Bedding a Scope Base

[636]

I'm slowly yet surely building up my rifle and after doing some research it looks like there's a good chance that my scope base will need to be bedded.

I've got a couple of questions about the process:

Is this something that a typical gunsmith would be able to do? I'm a little nervous about dumping epoxies anywhere near my action so I'd rather have it done by someone who knows what they're doing.

Currently the rifle is completely stock, would there be any changes to the mounting point for the scope base if I were to have work done to the rifle down the road?

Rifle is a Remington 700 SPS-V and I'm working with a Badger Ordinance 20moa 1 piece base.

Thanks for any help you can provide!

[CSACANNONEER]

I've bedded actions but, I've never heard of bedding a scope base. Please enlighten me about it. What exactly is the problem and how does one bed a scope base. For once, I'm not being sarcastic. I'm really curious.

[ocabj]

Bedding a scope base can be done using bedding material used for actions/stocks. The concept of bedding the base is to fill in any gap between the scope base surface and the surface of the receiver. A few people do this.

The surfaces of the bottom of a scope base and the top of a receiver aren't going to be perfect. There may be slight surface irregularities that aren't visible/noticable to the human eye. Maybe the top of the receiver between the scope base holes has a minute concave surface from hole to hole (front to back). Thus, putting bedding material will allow the surfaces to be filled. The amount of bedding that eventually gets trapped between the base and receiver after tightening things down will probably be a very minute film, and most likely only in a few small sections.

Getting this positive full surface contact between the base and receiver will insure minimal flexing of the scope base.

That said, I've never bedded a scope base before.

[CSACANNONEER]

ocabj,

Thanks. Now I can say that I learned something today!

[Rust]

You can also bed rings rather than lap them. Just remember if you're bedding anything to fill all the holes and recessed areas with clay or wax before you start to epoxy because if you get flow into a pin or screw hole or into a groove in the receiver its going to be stuck in there permanently. And use some sort of release agent on anything you want to get back again.

[ocabj]

Lapping rings is meant to improve the alignment of rings. If there is a any misalignment of rings, no matter how slight, bedding the inside surfaces isn't going to help anything. You're still going to have pressure exerting against the tube from opposite directions putting flex on the scope tube. At least, that's how I see it.

[MAX100]

Farrel Ind. recommends that their scope bases should be bedded. They have a channel cut in the bottom for bedding compound. It is the only way to get a true custom scope base to receiver fit.


GC

[636]

Given the responses, I'm starting to think that spending the money elsewhere may be a better plan.

Next time I'm in my local shop I'll see what they say just for curiosity sake.

[Rust]

When bedding rings you don't tighten the rings up. Put a thin layer of bedding compound around the inside of the rings, release agent on the scope, and lightly press the scope into the rings. If you tighten them they'll warp it, but with light pressure the compound will fill the points where the rings are not touching. When the it gets to the point where its pretty firm trim any excess off, and if you like throw a little rosin or lapping powder (not compound, just the grit) into the rings so they'll grip tighter. Remember to fill any holes with clay so that you don't lock anything together or cover up any screws you might want to get to later.

[FatOnCoke]

Given the responses, I'm starting to think that spending the money elsewhere may be a better plan.

Next time I'm in my local shop I'll see what they say just for curiosity sake.

I agree with you there! Sounds like a job for the extremely dedicated lacking social skills.

[Black_Talon]

Why not just use the Burris Signature rings?

[rksimple]

When bedding rings you don't tighten the rings up. Put a thin layer of bedding compound around the inside of the rings, release agent on the scope, and lightly press the scope into the rings. If you tighten them they'll warp it, but with light pressure the compound will fill the points where the rings are not touching. When the it gets to the point where its pretty firm trim any excess off, and if you like throw a little rosin or lapping powder (not compound, just the grit) into the rings so they'll grip tighter. Remember to fill any holes with clay so that you don't lock anything together or cover up any screws you might want to get to later.

This fixes the symptoms, but not the cause of the problem. The cause is an ill-fitting base. When torqued against the receiver bridge, even the most robust of bases will bend a bit. This then throws the rings out of alignment as the top of the rail is tweaked. Bedding the base helps to remedy the root cause of the problem.

[Rust]

Thats totally true, I'm not saying bedding the rings is better, but it is an option he could consider. Especially since he was wondering about bedding causing problems in the future should he want to send the action in to get worked on. Would be the same as a permanent version of Burris's signature rings like black talon mentioned. They work great, I use a pair on my savage. If you bed the bases you still have to use a light hand so that you don't torque them as you bed them, and have to check to ensure the holes are even aligned in the receiver. And even if you do it right you have part of the pressure bearing on epoxy rather than metal. Thats why most people lock the bases down and just lap the rings in the end, since that leaves everything with metal to metal fit all the way around. In the past I've gone so far as to stone the bases to sit flat with a parallel bar. Then fit the rings.
edit-I hope I'm not coming off as being argumentative, just trying to point out some other options.

[rksimple]

Thats totally true, I'm not saying bedding the rings is better, but it is an option he could consider. Especially since he was wondering about bedding causing problems in the future should he want to send the action in to get worked on. Would be the same as a permanent version of Burris's signature rings like black talon mentioned. They work great, I use a pair on my savage. If you bed the bases you still have to use a light hand so that you don't torque them as you bed them, and have to check to ensure the holes are even aligned in the receiver. And even if you do it right you have part of the pressure bearing on epoxy rather than metal. Thats why most people lock the bases down and just lap the rings in the end, since that leaves everything with metal to metal fit all the way around. In the past I've gone so far as to stone the bases to sit flat with a parallel bar. Then fit the rings.
edit-I hope I'm not coming off as being argumentative, just trying to point out some other options.

I understand completely. And you don't sound argumentative.

The problem with all the fixes mentioned (and I have some Burris Zee rings as well) is that it just gets around the fundamental problem. It may not matter depending on what you plan to do with the scope/rifle. If the rings and/or scope are not aligned with the axis of the bore, adjustment is needed, be it through the offset inserts or by lapping. Lapping or bedding the rings wont bring the scope back to the axis of the bore, just eliminate the torquing on the scope tube. Internal adjustments of the scope are used instead and this can be problematic, especially if the scope will be used along its entire range of travel. The Burris rings are great for this because no internal adjustment really needs to be done. The rings do, however, lack in the robustness department when compared to seekins, badger, or the like.

ETA: The above also assumes the holes are drilled correctly on the receiver. Without that, well, there are other issues.