tnshootist
New member
Wow. I guess I have been lucky. I have had lots of rifles through the years and never run into this.
Shimming a scope?
- Thread starter The Famous Grouse
- Start date
Ackman
New member
Originally Posted By: The Famous Grouse
Every time I think about this front or back question, I get a headache. Which is it? POI is too high. Shim under...
Handgun or rifle sights, or scope, move the rear sight/crosshairs in the direction you want point of impact to move. You want the bullet to hit lower, so lower the crosshair. In your case that can't be done, so you raise the front.
You don't want to max out the scope's adjustment. Best to have the crosshairs about in the center of their adjustment range, or a bit lower, when the gun is zeroed. Easy to do with Signature rings.
Every time I think about this front or back question, I get a headache. Which is it? POI is too high. Shim under...
Handgun or rifle sights, or scope, move the rear sight/crosshairs in the direction you want point of impact to move. You want the bullet to hit lower, so lower the crosshair. In your case that can't be done, so you raise the front.
You don't want to max out the scope's adjustment. Best to have the crosshairs about in the center of their adjustment range, or a bit lower, when the gun is zeroed. Easy to do with Signature rings.
Quote: You want the bullet to hit lower, so lower the crosshair. In your case that can't be done, so you raise the front.
I think you meant to say you lower the rear end of the scope, not the crosshair. Lowering rear end of scope (not possible) actually raises the crosshair.
Moving rear sight (ocular lens in case of a scope) in direction you want to move the POI or move the front sight (objective lens) in the opposite direction you wish to move the POI. (IOW, filing off the front sight would make bullet strike higher).
Regards,
hm
I think you meant to say you lower the rear end of the scope, not the crosshair. Lowering rear end of scope (not possible) actually raises the crosshair.
Moving rear sight (ocular lens in case of a scope) in direction you want to move the POI or move the front sight (objective lens) in the opposite direction you wish to move the POI. (IOW, filing off the front sight would make bullet strike higher).
Regards,
hm
Last edited:
Ackman
New member
Originally Posted By: hm1996 Quote: You want the bullet to hit lower, so lower the crosshair. In your case that can't be done, so you raise the front.
I think you meant to say you lower the rear end of the scope, not the crosshair. Lowering rear end of scope (not possible) actually raises the crosshair.
Moving rear sight (ocular lens in case of a scope) in direction you want to move the POI or move the front sight (objective lens) in the opposite direction you wish to move the POI. (IOW, filing off the front sight would make bullet strike higher).
Regards,
hm
You're making this more complicated than it needs to be. Yes the reticle isn't actually in the eyepiece, it's up around the adjustment saddle. But looking in the eyepiece you see crosshairs and they're a rear sight in relation to the muzzle. Moving them down has the same effect as moving a rear open sight down. Yes I said what I meant to say.......rear sight or crosshairs in direction you want bullet impact to move. That's all a person need remember. And in his case with the reticle already bottomed, the only way to make bullet impact lower still is to change the actual scope angle by raising the objective lens, or lowering the eyepiece. Either/both are done with signature ring inserts.
I think you meant to say you lower the rear end of the scope, not the crosshair. Lowering rear end of scope (not possible) actually raises the crosshair.
Moving rear sight (ocular lens in case of a scope) in direction you want to move the POI or move the front sight (objective lens) in the opposite direction you wish to move the POI. (IOW, filing off the front sight would make bullet strike higher).
Regards,
hm
You're making this more complicated than it needs to be. Yes the reticle isn't actually in the eyepiece, it's up around the adjustment saddle. But looking in the eyepiece you see crosshairs and they're a rear sight in relation to the muzzle. Moving them down has the same effect as moving a rear open sight down. Yes I said what I meant to say.......rear sight or crosshairs in direction you want bullet impact to move. That's all a person need remember. And in his case with the reticle already bottomed, the only way to make bullet impact lower still is to change the actual scope angle by raising the objective lens, or lowering the eyepiece. Either/both are done with signature ring inserts.
Originally Posted By: AckmanOriginally Posted By: hm1996 Quote: You want the bullet to hit lower, so lower the crosshair. In your case that can't be done, so you raise the front.
I think you meant to say you lower the rear end of the scope, not the crosshair. Lowering rear end of scope (not possible) actually raises the crosshair.
Moving rear sight (ocular lens in case of a scope) in direction you want to move the POI or move the front sight (objective lens) in the opposite direction you wish to move the POI. (IOW, filing off the front sight would make bullet strike higher).
Regards,
hm
You're making this more complicated than it needs to be. Yes the reticle isn't actually in the eyepiece, it's up around the adjustment saddle. But looking in the eyepiece you see crosshairs and they're a rear sight in relation to the muzzle. Moving them down has the same effect as moving a rear open sight down. Yes I said what I meant to say.......rear sight or crosshairs in direction you want bullet impact to move. That's all a person need remember. And in his case with the reticle already bottomed, the only way to make bullet impact lower still is to change the actual scope angle by raising the objective lens, or lowering the eyepiece. Either/both are done with signature ring inserts.
Quote:rear sight or crosshairs in direction you want bullet impact to move.
Not trying to pick nits, but OP stated he is confused as to direction he needs to move his scope. Maybe I'm misreading Quote:You want the bullet to hit lower, so lower raise the crosshair. ? We are totally in agreement that raising the front end of his scope will lower strike of bullet. Only difference of opinion is the direction in which the crosshairs move within the scope.
This is the part that I disagree with....if you raise the front end of scope, you are raising the CH, not lowering it. The reticle in a scope is same as the front sight so must be moved in opposite direction as you wish to move POI. To check this our, anchor a scope pointed at a target and, looking through the scope, turn elev. knob "DOWN" and you will see that the CH actually moves UP. Thus, when the CH is pointed at the target, barrel will be lower moving the bullet strike down on the next shot.
Regards,
hm
I think you meant to say you lower the rear end of the scope, not the crosshair. Lowering rear end of scope (not possible) actually raises the crosshair.
Moving rear sight (ocular lens in case of a scope) in direction you want to move the POI or move the front sight (objective lens) in the opposite direction you wish to move the POI. (IOW, filing off the front sight would make bullet strike higher).
Regards,
hm
You're making this more complicated than it needs to be. Yes the reticle isn't actually in the eyepiece, it's up around the adjustment saddle. But looking in the eyepiece you see crosshairs and they're a rear sight in relation to the muzzle. Moving them down has the same effect as moving a rear open sight down. Yes I said what I meant to say.......rear sight or crosshairs in direction you want bullet impact to move. That's all a person need remember. And in his case with the reticle already bottomed, the only way to make bullet impact lower still is to change the actual scope angle by raising the objective lens, or lowering the eyepiece. Either/both are done with signature ring inserts.
Quote:rear sight or crosshairs in direction you want bullet impact to move.
Not trying to pick nits, but OP stated he is confused as to direction he needs to move his scope. Maybe I'm misreading Quote:You want the bullet to hit lower, so lower raise the crosshair. ? We are totally in agreement that raising the front end of his scope will lower strike of bullet. Only difference of opinion is the direction in which the crosshairs move within the scope.
This is the part that I disagree with....if you raise the front end of scope, you are raising the CH, not lowering it. The reticle in a scope is same as the front sight so must be moved in opposite direction as you wish to move POI. To check this our, anchor a scope pointed at a target and, looking through the scope, turn elev. knob "DOWN" and you will see that the CH actually moves UP. Thus, when the CH is pointed at the target, barrel will be lower moving the bullet strike down on the next shot.
Regards,
hm
First of all, in all self centering reticle scopes the crosshairs or reticle does not move...there is a washer you are looking thru and that is what moves. Very few scopes are not made this way these days. I know there are some geniuses out there already typing away to "straighten" me out, all I can say is...if you don't believe me then take a scope apart and see for yourself.
My question to the OP is, did you mount this scope, bases and rings or did someone else do it??? Because if it wasn't you then there just might be a shim or shims under the rear base already. People do this a lot to get them more adjustment up, such as for long range shooting. You would be surprised at the number of people that come to me wanting a 20 MOA scope base and when I ask why they believe this will make their gun more accurate!!!
Second, I agree that it sounds like something is a miss with this thing but to say "never shim under a separate scope base" is not correct. Suppose the rear really is milled {or polished as suggested} too low??? Wouldn't that make it in misalignment now??? And wouldn't shims in the rear bring it into level???
My question to the OP is, did you mount this scope, bases and rings or did someone else do it??? Because if it wasn't you then there just might be a shim or shims under the rear base already. People do this a lot to get them more adjustment up, such as for long range shooting. You would be surprised at the number of people that come to me wanting a 20 MOA scope base and when I ask why they believe this will make their gun more accurate!!!
Second, I agree that it sounds like something is a miss with this thing but to say "never shim under a separate scope base" is not correct. Suppose the rear really is milled {or polished as suggested} too low??? Wouldn't that make it in misalignment now??? And wouldn't shims in the rear bring it into level???
Ackman
New member
Originally Posted By: msincFirst of all, in all self centering reticle scopes the crosshairs or reticle does not move...there is a washer you are looking thru and that is what moves. Very few scopes are not made this way these days. I know there are some geniuses out there already typing away to "straighten" me out, all I can say is...if you don't believe me then take a scope apart and see for yourself.
My question to the OP is, did you mount this scope, bases and rings or did someone else do it??? Because if it wasn't you then there just might be a shim or shims under the rear base already. People do this a lot to get them more adjustment up, such as for long range shooting. You would be surprised at the number of people that come to me wanting a 20 MOA scope base and when I ask why they believe this will make their gun more accurate!!!
Second, I agree that it sounds like something is a miss with this thing but to say "never shim under a separate scope base" is not correct. Suppose the rear really is milled {or polished as suggested} too low??? Wouldn't that make it in misalignment now??? And wouldn't shims in the rear bring it into level???
Sheesh...........whatever it is that "really" moves, the crosshairs change in relation to point of impact.
Second, never shim under a separate scope base........unless you can get it just right. How many people actually use a straightedge to check if front and rear bases are level with each other. Then if the rear of the action is low or high, how many can measure it accurately. And how many are gonna make the bases level and do it right? How many yokels just use a couple soda can thicknesses and call it good if the scope will zero?
My question to the OP is, did you mount this scope, bases and rings or did someone else do it??? Because if it wasn't you then there just might be a shim or shims under the rear base already. People do this a lot to get them more adjustment up, such as for long range shooting. You would be surprised at the number of people that come to me wanting a 20 MOA scope base and when I ask why they believe this will make their gun more accurate!!!
Second, I agree that it sounds like something is a miss with this thing but to say "never shim under a separate scope base" is not correct. Suppose the rear really is milled {or polished as suggested} too low??? Wouldn't that make it in misalignment now??? And wouldn't shims in the rear bring it into level???
Sheesh...........whatever it is that "really" moves, the crosshairs change in relation to point of impact.
Second, never shim under a separate scope base........unless you can get it just right. How many people actually use a straightedge to check if front and rear bases are level with each other. Then if the rear of the action is low or high, how many can measure it accurately. And how many are gonna make the bases level and do it right? How many yokels just use a couple soda can thicknesses and call it good if the scope will zero?
Originally Posted By: AckmanOriginally Posted By: msincFirst of all, in all self centering reticle scopes the crosshairs or reticle does not move...there is a washer you are looking thru and that is what moves. Very few scopes are not made this way these days. I know there are some geniuses out there already typing away to "straighten" me out, all I can say is...if you don't believe me then take a scope apart and see for yourself.
My question to the OP is, did you mount this scope, bases and rings or did someone else do it??? Because if it wasn't you then there just might be a shim or shims under the rear base already. People do this a lot to get them more adjustment up, such as for long range shooting. You would be surprised at the number of people that come to me wanting a 20 MOA scope base and when I ask why they believe this will make their gun more accurate!!!
Second, I agree that it sounds like something is a miss with this thing but to say "never shim under a separate scope base" is not correct. Suppose the rear really is milled {or polished as suggested} too low??? Wouldn't that make it in misalignment now??? And wouldn't shims in the rear bring it into level???
Sheesh...........whatever it is that "really" moves, the crosshairs change in relation to point of impact.
Second, never shim under a separate scope base........unless you can get it just right. How many people actually use a straightedge to check if front and rear bases are level with each other. Then if the rear of the action is low or high, how many can measure it accurately. And how many are gonna make the bases level and do it right? How many yokels just use a couple soda can thicknesses and call it good if the scope will zero?
I have been shimming separate scope bases for 30 some odd years, for various reasons, more elevation, optically centered scope, etc. ...never had an issue. In a perfect world, no you wouldn't want to, but will it kill the set up to put a .006" shim in the back???....well, it hasn't so far.
As to a straight edge....very very few rifles have the rear and front on the same plane. Just about all of them have a different height front and rear base. I will grant you that most people do not have the capability nor the knowledge to measure scope base level against bore centerline.
Actually, the cross hairs do not change in relation to POA...you aim for center and when the rest of the rifle is set and adjusted properly you still still put the cross hair/reticle on center. That stupid little washer causes you to move the rest of the rifle accordingly. All this is of course splitting hairs to the OP's cause.
My question to the OP is, did you mount this scope, bases and rings or did someone else do it??? Because if it wasn't you then there just might be a shim or shims under the rear base already. People do this a lot to get them more adjustment up, such as for long range shooting. You would be surprised at the number of people that come to me wanting a 20 MOA scope base and when I ask why they believe this will make their gun more accurate!!!
Second, I agree that it sounds like something is a miss with this thing but to say "never shim under a separate scope base" is not correct. Suppose the rear really is milled {or polished as suggested} too low??? Wouldn't that make it in misalignment now??? And wouldn't shims in the rear bring it into level???
Sheesh...........whatever it is that "really" moves, the crosshairs change in relation to point of impact.
Second, never shim under a separate scope base........unless you can get it just right. How many people actually use a straightedge to check if front and rear bases are level with each other. Then if the rear of the action is low or high, how many can measure it accurately. And how many are gonna make the bases level and do it right? How many yokels just use a couple soda can thicknesses and call it good if the scope will zero?
I have been shimming separate scope bases for 30 some odd years, for various reasons, more elevation, optically centered scope, etc. ...never had an issue. In a perfect world, no you wouldn't want to, but will it kill the set up to put a .006" shim in the back???....well, it hasn't so far.
As to a straight edge....very very few rifles have the rear and front on the same plane. Just about all of them have a different height front and rear base. I will grant you that most people do not have the capability nor the knowledge to measure scope base level against bore centerline.
Actually, the cross hairs do not change in relation to POA...you aim for center and when the rest of the rifle is set and adjusted properly you still still put the cross hair/reticle on center. That stupid little washer causes you to move the rest of the rifle accordingly. All this is of course splitting hairs to the OP's cause.
Ackman
New member
Originally Posted By: msincOriginally Posted By: AckmanOriginally Posted By: msincFirst of all, in all self centering reticle scopes the crosshairs or reticle does not move...there is a washer you are looking thru and that is what moves. Very few scopes are not made this way these days. I know there are some geniuses out there already typing away to "straighten" me out, all I can say is...if you don't believe me then take a scope apart and see for yourself.
My question to the OP is, did you mount this scope, bases and rings or did someone else do it??? Because if it wasn't you then there just might be a shim or shims under the rear base already. People do this a lot to get them more adjustment up, such as for long range shooting. You would be surprised at the number of people that come to me wanting a 20 MOA scope base and when I ask why they believe this will make their gun more accurate!!!
Second, I agree that it sounds like something is a miss with this thing but to say "never shim under a separate scope base" is not correct. Suppose the rear really is milled {or polished as suggested} too low??? Wouldn't that make it in misalignment now??? And wouldn't shims in the rear bring it into level???
Sheesh...........whatever it is that "really" moves, the crosshairs change in relation to point of impact.
Second, never shim under a separate scope base........unless you can get it just right. How many people actually use a straightedge to check if front and rear bases are level with each other. Then if the rear of the action is low or high, how many can measure it accurately. And how many are gonna make the bases level and do it right? How many yokels just use a couple soda can thicknesses and call it good if the scope will zero?
In a perfect world, no you wouldn't want to, but will it kill the set up to put a .006" shim in the back???....well, it hasn't so far.
*******It won't kill the setup if you do it right. If you know in fact that it's .006", and you have the shim stock for it. I've done the scope shim thing to get one on target, long before knowing what was really happening with that. And I've also certain rings out of necessity because there was no alternative......a pain in the butt getting it spot on. And I've shimmed bases too, nitpicky to get right, especially when dealing with the inconsistencies of uneven rings.
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As to a straight edge....very very few rifles have the rear and front on the same plane. Just about all of them have a different height front and rear base. I will grant you that most people do not have the capability nor the knowledge to measure scope base level against bore centerline.
****Yes, most of my Remingtons use an offset Burris insert. And even with level bases it doesn't mean conventional rings are on the same centerline. All the rings I've measured were off one from the other, and also to a lesser degree from front to back of the saddle. Many years ago I stopped using std. rings. Hope they're making them better now.
-----------
Actually, the cross hairs do not change in relation to POA...you aim for center and when the rest of the rifle is set and adjusted properly you still still put the cross hair/reticle on center. That stupid little washer causes you to move the rest of the rifle accordingly. All this is of course splitting hairs to the OP's cause.
Reticle changing in relation to POA? Of course not. POI is what I said.
My question to the OP is, did you mount this scope, bases and rings or did someone else do it??? Because if it wasn't you then there just might be a shim or shims under the rear base already. People do this a lot to get them more adjustment up, such as for long range shooting. You would be surprised at the number of people that come to me wanting a 20 MOA scope base and when I ask why they believe this will make their gun more accurate!!!
Second, I agree that it sounds like something is a miss with this thing but to say "never shim under a separate scope base" is not correct. Suppose the rear really is milled {or polished as suggested} too low??? Wouldn't that make it in misalignment now??? And wouldn't shims in the rear bring it into level???
Sheesh...........whatever it is that "really" moves, the crosshairs change in relation to point of impact.
Second, never shim under a separate scope base........unless you can get it just right. How many people actually use a straightedge to check if front and rear bases are level with each other. Then if the rear of the action is low or high, how many can measure it accurately. And how many are gonna make the bases level and do it right? How many yokels just use a couple soda can thicknesses and call it good if the scope will zero?
In a perfect world, no you wouldn't want to, but will it kill the set up to put a .006" shim in the back???....well, it hasn't so far.
*******It won't kill the setup if you do it right. If you know in fact that it's .006", and you have the shim stock for it. I've done the scope shim thing to get one on target, long before knowing what was really happening with that. And I've also certain rings out of necessity because there was no alternative......a pain in the butt getting it spot on. And I've shimmed bases too, nitpicky to get right, especially when dealing with the inconsistencies of uneven rings.
-----------
As to a straight edge....very very few rifles have the rear and front on the same plane. Just about all of them have a different height front and rear base. I will grant you that most people do not have the capability nor the knowledge to measure scope base level against bore centerline.
****Yes, most of my Remingtons use an offset Burris insert. And even with level bases it doesn't mean conventional rings are on the same centerline. All the rings I've measured were off one from the other, and also to a lesser degree from front to back of the saddle. Many years ago I stopped using std. rings. Hope they're making them better now.
-----------
Actually, the cross hairs do not change in relation to POA...you aim for center and when the rest of the rifle is set and adjusted properly you still still put the cross hair/reticle on center. That stupid little washer causes you to move the rest of the rifle accordingly. All this is of course splitting hairs to the OP's cause.
Reticle changing in relation to POA? Of course not. POI is what I said.
Originally Posted By: The Famous GrouseAppreciate all the feedback and yes it is a head scratcher as to what, exactly is the root cause.
I know the final fix is new rings, but to Shelton's point, I'd like to try to figure out what the cause is before trying to put out the fire by throwing money on it.
To complete the picture, the setup is a Weaver base with Weaver Quad Lock rings. So I can shim the base.
First thing I'm going to do is take Shelton's point and take everything apart and look for something that isn't right, put it all back together and see if somehow I messed up the setup. I'm pretty careful with the whole process, but then again I once put a carb back together and got everything right except that I forgot to include the float, so I full admit that sometimes the problem is me.
Assuming that doesn't fix the problem, I'm going to shim it just to verify that THAT fixes the problem. I may buy new rings after that, but I want to make sure I'm actually fixing the problem, because it could always be something else.
So to shim it, what I'm hearing guys say is to shim under weaver base, right?
And if that's the case, given the fact that my POI is currently high and I cannot adjust the scope any lower, I should therefore shim under... [insert your answer here]?
Every time I think about this front or back question, I get a headache. Which is it? POI is too high. Shim under...Thanks guys. Appreciate the advice.
Grouse
Hey Grouse, since the conversation has kinda veered off track, I wouldn't be surprised if you are not more confused now than when you first posted your question. I know I am, so let's take one thing at a time.
The shim goes under front end of scope base.
Signature rings are the perfect solution to such problems, but before Signature rings, gunsmiths have been shimming scope bases for decades.
Now that we have the hardware problem fixed, let's see what we can do for your headache, while passing on an excellent method to zero the rifle, once scope is properly aligned with the bore.
If a picture is worth a thousand words, how much is a video worth? Here is a very simple method which I have used for years to zero my rifles. It eliminates the need for grid marks on targets, counting clicks, etc. It also may help your headache.
Disclaimer: In the interest of full disclosure, I did not make this video; found it on the internet and fit in discussion perfectly.
Afraid we wandered off on several tangents about which way, or even if, crosshairs move to move the point of impact to coincide with the point of aim. The above video illustrates what is necessary to do that much better than words on paper.
Let us know when you get it sorted out.
Regards,
hm
I know the final fix is new rings, but to Shelton's point, I'd like to try to figure out what the cause is before trying to put out the fire by throwing money on it.
To complete the picture, the setup is a Weaver base with Weaver Quad Lock rings. So I can shim the base.
First thing I'm going to do is take Shelton's point and take everything apart and look for something that isn't right, put it all back together and see if somehow I messed up the setup. I'm pretty careful with the whole process, but then again I once put a carb back together and got everything right except that I forgot to include the float, so I full admit that sometimes the problem is me.
Assuming that doesn't fix the problem, I'm going to shim it just to verify that THAT fixes the problem. I may buy new rings after that, but I want to make sure I'm actually fixing the problem, because it could always be something else.
So to shim it, what I'm hearing guys say is to shim under weaver base, right?
And if that's the case, given the fact that my POI is currently high and I cannot adjust the scope any lower, I should therefore shim under... [insert your answer here]?
Every time I think about this front or back question, I get a headache. Which is it? POI is too high. Shim under...Thanks guys. Appreciate the advice.
Grouse
Hey Grouse, since the conversation has kinda veered off track, I wouldn't be surprised if you are not more confused now than when you first posted your question. I know I am, so let's take one thing at a time.
The shim goes under front end of scope base.
Signature rings are the perfect solution to such problems, but before Signature rings, gunsmiths have been shimming scope bases for decades.
Now that we have the hardware problem fixed, let's see what we can do for your headache, while passing on an excellent method to zero the rifle, once scope is properly aligned with the bore.
If a picture is worth a thousand words, how much is a video worth? Here is a very simple method which I have used for years to zero my rifles. It eliminates the need for grid marks on targets, counting clicks, etc. It also may help your headache.
Disclaimer: In the interest of full disclosure, I did not make this video; found it on the internet and fit in discussion perfectly.
Afraid we wandered off on several tangents about which way, or even if, crosshairs move to move the point of impact to coincide with the point of aim. The above video illustrates what is necessary to do that much better than words on paper.
Let us know when you get it sorted out.
Regards,
hm
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deaddogwalkin
Active member
Grouse, first thing I would try is take the scope off the gun and re-center the retical. Then re-mount the scope and see if that does not help. While it is off check to make sure that the mounts are right and the rings are OK. If that does not help then take the scope back off and re-center it but before you mount it give the scope dial scope the way you are running out of adjustment and see if that helps. I have only had to do that to one scope and It worked.
The Famous Grouse
New member
Originally Posted By: hm1996 Hey Grouse, since the conversation has kinda veered off track, I wouldn't be surprised if you are not more confused now than when you first posted your question. I know I am, so let's take one thing at a time.
The shim goes under front end of scope base.
Regards,
hm
Great! I was just shimming the left side of the scope and NOW you come in with this and I'm all confused again.
Appreciate the advice, really.
Step 1 is already complete, I've torn everything down. No obvious issues were found, but I put it back together. Everything appears to be straight. Base is not warped, rings are straight, everything is tight.
So now off to the range to shoot it and see where I stand. I have shims cut, so if it's hosed, I'll shim and go right back to the bench.
Many thanks.
Grouse
The shim goes under front end of scope base.
Regards,
hm
Great! I was just shimming the left side of the scope and NOW you come in with this and I'm all confused again.
Appreciate the advice, really.
Step 1 is already complete, I've torn everything down. No obvious issues were found, but I put it back together. Everything appears to be straight. Base is not warped, rings are straight, everything is tight.
So now off to the range to shoot it and see where I stand. I have shims cut, so if it's hosed, I'll shim and go right back to the bench.
Many thanks.
Grouse