Properly mounting a scope

[ajvigs]

Simply put, how does one properly mount a scope at home, and what does one need to do it right? I can pay to have it done, but doing it myself just seems better to me.

 

[DrMike]

Make certain the scope is level and straight. After a few efforts, most people can properly align a scope by sight. Look that it is not rotated one direction or another and that is is straight. Then, make certain the screws are tightened properly. Against, this will become a matter of feel. When beginning, many people benefit from a torque wrench that measures inch pounds (http://www.midwayusa.com/Product/71...m-accurizing-torque-torque-wrench-screwdriver). To assist in obtaining proper alignment, some people employ a scope alignment kit (e.g. http://www.midwayusa.com/Product/71...m-accurizing-torque-torque-wrench-screwdriver). These tools make what is an otherwise simple job foolproof.

 

[Guest]

I've been mounting my own scopes for years. My suggestion is, spend a little money and set yourself up to do it correctly, and you'll enjoy working on your own guns for many, many years. I'd get some semblance of the following tools:

• Gun cradle - this is useful for both scope mounting and cleaning, as well as other minor maintenance.
  1" Oak Dowel, 3-4' long and very straight - get this from Lowe's/Home Depot. It's useful for turning in rings and aligning them to the bore, generally.
  Alternately, a scope lapping and alignment kit (instead of the oak dowel) - you can get these in 1" and in 30mm, or in combination. I suggest getting the combo, as 30mm is the only reason to get this instead of the oak dowel, in my book.
  Small tube of grease with a very fine applicator tip - for greasing the leading edges of the dovetail when turning in rings.
  1000grit emory paper - for cleaning up the high spots on rings and lightly lapping them in. Also useful for breaking the edges of where the rings meet, to minimize scope ring marks.
  Inch-pound torque wrench - for properly tightening base and ring screws, as well as action screws.
  Gunsmith screwdriver set - do not use angle ground screwdrivers on guns. Get a real gunsmith set, and plan to spend some dollars on a decent set (but they will last a long time if you take good care of them). You don't have to have a $100 set, but you also want to avoid the $8 set from WalMart if you can. I like a set that comes with a single driver handle and many bits, as I can also use those bits in my inch-pound torque wrench.
  Blue loctite - don't get red or any other color. But especially not red, as it requires heat to "let go" where the blue does not.

Optionally, you could get an inexpensive laser bore sighter. I bought one on sale years ago ($19) and it's been a great tool. Other folks just remove the bolt and look down the bore to align the scope in a basic sense. Either way will work, and both still require sighting in at the range before hunting. You could also get a ring wrench from Leupold but it's not necessary. It's not expensive, though.

Mounting a scope is pretty easy. Just clean and degrease all the screws, then wipe down the action and the bottom of the bases with an oil rag. Not a slimy oil bath, just a light coating to keep water out and protect the metal. Put some blue loctite on the screws (a little goes a long, long way) and screw them in just hand tight. Get your torque wrench and follow the manufacturer's instructions on torquing them in place. Oh, and pay attention to put the right length screw in the right place. No screw threads hanging down into the bolt path inside the action (visually verify) and be sure the front screw doesn't bottom on the barrel threads but instead bottoms on the shoulder of the screw against the base. Use a short screw in the front hole, is the basic deal there, as long as it gets into the threads a few turns.

Once you have the bases on, it's pretty easy to put the rings on. Loctite the cross screws in weaver style rings and torque the lower half in place. Lay the dowel rod in the rings and check for gaps around the ring surface area that will contact the scope. (Obviously this won't work if you're mounting a 30mm scope, so you'd want to invest in a scope lapping setup for that. If you have high spots on the rings (many do) get the 1000gr paper, wrap it around the dowel, and then screw the ring caps on loosely. Be sure you're in both rings and evenly screwed in, with the emery paper in the actual rings. Gently, very gently, lap the rings with the emery paper, just a stroke or three, then tighten the screws, and stroke them again. I usually stroke/tighten about three or four times, depending on the gaps I observe. Remember that you can always take more material off, but putting it back is tough. Don't sand the rings until they don't hold the scope tube. Once you get the rings lapped a little, pull the caps off, keeping the front and rear "matched" to their lowers, both in terms of which one, and which "side" of the cap is the front. Gently break the edges of the rings where they touch the scope tube on the inside of where the ring halves meet. Wipe everything down with a shotgun patch with some Hoppe's on it, or a blue shop towel with some oil, just to get residue off. Then lay the scope in and mount the ring caps with the torque wrench. I use blue loctite on the ring screws, but many folks don't. Never had a problem, so not about to stop now. I did have a ring cap or two loosen prior to using the blue loctite, which is why I use it. Others have not had a problem going "dry" with their ring screws. Do not oil any screws.

For rotary dovetail rings, it's a little more complicated. You mount the front ring to the dowel (or follow the instructions on the Leupold ring wrench) and grease the dovetail before you turn it into place. Try to get the front lined up with the bore. This is where the long dowel helps, as you can center it over the bore and be in good shape. Once you get that in place, pop the ring cap, get the rear ring bottom in place on the base, and screw the caps back on, over the dowel (now acting as an alignment guide for the rear ring). Tighten the windage screws (blue loctite!) with, you guessed it, the torque wrench. Then go through the lapping check and break the inner edges where the ring halves meet. Mount the scope in the rings, being careful to get the crosshairs level, and you're nearly done.

After you get the scope in place, use whichever method you want for boresighting, and get it set up for testing at the range. When you go to the range, I suggest you start at 25yds, shoot one, and adjust. Remember that adjustments will move a much smaller distance at 25yds than at 100, so your .25moa adjustments at 100 will only move you 1/16th of an inch at 25yds. Once you get centered and properly elevated at 25, you should be within close proximity to the bullseye at 100, and you can adjust from there.

Working on your own rifles is very rewarding. Just be aware that your friends will find out you do your own work, and start bringing their guns to you for scope mounting and such. It's a slippery slope...

 

[meatmachineman]

Dub's got you pretty well set. About the only thing I do different is the lapping. A family friend with a machine shop in his garage made me a 1" lapping bar a few years back. I typically utilize valve grinding compound (available cheaply at most auto parts stores) in place of the 1k grit emery paper. For most rings I'll run the bar and compound until I've taken all the surface finish off the inside of the rings. That does change depending on the ring and the fit to the scope prior to starting.... sometimes you just don't have as much ring material to take off before the ring doesn't hold the scope. As Dub said, it easy to remove material but much harder to add. Once I have the rings lapped to my satisfaction, I'll remove as much of the compound as I possibly can using clean clothes. You don't want any of the compound grit left in the ring.

 

[tddeangelo]

Dub's got you pretty well set. About the only thing I do different is the lapping. A family friend with a machine shop in his garage made me a 1" lapping bar a few years back. I typically utilize valve grinding compound (available cheaply at most auto parts stores) in place of the 1k grit emery paper. For most rings I'll run the bar and compound until I've taken all the surface finish off the inside of the rings. That does change depending on the ring and the fit to the scope prior to starting.... sometimes you just don't have as much ring material to take off before the ring doesn't hold the scope. As Dub said, it easy to remove material but much harder to add. Once I have the rings lapped to my satisfaction, I'll remove as much of the compound as I possibly can using clean clothes. You don't want any of the compound grit left in the ring.

All that to mount your NCStar scopes??????

:roll:

:grin:

 

[Guest]

:lol: :lol: :lol: :lol: :lol: :lol:

And I have to say, the grammar nazi in me is wondering if there's any disadvantage to wiping the rings down with dirty clothes instead of getting clean clothes out of the dresser...

(I know, total smart azz stuff there...but it's a failing for me.)

 

[Thankful Otter]

dubyam

good post and great information, ( ignore Tom ) I printed it out and will use it, when someone ask me about mounting a scope I will hand them a copy of your post. Well done sir.

I also liked your second post, but for a different reason. Being a smart azz, in training, it was perfect

 

[meatmachineman]

Dub's got you pretty well set. About the only thing I do different is the lapping. A family friend with a machine shop in his garage made me a 1" lapping bar a few years back. I typically utilize valve grinding compound (available cheaply at most auto parts stores) in place of the 1k grit emery paper. For most rings I'll run the bar and compound until I've taken all the surface finish off the inside of the rings. That does change depending on the ring and the fit to the scope prior to starting.... sometimes you just don't have as much ring material to take off before the ring doesn't hold the scope. As Dub said, it easy to remove material but much harder to add. Once I have the rings lapped to my satisfaction, I'll remove as much of the compound as I possibly can using clean clothes. You don't want any of the compound grit left in the ring.

All that to mount your NCStar scopes??????

:roll:

:grin:

Of course.... you don't want to screw up those high end optics! Replacing scopes with the latest in plastic lens technology isn't cheap! :grin:

 

[meatmachineman]

:lol: :lol: :lol: :lol: :lol: :lol:

And I have to say, the grammar nazi in me is wondering if there's any disadvantage to wiping the rings down with dirty clothes instead of getting clean clothes out of the dresser...

(I know, total smart azz stuff there...but it's a failing for me.)

I'd expect nothing less! Main point was it tends to take me several pieces of cloth or patch to get all the compound out... kinda until it pass the white glove test.... but you may have already surmised as much! :wink:

 

[Mud]

This is the best video I have found so far.

https://www.youtube.com/watch?v=COoXVpG ... ata_player

Larry