One piece vs two piece mounts

Brian564

Active Member
Joined
Dec 8, 2014
Messages
31
Is it true that one piece mounts give the rifle more accuracy than two pieces mounts? I've only used one piece mounts so far and never thought about the difference, so I'd appreciate a crash-course on this subject and why would one type be more accurate than the other. Thx
 
Well with me it is not about accuracy when choosing a mount it's about protecting my investment in the very expensive scope that I'm going to mount. I use Near Picatinny rails almost exclusively bedded to the receiver by my smith. Then a good set of rings like Near or Seekins.

Once the scope is mounted properly accuracy is just part of the reward. The real reward comes because there is virtually no stress introduced into the scope thru the mount that could cause damage or issues and that would have to add to consistent accuracy in the long run. Also a rail does add some strength to the receiver needed or not.
 
I agree with Kcebc that it's not about accuracy but much more importantly it's about maintaining a straight center line through the very expensive scope. Both two piece mounts and one piece rails deserve to be checked for alignment of rings when those are installed. Lapping may be necessary in either case. But, in my experience, more lapping is usually required with two piece mounts. I also like the increased rigidity of a one piece mount. Properly bedded and set into place, they just stay where they're put.
 
This is highly embarrassing, but I am quite a newbi and don't get it. Aren't two pieces rails properly centered from factory, each with two screw holes to guarantee it wouldn't be tilted when inserted on a rifle? What would cause them to be off center? Sorry for the beginner questions.
 
This is highly embarrassing, but I am quite a newbi and don't get it. Aren't two pieces rails properly centered from factory, each with two screw holes to guarantee it wouldn't be tilted when inserted on a rifle? What would cause them to be off center? Sorry for the beginner questions.

In theory they should be but in practice the tolerances of the rifle receivers are generally pretty poor so when you bolt the bases/mounts to them they can be off quite a bit.

If rifles were better made then everything should line up perfectly, but mass produces rifles as a rule are pretty sloppily put together and thing can be off quite a bit. Screw holes are often drilled crooked and the contouring of the bridges of the receivers is often not to specifications so the bases don't lie flat on the receiver.

That's why good gunsmiths are so in demand. If the factories built rifles the way they should be built then there wouldn't be nearly as much work for gunsmiths in fixing them.
 
The claim of getting better accuracy with the one piece is that the single unit can add rigidity to the receiver over the 2 piece. I have used both types and cannot really say that I have seen a difference in accuracy if the contact surfaces between the scope, mounts and reciever are properly mated and aligned. Strength and durability is a different story. I think the one pc. Steel pic rail and rings like the NF, Mk4, and similar designs are superior in this area. I have had alloy two piece mounts get knocked out of alignment with hard contact to the scope.
 
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Id pretty much agree with Greyfox. In theory one pc. bases should be a more solid
setup. Fact is i havent changed some of my mounts such as some very old 2 pc Weavers. Ive also invested in allignment tools several years back and havent found
the problems with allignment on factory receivers claimed by some. The one pc.
piccitinny base has an advantage in that it allows for a wider range of scope placement and also has an advantage with shorter scopes.
Some of the one pc. bases only use 3 screws so that argument could be raised also.
Allignment seems more critical nowdays due to many scope makers using tin foil for the tube. Same goes for torquing screws on mounts. Tighten them down hard on an
old Leupold or a Nightforce but try that on a Vortex and it will fail. Fact is it will fail
anyway but thats another argument.
 
.........
Same goes for torquing screws on mounts. Tighten them down hard on an
old Leupold or a Nightforce but try that on a Vortex and it will fail. Fact is it will fail
anyway but thats another argument.


I've actually personally seen two sets of MK4 rings fail (eventually) after being over torqued....



I wish there was a like button for posts/threads.... It's one piece or bust for me, rigidity & optimum alignment are paramount.



t
 
...Ive also invested in allignment tools several years back and havent found the problems with allignment on factory receivers claimed by some....
Are you using Kokopelli alignment bars? They give the full story. Pointed alignment bars show lateral misalignment between the rings, but do not show angular misalignment.
 
+1 on what kcebcj said . Can't speak for other Rifles and I do like old Rem 700s , but I have mounted Bases and Rings on about 2 dozen 700s for myself and friends . Just for kicks I always start out with 2 piece Bases . When the owners see how the front to back Rings Align using Scope Pointers , they always Opt for one Piece Bases .
 
I've actually personally seen two sets of MK4 rings fail (eventually) after being over torqued....



I wish there was a like button for posts/threads.... It's one piece or bust for me, rigidity & optimum alignment are paramount.



t
Well breaking screws due to too much muscle can be an issue also ill admit.
But you wont be breaking many at the 15 to 20 inch pounds reccomended on
some of the scopes in order to keep the turrets working.
 
Well breaking screws due to too much muscle can be an issue also ill admit.
But you wont be breaking many at the 15 to 20 inch pounds reccomended on
some of the scopes in order to keep the turrets working.


Don't get me wrong, I whole heartedly agree with you. There's a reason they come with a torque value printed on the packaging. I guess the installer thought more is better.:cool:



t
 
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