Pillar block bedding a chassis questions

[wywindsor]

Has anyone done this with success? I see Wolf has vid on bedding, but not with pillars.

I have a cnc shop that will build me a custom chassis for a Bat M action. This is a single shot magnum. Do you have recommendations on how much clearance one uses for bedding?

 

[WSnyder]

.050" is a typical bedding thickness on a traditional stock. Most people skim bed a chassis so in that case .000" allowance for a chassis.

 

[Carl S]

Chassis or stocks with bedding blocks.I prefer to do a full bedding job.skim bedding will probably work fine.but a full bedding job is better.ymmv.

 

[wywindsor]

What is the best material for bedding in aluminum? I was thinking Belzona.
Also should I machine slots, stair steps or small holes for the epoxy to adhere to?

 

[wywindsor]

This is the print.

 

[Sniperhandle]

What is the best material for bedding in aluminum? I was thinking Belzona.
Also should I machine slots, stair steps or small holes for the epoxy to adhere to?

Belzona is an awesome epoxy product, When I worked for Caterpillar we used it to repair blocks that had electrolosis damage where the liner O-rings seat.

 

[wywindsor]

We use it at the refinery I work at in pump cases. I thought if it will endure what we put it through it would out live the gun.

 

[Fast14riot]

We use it at the refinery I work at in pump cases. I thought if it will endure what we put it through it would out live the gun.

When it comes to bedding rifles for accuracy, the first and foremost consideration is shrinkage during and post cure. Next is compressive strength. I don't care how strong, sticky, machinable any epoxy is if it shrinks and then I have a sloppy action fit. Look up the minimum film thickness for your chosen bedding compound. Likely in the area of .005-.010", could be more. Thats your absolute minimum. 2x that is a better minimum safe clearance.

 

[ELR LVR]

What is the best material for bedding in aluminum? I was thinking Belzona.
Also should I machine slots, stair steps or small holes for the epoxy to adhere to?

Never heard of it
So watched a video of it, Amazing!

Apparently, it will bond through even to an oily surface or water wet surface
So now my question is,
what the heck do you use for a release agent then for that stuff?
Looks kind of expensive to use for bedding
---
I am reading guys use it for the inside of cylinder bores?
is this inside the actual bore where the cylinder rings pass by it?
(--- for that we usually weld in then rebore the cylinder )
or the epoxy is used inside the water cooled cylinder jacket (not in the bore itself)

 

[Fuj]

For what it's worth.....I do not bed chassis builds that has a primary
v-block design. I just take a tube wrapped in crocus and rub the V
area to knock off any edge burrs. I will put a light dab of Marine Tex
on the lug, That's it.....

 

[BuffaloBill]

For what it's worth.....I do not bed chassis builds that has a primary
v-block design. I just take a tube wrapped in crocus and rub the V
area to knock off any edge burrs. I will put a light dab of Marine Tex
on the lug, That's it.....

I was wondering about this topic. I read on “what the pro’s use” regarding whether to bed a chassis or not. About half the people say they don’t. Which surprised me.

I’ve only done four rifles in chassis. Two were Bravos using Tikka actions. Two were MTD ACC, one the original and one the Elite, using a Kauger and a Borden. In all four cases, I used the dial indicator in the below pic to check for movement while each action screw was backed off from a torqued condition. All of them showed (what I consider) massive movement under this test. Like tens of thousandths, 40-60. After careful bedding with Marine Tex the measured movement is a thousandths or less.

Three of these rifles have shot groups in the zeros. The fourth one may also be capable of this, but the owner hasn’t given it any range time to find out.

Has this been found to be less important than previously thought?

 

[DR_2297]

For V blocks I don’t bed them. A strip of packaging tape on the V contact surfaces will take up any and all variation.

 

[tobnpr]

Looks kind of expensive to use for bedding

One thing if ya have it laying around from a specific application where it was needed.
It won't do a damn thing any better than Marine-Tex or Devcon putty when it comes to bedding an action, and the short working time is a negative IMO.

But hey, whatever floats yer boat.

 

[Sniperhandle]

In my way of looking at it, Pillar Bedding a Chassis with an aluminum V-block or block is not necessary as the whole reason for Pillar bedding is to limit the compression of Wood, Fiberglass, Plastic etc. Most Pillars are made from Alum. So it is not necessary. Skim bedding would be all that is needed.

 

[wywindsor]

For those that used Belzona, What did you use for a release agent. After watching the vid it scares me that I would never get the action out.

 

[ELR LVR]

One thing if ya have it laying around from a specific application where it was needed.
It won't do a damn thing any better than Marine-Tex or Devcon putty when it comes to bedding an action, and the short working time is a negative IMO.

But hey, whatever floats yer boat.

I've bedded with JB weld with fine results from it
Compression strength is good etc etc
This is a stock Ruger American rebarreled and a Magpul Hunter stock bedded with JB Weld
it does this pretty consistent;y with different guys shooting it at 600 yds, even newbies
And with the crappy magpull bipod vs a Harris
Price wise, I guess if you have the expensive stuff laying around sure use it up
But even $20 JB weld works so good I've seen top gunsmiths use it

 

[tobnpr]

I've bedded with JB weld with fine results from it
Compression strength is good etc etc
This is a stock Ruger American rebarreled and a Magpul Hunter stock bedded with JB Weld
it does this pretty consistent;y with different guys shooting it at 600 yds, even newbies
And with the crappy magpull bipod vs a Harris
Price wise, I guess if you have the expensive stuff laying around sure use it up
But even $20 JB weld works so good I've seen top gunsmiths use it

Absolutely- didn't mean to slight JB...I'm doing a .284 with it this week

 

[Lefty2506]

I've bedded with JB weld with fine results from it
Compression strength is good etc etc
This is a stock Ruger American rebarreled and a Magpul Hunter stock bedded with JB Weld
it does this pretty consistent;y with different guys shooting it at 600 yds, even newbies
And with the crappy magpull bipod vs a Harris
Price wise, I guess if you have the expensive stuff laying around sure use it up
But even $20 JB weld works so good I've seen top gunsmiths use it

I use the Devcon plastic steel because it has higher compressive strength than JB Weld, at essentially the same price, and because (like JB Weld) I can get it at Walmart. I also like the little twin tube dispenser so that I don't have to really measure anything out.

I did my first few bedding jobs (late '90s) with Devcon F2, but that stuff doesn't age well sitting on the shelf and you can't really buy it in small quantities. All the data I could find indicated that the Plastic Steel had all the same properties as F2. I've done 3 rifles with it now, and its been super easy.

As far as chassis go, I'm not sure we're talking about the same thing if you're actually trying to put pillars in one. My understanding is that a pillar is normally a tubular insert that gets glued into the stock at the action screws. Their purpose is to replace the compressible wood/composite that the action screws would otherwise torque down against. On a Chassis, this area is already made out of aluminum so there's no point in installing a pillar. Now, if you took a chassis and opened up the inlet to make more room for the epoxy, and LEFT the area around the action screws like they were pillars, that would make sense. Probably more work than its worth compared to just doing a skim coat, but I don't have enough experience to make that call.