.
There are several causes for this including; bore curvature, and misaligned scope base screw holes. The biggest contributor that I have witnessed is the "stamped" recoil lugs and barrel thread "fit". The stamped lugs are not flat nor parallel side to side. Combine this with a loose thread fit and the torque on the barrel nut will force the barrel to seek its home in any random direction. This is often noticed with the barrel not parallel in the barrel channel.
Combine this misalignment with an excessive bore curvature and there have been instances where the rifle cannot be zeroed.
Clocking curvature while maintaining optimum headspace is a pita with a nut barrel. I've done it several times but requires two or more installs.
If saami headspace tolerance is acceptable near 12:00 clocking can usually be achieved 50% of the time just by adjusting the recoil lug thickness.

The Burris mounts are a good answer in most cases.

Good luck.

Smokey262
05-07-2020, 09:45 PM
You could try making and installing a shim under the rear of the base

Hushko
05-10-2020, 12:28 PM
Just as you suggested, I removed the base and ran a straight edge across the top of the receiver and it’s definitely not on plane. The straight edge rocks front to back, leaving about a 0.006” gap. I’ve got a Farrell Industries 20 MOA base on the way and will bed the rear with JB Weld. Thanks again for your input.


You could try making and installing a shim under the rear of the base

Robinhood
05-10-2020, 02:05 PM
I've corrected many out to this extreme. It's usually a combinations of all the factors mentioned above.

Wait until somebody buys/finds one that somebody put a lever through the ejection mag ports to remove the barrel.

sharpshooter
05-11-2020, 11:27 AM
I've straitened several that were that way, one had almost a quarter turn twist.

Hushko
05-12-2020, 09:09 PM
The Farrell 20 moa base bedded to the receiver at the rear. Corrected the elevation problem. The gun still shoots way left, and I have to use most of the windage adjustment to correct it. Nonetheless, it’s on target at 100 yards and shooting 1/2” groups - which is good for me. I took off the Burris Posi-Align rings, which would correct the windage issue. I just have trouble using Chinese parts. Thanks again for everyone’s input. Time to shoot this thing!

Smokey262
05-12-2020, 09:17 PM
Nice going! Are those rings really made in China now?