Scope bases

[Trevor1837]

How important are scope bases if your rifle is grooved for scope mounts? Do they improve accuracy? What do they really do? Sorry for the stupid questions

[BETH]

hey trevor don't worry not a stupid question i'm with u i don't know the answer so we will wait till someone comes along

[JLA]

scope bases expand the mounting systems adaptable to your firearm. Not everything will fit on a tip off groove and vice versa. Having a rifle set up for either/or allows you to choose from the entire gammut the mounting system you want.

Careful what you pick though. Scope mounts for the most part will get the job done. But just to illustrate the differences from one system to the next, I had a lapped leupold one piece steel set up on my savage/CBI, I switched to a DNZ Gamereaper mounting system. The DNZs guarantee '0' tolerance, so perfectly straight you dont need to lap them, and they are 'Dead NutZ'.. After mounting my Nikon into the DNZ I discovered the top of the line Leupold set up was putting a 6 MOA bind on my scope. Meaning, even after lapping to ensure the rings were straight, the rear ring was lower then the front enough to cause a foot elevation at 200 yds after switching to the DNZ. SHoulda known something was up when i had to remove and reset 'Zero' on the target turrets of a 400 dollar scope after mounting in the Leupold set up.

Bottom line, If they make a DNZ system for your rifle, BUY ONE. Nuttn better on the market IMO..

[JLA]

BTW, Im gonna move this over to Tech Q & Info forum.

[reynolds357]

Originally Posted by JLA

scope bases expand the mounting systems adaptable to your firearm. Not everything will fit on a tip off groove and vice versa. Having a rifle set up for either/or allows you to choose from the entire gammut the mounting system you want.

Careful what you pick though. Scope mounts for the most part will get the job done. But just to illustrate the differences from one system to the next, I had a lapped leupold one piece steel set up on my savage/CBI, I switched to a DNZ Gamereaper mounting system. The DNZs guarantee '0' tolerance, so perfectly straight you dont need to lap them, and they are 'Dead NutZ'.. After mounting my Nikon into the DNZ I discovered the top of the line Leupold set up was putting a 6 MOA bind on my scope. Meaning, even after lapping to ensure the rings were straight, the rear ring was lower then the front enough to cause a foot elevation at 200 yds after switching to the DNZ. SHoulda known something was up when i had to remove and reset 'Zero' on the target turrets of a 400 dollar scope after mounting in the Leupold set up.

Bottom line, If they make a DNZ system for your rifle, BUY ONE. Nuttn better on the market IMO..

I got tired of lapping rings so I started using Burris signature.

[JLA]

I have tried them all. Including Burris signature zee. Nothing holds a candle to DNZ system.

[reynolds357]

Originally Posted by JLA

I have tried them all. Including Burris signature zee. Nothing holds a candle to DNZ system.

I would beg to differ. Signature is much more versatile.

[JLA]

I wont argue with you there. but I dont look for 'versatility' when I mount a scope to my rifle. I look for Dead Nutz precision...

[reynolds357]

Originally Posted by JLA

I wont argue with you there. but I dont look for 'versatility' when I mount a scope to my rifle. I look for Dead Nutz precision...

I like to play with my elevations. Sometimes I find that mounting parallel to the bore works well for a rifle. Other times, I find that mounting off vertical parallel works better. I have found that playing with the alignment angle can greatly flatten perceived trajectories relative to point of aim. I used to shoot with a Redfield engineer who explained the physics of it to me, but it kind of flew over my head. All I really found out was you can take some rifles and some scopes and get the scope and bore off vertical parallel to each other and you have a rifle that perceivebly shoots flatter than one mounted parallel. I assume you could do it with any rifle if you messed with it long enough to figure it out.

[JLA]

All your talking is putting a cant into the mounting system to squeeze extra range out of your scope. I would much rather invest some money into a solid precision machined mounting system with the cant machined in.

Changing a scopes angle relative to the bore doesnt make the cartridge the rifle is shooting shoot any flatter, it changes the POA so that you elevate the weapon to account for the extended range, thus saving the adjustment the scope has built in for getting on target at longer ranges.

Too much guesswork for a set of separate bases and rings. Much easier when the MOA cant is built in.

And for those wondering, Yes you can use a 20 or 25 MOA cant base with a scope at close range (inside 100 yds) all the cant does is move 'zero' to the bottom of the down adjustment so you have twice as much 'up' adjustment to compensate for bullet drop for shooting long range.

[Trevor1837]

Originally Posted by JLA

scope bases expand the mounting systems adaptable to your firearm. Not everything will fit on a tip off groove and vice versa. Having a rifle set up for either/or allows you to choose from the entire gammut the mounting system you want.

Careful what you pick though. Scope mounts for the most part will get the job done. But just to illustrate the differences from one system to the next, I had a lapped leupold one piece steel set up on my savage/CBI, I switched to a DNZ Gamereaper mounting system. The DNZs guarantee '0' tolerance, so perfectly straight you dont need to lap them, and they are 'Dead NutZ'.. After mounting my Nikon into the DNZ I discovered the top of the line Leupold set up was putting a 6 MOA bind on my scope. Meaning, even after lapping to ensure the rings were straight, the rear ring was lower then the front enough to cause a foot elevation at 200 yds after switching to the DNZ. SHoulda known something was up when i had to remove and reset 'Zero' on the target turrets of a 400 dollar scope after mounting in the Leupold set up.

Bottom line, If they make a DNZ system for your rifle, BUY ONE. Nuttn better on the market IMO..

I'm looking for a mount for a marking xt-22 rifle, DNZ has a mount for the marlin 925 which is basicallyy the same rifle, will this work? Thanks for the help.

[reynolds357]

Originally Posted by JLA

All your talking is putting a cant into the mounting system to squeeze extra range out of your scope. I would much rather invest some money into a solid precision machined mounting system with the cant machined in.

Changing a scopes angle relative to the bore doesnt make the cartridge the rifle is shooting shoot any flatter, it changes the POA so that you elevate the weapon to account for the extended range, thus saving the adjustment the scope has built in for getting on target at longer ranges.

Too much guesswork for a set of separate bases and rings. Much easier when the MOA cant is built in.

And for those wondering, Yes you can use a 20 or 25 MOA cant base with a scope at close range (inside 100 yds) all the cant does is move 'zero' to the bottom of the down adjustment so you have twice as much 'up' adjustment to compensate for bullet drop for shooting long range.

I am well aware of putting cant into a scope to extend the range the scope can adjust to. You will also find that when you do this, with some scopes,the observed trajectory is flatter at lesser ranges. You are modifying where the line of sight of the scope and the bore intersect. When you compensate for it with the scope, at shorter yardages, you do not have to aim over nearly as much. It has to do with the physical effects of the angle of the erector. The downside is when you put extreme angle on many erectors you cause the scope to not adjust well and and hold zero. I discovered it by accident and then the engineer explained to me why it worked. I had set up a .308 for 1000yd.(big mistake) Instead of taking the $130 elevated base off I decided I would just see if my scope had enough adjustment to bring it down to a 200 yard zero. What I discovered was my .308 was only 1.5 inches low at 300 and 3.5 low at 400. Under normal set up, the drop was more than double that.
I wish I understood the physics of it better, but What I do know is I have a .308 that is flatter to 400 yards than my 7 mag.
I have a .284 set up for 1000 yd that is flatter to 400 yds than my 6 X284 that is set up for 600 yd.

[JLA]

Originally Posted by Trevor1837

I'm looking for a mount for a marking xt-22 rifle, DNZ has a mount for the marlin 925 which is basicallyy the same rifle, will this work? Thanks for the help.

Im not 100% on that. maybe someone will come along that is familiar with the rifle you have.

But if the rifles are both based on the same action and D/T the same with the same spacing then it should work indiscriminantly for either rifle.

Best to email DNZ and explain the rifle you have and the rifle is similar to and let them tell you yay or nay.

Without the 2 rifles in front of me side by side i couldnt tell you one way or the other.

[Trevor1837]

Originally Posted by JLA

Im not 100% on that. maybe someone will come along that is familiar with the rifle you have.

But if the rifles are both based on the same action and D/T the same with the same spacing then it should work indiscriminantly for either rifle.

Best to email DNZ and explain the rifle you have and the rifle is similar to and let them tell you yay or nay.

Without the 2 rifles in front of me side by side i couldnt tell you one way or the other.

Well thanks for your help! I'll send them an email.

[JLA]

Originally Posted by reynolds357

I am well aware of putting cant into a scope to extend the range the scope can adjust to. You will also find that when you do this, with some scopes,the observed trajectory is flatter at lesser ranges. You are modifying where the line of sight of the scope and the bore intersect. When you compensate for it with the scope, at shorter yardages, you do not have to aim over nearly as much. It has to do with the physical effects of the angle of the erector. The downside is when you put extreme angle on many erectors you cause the scope to not adjust well and and hold zero. I discovered it by accident and then the engineer explained to me why it worked. I had set up a .308 for 1000yd.(big mistake) Instead of taking the $130 elevated base off I decided I would just see if my scope had enough adjustment to bring it down to a 200 yard zero. What I discovered was my .308 was only 1.5 inches low at 300 and 3.5 low at 400. Under normal set up, the drop was more than double that.
I wish I understood the physics of it better, but What I do know is I have a .308 that is flatter to 400 yards than my 7 mag.
I have a .284 set up for 1000 yd that is flatter to 400 yds than my 6 X284 that is set up for 600 yd.

I understand what your talking about. Its very difficult to wrap your head around.

[Trevor1837]

I would greatly appreciate it if anyone with experience with both the 925 and xt-22 would come along and help me out, thanks guys!

[JLA]

Based on what i can find comparing spec listings on the marlin website and watching comparisons on youtube they are the same rifles. The 925 is the old name for the new for 2011 XT-22 or so it seems.. Ill keep digging..

[Trevor1837]

Originally Posted by JLA

Based on what i can find comparing spec listings on the marlin website and watching comparisons on youtube they are the same rifles. The 925 is the old name for the new for 2011 XT-22 or so it seems.. Ill keep digging..

Thank you very much, I thought so but getting a second opinion is helpful before spending 60 bucks on something that might not work. Thanks!

[JLA]

Originally Posted by reynolds357

I am well aware of putting cant into a scope to extend the range the scope can adjust to. You will also find that when you do this, with some scopes,the observed trajectory is flatter at lesser ranges. You are modifying where the line of sight of the scope and the bore intersect. When you compensate for it with the scope, at shorter yardages, you do not have to aim over nearly as much. It has to do with the physical effects of the angle of the erector. The downside is when you put extreme angle on many erectors you cause the scope to not adjust well and and hold zero. I discovered it by accident and then the engineer explained to me why it worked. I had set up a .308 for 1000yd.(big mistake) Instead of taking the $130 elevated base off I decided I would just see if my scope had enough adjustment to bring it down to a 200 yard zero. What I discovered was my .308 was only 1.5 inches low at 300 and 3.5 low at 400. Under normal set up, the drop was more than double that.
I wish I understood the physics of it better, but What I do know is I have a .308 that is flatter to 400 yards than my 7 mag.
I have a .284 set up for 1000 yd that is flatter to 400 yds than my 6 X284 that is set up for 600 yd.

Been pondering on this for a day now. Physics is physics. Cant bend the rules and cant break em. A .308 cant shoot flatter than a 7mm mag unless is dangerously overloaded and pushing a bullet way faster than it normally does.

What your doing is imparting cant to your bases the scope rests on to skew the line of sight to the target your scope percieves, this requires you to adjust the erector to compensate for the angle and puts the adjustment in a different place.

It isnt hard to wrap your head around, it is relatively simple once you grasp the mathematic fundamentals, trying to understand what youre saying is very confusing. Trajectory requires an understanding of trigonometry and algebra. Knowing how to apply actual bullet velocities, weights, and ballistic co-efficients to equations to calculate minute of arc. The being able to switch your mental gearing from figuring the mathematics to applying them to the adjustment turrets of your optics.

Point here is.. The actual flight of the bullet is determined by angle, velocity, BC of the projectile, wind, and atmospheric conditions. It is a fixed path based on those variables and cannot be changed, dont care who you are, you can be Isaac Newton himself and you cannot change what happens to a bullet when its fired. It follows a trajectory until it falls to the ground or strikes a hard target. No amount of skewing the view of the scope or tweaking the adjustment knobs are gonna change how flat a given cartridge shoots. They simply shoot the way they shoot and the only way to change the trajectory is to change one of the variables listed above.

Just wanted to clear that up for those who are still pondering on it.

[reynolds357]

Originally Posted by JLA

Been pondering on this for a day now. Physics is physics. Cant bend the rules and cant break em. A .308 cant shoot flatter than a 7mm mag unless is dangerously overloaded and pushing a bullet way faster than it normally does.

What your doing is imparting cant to your bases the scope rests on to skew the line of sight to the target your scope percieves, this requires you to adjust the erector to compensate for the angle and puts the adjustment in a different place.

It isnt hard to wrap your head around, it is relatively simple once you grasp the mathematic fundamentals, trying to understand what youre saying is very confusing. Trajectory requires an understanding of trigonometry and algebra. Knowing how to apply actual bullet velocities, weights, and ballistic co-efficients to equations to calculate minute of arc. The being able to switch your mental gearing from figuring the mathematics to applying them to the adjustment turrets of your optics.

Point here is.. The actual flight of the bullet is determined by angle, velocity, BC of the projectile, wind, and atmospheric conditions. It is a fixed path based on those variables and cannot be changed, dont care who you are, you can be Isaac Newton himself and you cannot change what happens to a bullet when its fired. It follows a trajectory until it falls to the ground or strikes a hard target. No amount of skewing the view of the scope or tweaking the adjustment knobs are gonna change how flat a given cartridge shoots. They simply shoot the way they shoot and the only way to change the trajectory is to change one of the variables listed above.

Just wanted to clear that up for those who are still pondering on it.

While you are clearing it up, ponder on this a bit. A 180 gr .308 with .420bc and vel of 3000 fps is zeroed at 100 yds with a scope height of 1" above center of bore: Bullet path is -50 inches at 500 yds and you come up 10 minutes to compensate. If the scope is mounted at 4" above center bore, the path is -37.9 and you come up 7 minutes. Did Newton take the day off? No. Even though trajectory does not change, the way you compensate for that trajectory changes based on where the center plane of the scope and the bore intersect each other prior to the manipulation of that intersection by the erector.

[todd51]

Point here is.. The actual flight of the bullet is determined by angle, velocity, BC of the projectile, wind, and atmospheric conditions. It is a fixed path based on those variables and cannot be changed, dont care who you are, you can be Isaac Newton himself and you cannot change what happens to a bullet when its fired. It follows a trajectory until it falls to the ground or strikes a hard target. No amount of skewing the view of the scope or tweaking the adjustment knobs are gonna change how flat a given cartridge shoots. They simply shoot the way they shoot and the only way to change the trajectory is to change one of the variables listed above.

Just wanted to clear that up for those who are still pondering on it.

Whew, Josh sure glad you made that statement. I was "pondering" saying to myself, ain't no way changing scope cant is going to change the bullets trajectory, I mean flatten it. But I am a novice learner and follow your posts to learn. Thanks.

[JLA]

Your point is mine, just looked at from 2 different angles.

The trajectories are the same. no matter how you cut the mustard. Whether the scope is an inch off the bore or a foot, the trajectory the bullet follows is always the same.

And 180 gr .308 loaded to safe pressures in a longer than normal 26" barrel is only gonna do about 2700 fps. Im ralitvely sure youre just tossing numbers out there to make the math easy, but that would be an example of changing a variable (velocity) to get a flatter trajectory out of a certain cartridge.

And why would one mount a scope 4" above the bore to compensate for longer distances when a mount to get the scope that high would most certainly have to be custom machined, which would be cost ineffective to most shooters? Especially when a mounting system with a 20 or 25 MOA cant can be purchased for about 60 bucks that effectively and cost efficiently does exactly the same thing in that it changes the point at which the line of sight intersects with the trajectory of the bullet. AND keeps the scope around a comfortable 1.5 inches off the bore..

[JLA]

Originally Posted by todd51

Whew, Josh sure glad you made that statement. I was "pondering" saying to myself, ain't no way changing scope cant is going to change the bullets trajectory. But I am a novice learner and follow your posts to learn. Thanks.

youre very welcome todd. I just dont want any new shooters to fear trying an aspect of shooting that should be well within most shooters capabilites because they misunderstand the physics of it. I have spent a good part of my adult life educating myself in the mechanics of firearms and the physics of shooting. and I am more than happy to share my education with anyone willing to learn it. It was free to me and i will distribute it freely.

[reynolds357]

Originally Posted by todd51

Whew, Josh sure glad you made that statement. I was "pondering" saying to myself, ain't no way changing scope cant is going to change the bullets trajectory, I mean flatten it. But I am a novice learner and follow your posts to learn. Thanks.

I did not say it would change the trajectory. The flight path is the flight path. I said it would change the perceived trajectory, meaning how you compensate for the true trajectory with your sighting system.

[reynolds357]

Originally Posted by JLA

Your point is mine, just looked at from 2 different angles.

The trajectories are the same. no matter how you cut the mustard. Whether the scope is an inch off the bore or a foot, the trajectory the bullet follows is always the same.

And 180 gr .308 loaded to safe pressures in a longer than normal 26" barrel is only gonna do about 2700 fps. Im ralitvely sure youre just tossing numbers out there to make the math easy, but that would be an example of changing a variable (velocity) to get a flatter trajectory out of a certain cartridge.

And why would one mount a scope 4" above the bore to compensate for longer distances when a mount to get the scope that high would most certainly have to be custom machined, which would be cost ineffective to most shooters? Especially when a mounting system with a 20 or 25 MOA cant can be purchased for about 60 bucks that effectively and cost efficiently does exactly the same thing in that it changes the point at which the line of sight intersects with the trajectory of the bullet. AND keeps the scope around a comfortable 1.5 inches off the bore..

You would not want a 4" high mount. What you want is reap some of the benefits of a 4" mount by using cant. Trajectory is trajectory. Only speed, gravity, and resistance can change it. What we are trying to manipulate is perceived trajectory, or the way we compensate in sighting for trajectory.
You are still missing the point I am making. You can extend your point blank range by manipulating mount height. You can also extend it by simulating that same height manipulation by manipulating the bases at a certain cant.