Scope Mount Base 'Bedding' - Thoughts?

RoeStalker270

Well-Known Member
Hoping to pick some brains here of some people who have likely had more to do with this than myself..

So, I am currently in the process of changing all my scope mounts onto weaver/picatinny for the ability to interchange scopes, NV etc., my current job is replacing the scope bases on my Sauer 202. (two bases bolted to action for anybody unfamiliar) I notice some manuals/guides state that the bases should be 'bedded' to the action using epoxy or adhesive etc. In my mind, this seems messy, and likely to end up leaving marks on the action should these ever be removed again. I understand the idea that adding this layer of bedding should take up any imperfections in the two mating surfaces and increase stability and so on.

Anyway, I was happy enough to do this to be certain, so removed the mounts which were currently fitted to the rifle (Talley bases), these were fitted to the rifle from new, likely around 10 years ago, by the gunsmith when the rifle was purchased. No adhesive or bedding under the bases, no loctite on any of the screws, and as the screws had actually been put in the wrong places (different lengths), one of these was actually stripped and not doing very much of anything. (Luckily only the screw itself was damaged). Despite all of this, the rifle has always held a zero without any issue whatsoever, and shoots happily through the same hole at 100m. Just to add, this is on a .270.

My question being, is it really necessary to add anything more than a drop of loctite on the screws? If so, what would you use? and what sort of mess am I likely to be left with should I ever want to remove them?

Whilst I have maybe answered my own question here, maybe I have just been lucky, and if anybody has any experience with this, I'd love to hear about it.

Thanks.
 
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620 can form a pretty good bond that can take some shifting without heat. 431 is a lot easier to get apart. I use it a lot on bearings that have to be changed out fairly regularly. For a scope mount, it would be also feasible to use 243 for both the base and the threads.
 
I’ve Devcon bedded picatinny rails in the past but used a release agent so they are not bonded to the action. I don’t recall a base (bedded or not) ever coming loose in any of my set-ups.

If you do loctite the screws do not apply to the front screw that sits over the barrel tenon, just do the rears and clean up well.
 
I Devcon bedded/stuck a new picatinny rail onto my Bergara B13, its well documented the screws come loose even with loctite due to the fact the stock picatinny is poorly matched to the radius of the action and the screws are tiny, this happened to me when i first bought it so went the whole hog and i haven’t touched my scope settings since.
Regarding mess, just mask off around the base leaving a tiny gap all the way round and once everything is in place wipe up with a cotton bud and acetone, remove masking tape and repeat.
 
Depends. Older rifles that were built on patterns will have an element of variation from one to another, especially on external bits such as the bridges. This applies to older Mauser parker hale, rem 700 etc etc actions. A modern rifle built on CNC will have better tolerances.

Equally same applies to the scope mounts.

A smear of bedding compound will take up any gaps and avoid any future movement. Lapping the scope rings will also help.
 
Depends. Older rifles that were built on patterns will have an element of variation from one to another, especially on external bits such as the bridges. This applies to older Mauser parker hale, rem 700 etc etc actions. A modern rifle built on CNC will have better tolerances.

Equally same applies to the scope mounts.

A smear of bedding compound will take up any gaps and avoid any future movement. Lapping the scope rings will also help.
Indeed if you read the mounting instructions for Apel mounts they recommend a smear of epoxy.

With most epoxies if you use a layer of wax polish on top of the action it shouldn’t stick. Also most epoxies will also release at about 150 to 200°c so heat applied with a decent soldering iron will break them free.
 
**** idea IMO
Its the reason half the steel action 202s I see have bluing issues on the top of the action

If the bases need glue then get some different ones
or at worst make sure they are smooth and in full contact, you can run them over 800grit paper when its flush on the receiver to remove any high spots

I would loctite the base screws especially in aluminium actions, less torque more glue on the Ali ones.
They strip too easily
 
I’ve bedded picatinny rails and put them on without bedding, haven’t noticed a difference. Nothing has come loose. I don’t ever use loctite on any mounts or bases
 
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