QD mounts on .375 and .458 Lott Mauser 98s

[SRvet]

Good afternoon ladies and gentlemen.
We have just finished a very enjoyable and successful safari with Jamy Traut Safaris in Namibia and took a variety of dangerous and plains game. We did encounter an issue with one of the groups .375 Mauser rifles with an inability to maintain zero, fortunately this was discovered when checking zero and not on a hunt so did not impact anything in a meaningful manner. I am suspicious that this may be due to the non detachable Leupold STD mounting system being inadequate for a regular diet of 300 grain ammunition. This system is the one with a dovetail on the front ring and the two windage screws on the rear base.
Can I ask which QD bases/rings have proved reliable to you all on more stoutly recoiling calibres from .375 H&H up?

 

[baxterb]

for off the shelf you’ll pretty much start (and finish) at Talley. For over 375 consider going to 8-40 screws or even custom bases for perfect alignment. And when mounting the Rings make sure you push them hard into the front shoulder before clamping them.

 

[Ontario Hunter]

So far this setup has not failed on my 404 98 Mauser. Rings are "low" Warne QD and the base is a Weaver 1-piece that may now be discontinued. Originally I used a 1-piece CCOP USA base from SARCO which worked fine but then I switched from 1" tube scope to a 30mm tube and the Weaver base is lower. Because my rifle is built on a Czech military gun it retained the stripper clip hump. These builds often employ 1-piece scope bases with three screws, two ahead on the locking ring and one behind the hump. My action was already tapped for three screws when I acquired it.

One-piece scope base is obviously more rigid and provides perfect alignment of two rings. Lapping the rings should not be necessary. Pic rails are somewhat different. They typically have slots for rings end to end. These one-piece mounts have no slots over the loading port where part of the base is cut away to provide better access when loading. I have never had any problems loading either brand of base (my plains game 30-06 03A3 also wears a SARCO 1-piece base). They always return to zero. When reattaching the scope just make sure the rings are pushed all in the way forward in the slots before tightening the clamps on rings.

Mauser top and Springfield below it

Weaver base on Mauser only has two slots for rings. Another advantage to most 1-piece bases/rails is they allow a variety of scopes to be attached in a variety of ways. Short tubes or eye relief issues are easily accommodated by placing the rings wherever needed.

 

[roklok]

I prefer Warne over Talley, but Talley is certainly a quality product and has a lot of fans. I have Warnes on two .375s and they have been great. Return to zero and very robust, also the levers are easily oriented to your preferred angle.

I strongly prefer two piece bases over one piece for a few reasons, they are lighter, they allow more access for loading and ejection, they attach to the receiver with 4 screws instead of three. In my experience a one piece base does not guarantee perfect ring alignment, if the receiver is not true the one piece base will actually flex to conform to receiver when screws are tightened and misaligned rings can still occur. One piece bases are great for determining if receiver mounting surfaces are aligned, but if they are not they should be shimmed under the base so the base does not twist when screws are tightened. My .458 came with a one piece base, when the rear screw was removed the base sprung upwards a few thousands with a gap under base. It was in a bind when all screws were tightened.

 

[Adam Stevens]

for off the shelf you’ll pretty much start (and finish) at Talley. For over 375 consider going to 8-40 screws or even custom bases for perfect alignment. And when mounting the Rings make sure you push them hard into the front shoulder before clamping them.

I prefer Warne over Talley, but Talley is certainly a quality product and has a lot of fans. I have Warnes on two .375s and they have been great. Return to zero and very robust, also the levers are easily oriented to your preferred angle.

I strongly prefer two piece bases over one piece for a few reasons, they are lighter, they allow more access for loading and ejection, they attach to the receiver with 4 screws instead of three. In my experience a one piece base does not guarantee perfect ring alignment, if the receiver is not true the one piece base will actually flex to conform to receiver when screws are tightened and misaligned rings can still occur. One piece bases are great for determining if receiver mounting surfaces are aligned, but if they are not they should be shimmed under the base so the base does not twist when screws are tightened. My .458 came with a one piece base, when the rear screw was removed the base sprung upwards a few thousands with a gap under base. It was in a bind when all screws were tightened.

I ended up going with warne, I forget my gunsmith who did the work, there was something not jiving with talley and the Leupold 2.5x8 and also the talley bottom didn't allow the factory iron sights to be functional. Warne qrw low ones worked great.

And huge tip, I always applied pressure to the scope towards buttstock vs barrel but I know now that's wrong. The inertia of the gun firing, forced the scope forwards. Towards end of barrel. I have no idea why I never realized that but glad a few posts on AH made me realize my mistake.

 

[baxterb]

I ended up going with warne, I forget my gunsmith who did the work, there was something not jiving with talley and the Leupold 2.5x8 and also the talley bottom didn't allow the factory iron sights to be functional. Warne qrw low ones worked great.

And huge tip, I always applied pressure to the scope towards buttstock vs barrel but I know now that's wrong. The inertia of the gun firing, forced the scope forwards. Towards end of barrel. I have no idea why I never realized that but glad a few posts on AH made me realize my mistake.

depending on where the front mount is drilled, it can be tight on that 2.5 x 8 because of the tube clearance. That’s why I went to a 1.75 x 6 - there is a teeny bit more room. All good, glad it’s sorted out.

 

[Tim Blackwell]

I've had a good run with both Warne and Leupold QRW on my Mk.X 458WM.

 

[Adam Stevens]

Also, if Warne or Talley arent allowing site picture of the factory Irons, if that matters to you" weaver style work aswell. This is weaver bases and leupold qrw on .375 sako mauser

 

[BeeMaa]

I used Warne low QD rings on my 375H&H CZ550 with a Leupold 1.5-5x20 scope. Scope was removed on a regular basis for cleaning and travel with 100% return to zero. These are two piece rings that mate directly to the dovetailed CZ550 double square bridge receiver with a notch on the left rear bridge. Whenever mounting the scope, I would apply forward pressure to the scope while tightening the rear ring first, then the front. Perfect every time.

 

[Ontario Hunter]

Also, if Warne or Talley arent allowing site picture of the factory Irons, if that matters to you" weaver style work aswell. This is weaver bases and leupold qrw on .375 sako mauser

View attachment 770804

Those rings look quite high. And the irons look quite low. If you can see them over those Weaver bases, it must be just barely. Are the irons attached with screws? Front sight pushed in from side or slide in from front of ramp?

 

[375er]

I have used the Leupold QD mounts on a 375 for about 30 years with zero problems or complaints.

 

[SRvet]

I have used the Leupold QD mounts on a 375 for about 30 years with zero problems or complaints.

Are those the ones with the cylindrical posts and the cam locks? If so I have them on my .375 and 458 Lott. The .375 seem ok but the cam locks on the Lott may have deformed under recoil hence the search for something more robust!

 

[roklok]

Leupold makes two styles of QD rings and bases, one is essentially the same as Warne's and the other has the small round studs on rings with levers on bases. I have the latter style on a third .375, and the jury is still out on those. They definitely do not seem as robust as the Warne style.

 

[375er]

Are those the ones with the cylindrical posts and the cam locks? If so I have them on my .375 and 458 Lott. The .375 seem ok but the cam locks on the Lott may have deformed under recoil hence the search for something more robust!

Well, all I can tell you is that I have not had a problem with them in 30 years and my rifle by no means a safe queen.

 

[Fixfire]

I have used the Leupold QD mounts on a 375 for about 30 years with zero problems or complaints.

Same, except 10 years. M70.

 

[JG26Irish_2]

Leupold makes two styles of QD rings and bases, one is essentially the same as Warne's and the other has the small round studs on rings with levers on bases. I have the latter style on a third .375, and the jury is still out on those. They definitely do not seem as robust as the Warne style.

I have a set of the latter style with the round studs on the rings and the levers on the bases. These are used on my Sako 85 in 338wm. While not a 375HH, I have two of those as well and the 338's felt recoil is every bit as much as the 375's. This due in part to the little Sako being a pound or two lighter. I am not a QD mount fan but these were the only steel rings I could find in 34mm that would fit the Sako mounts.

I have had this rig for about a year and it is performing well. I have a 1-8x and a 4-16x scope that I use and swap on the rifle. The rings seem to have performed well enough. There was a point when the Sako mounts shifted slightly as they settled onto their dove tails but that was not a fault of the rings. Since then, I have had good results and took a 600lb Nilgai and a coyote while hunting with it in Texas back in the winter. Accuracy has been adequate but not stellar. Which makes me wonder if the rings are a cause?? They seem very tight so, I doubt this. More likely just the limitation of the rifle. 100y groups are still 1-1.5" depending on loads which is OK but pretty poor for a typical Sako. I have two others that are both 1/2 moa rifles.

 

[Ontario Hunter]

I prefer Warne over Talley, but Talley is certainly a quality product and has a lot of fans. I have Warnes on two .375s and they have been great. Return to zero and very robust, also the levers are easily oriented to your preferred angle.

I strongly prefer two piece bases over one piece for a few reasons, they are lighter, they allow more access for loading and ejection, they attach to the receiver with 4 screws instead of three. In my experience a one piece base does not guarantee perfect ring alignment, if the receiver is not true the one piece base will actually flex to conform to receiver when screws are tightened and misaligned rings can still occur. One piece bases are great for determining if receiver mounting surfaces are aligned, but if they arie not they should be shimmed under the base so the base does not twist when screws are tightened. My .458 came with a one piece base, when the rear screw was removed the base sprung upwards a few thousands with a gap under base. It was in a bind when all screws were tightened.

The bigger issue may be running out of turret adjustment if the screw holes for 1-piece base are not in line or level. I had this problem when changing to a 1-piece base on my Springfield 03A3 (actually, a continuation of same problem with Weaver bases). Bases for 03A3, whether one or two piece only have one screw in the rear because that end is mounted on the male dovetail for the original military sight. Those dovetails were not very carefully machined, as evidenced by the rough machining marks on top. My dovetail was apparently machined higher than normal. Both the Weaver bases my dad put on it and the one-piece SARCO base I replaced them with in 2018 required shimming on the locking ring or I ran out of elevation adjustment on the scope (two scopes actually). The more sensible solution would have been to file down the dovetail before I sent the rifle off for rebluing (duh!). I used a plastic shim made from plastic shotgun shell hull to level out the base. Perhaps this year I will do it right and file down the dovetail. Cold bluing to clean it up will probably suffice underneath the base. I should add that the rings did not mark scope tube so it would seem there was not significant twisting of the one-piece base. The scope was simply tilted down too far.

A bit of a derailment but important. Once a long time ago I was advised to apply a thin coat of rubber cement to underside of bases before screwing them onto receiver. This supposedly sealed them just enough to prevent moisture from getting underneath and rusting the receiver (my bases back then were aluminum Weaver). Anyone else heard that?

 

[450 Dakota]

I run Talley from 340 Wby to 458 Lott on Winchester 70.

 

[375er]

Wait. You are criticizing and questioning the Leupold STD mount with the front dovetail and the rear screw windage mount then reversing and bashing the QD mount? Am I reading this right?

 

[Schüler Jumbo]

Griffin & Howe Side Mount: