How to bed a rifle.

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I try to avoid glass bedding. Machined aluminum block is IMO a far superior and more long term durable solution. Glass bedding degrades and weakens with shooting. When I do "glass bed" a rifle, I do it with original formula J.B. Weld and use Turtle wax hardshell wax for the release agent.
 
I've mostly done Mausers...flar bottom receivers.They have bosses around the gurs screws.

I begin by turning up guard screw ferrules large enough to make a counterbore for that boss on both ferrules.

I tune the length to be correct for the receiver. so I get a small amount,mayb ,010,clearance with the mag box.

The stock before bedding must be inletted to accept the receiver at the proper heights and barrel channel alignment.

Leaving that intact,I open the stock guard screw holes up to accept the ferrules with epoxy clearance and room for the ferrules to find their own unstressed location.

Then I epoxy in the pillars.

Now that I have pillars to give me repeatable X.Y,and Z location, I can remove stock material to "free float" material away,every place but the pillars.

Now if I place the barreled receiver in the stock,it is located in the stock,strain free,suspended only on the pillars ,with an air gap eveywhee else.

If I want .100 clearance around the barrel channel,I can mill it out.

I use multiple layers of thick vinyl tape on the barrel.

Fill all undercuts,pockets,anything that would lock the gun in.Do a mock up assembly to make sure everything goes.

I use AccraGlass Gel because it does not run and leak.

I can apply the resin,snug up the screws,,and everything is relaxed and free to mold to the space.

When I torque my guard screws, I'm not going to crush the steel pillars.

Note two things if you are dealing with a rifle that has recoil.

Stock crossbolts prevent the slabs of stock surrounding the mag box from bowing out under recoil. Its the bowing out that splits the stock through the wood behind the recoil lug.

In addition,the mag box is part of the structure that transmits recoil energy.

The front face of the magbox should support the stock material behind the recoil lug.

Thee are spots at the rear of the mag box that will transfer recoil near the trigger mortice,and,unlike the upper tang,the lower tang has well supported wood behind it. The lower tang can transmit some recoil.

Not so with the upper tang.

And do not use the trigger guard to pull the bottom metal out of the glass.
 
[QUOTEI try to avoid glass bedding. Machined aluminum block is IMO a far superior and more long term durable solution. Glass bedding degrades and weakens with shooting. When I do "glass bed" a rifle, I do it with original formula J.B. Weld and use Turtle wax hardshell wax for the release agent. ][/QUOTE]

Epoxies are ,or can be,engineered for a particular purpose. I'm not commenting on JB Weld. Maybe its accidentally great for bedding.

If,in my experience,my chosen bedding compound was failing me,I might question my choice.

I'm sure Brownells consulted /collaborated with the epoxy manufacturer to select an epoxy appropriate to the task.

Dexcon s a specialist in filled epoxies. I'm not too bashful to call a tech dept and ask questions.

One characteristic to be aware of is the "stacking" of the filler to become interference.

Aluminum bedding blocks can work,but beware.

There is a reason Nesika Bay wire EDM's their receivers out of pre-hard steel.

All receivers warp in heat treat. They are not re-machined.

The CNC machined bedding block will not perfectly fit a warped receiver.

The pillar and Vee block technique for a round receiver begind with surface grinding two flats on the receiver to mate to the vee-block.

I used a Hermann Schmidt vise and precision angle plate to regrind a Husky receiver floor, lug,rails,and receiver face flat and square. That gave the Lilja barrel a chance to shoot. It does pretty well.

In order for an aluminum bedding block to fit,you need to know how to use Dykem Hi-Spot and a scraper. With absolutely minimum torque on the screws,if you get 90 % blue transfer from the receiver to the bedding block,you have something.
I'm not bad mouthing bedding blocks.
I'm cautioning against unverified assumptions about fits.

You cannot assume a heat treated steel receiver remains straight,square,flat and true.

If your guard screws turn 1/4 or 1/3 turn coming up to torque,what does that tell you? Food for thought.
 
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HiBC said:
[QUOTEI try to avoid glass bedding. Machined aluminum block is IMO a far superior and more long term durable solution. Glass bedding degrades and weakens with shooting. When I do "glass bed" a rifle, I do it with original formula J.B. Weld and use Turtle wax hardshell wax for the release agent. ]
Click to expand...

Epoxies are ,or can be,engineered for a particular purpose. I'm not commenting on JB Weld. Maybe its accidentally great for bedding.

If,in my experience,my chosen bedding compound was failing me,I might question my choice.

I'm sure Brownells consulted /collaborated with the epoxy manufacturer to select an epoxy appropriate to the task.

Dexcon s a specialist in filled epoxies. I'm not too bashful to call a tech dept and ask questions.

One characteristic to be aware of is the "stacking" of the filler to become interference.

Aluminum bedding blocks can work,but beware.

There is a reason Nesika Bay wire EDM's their receivers out of pre-hard steel.

All receivers warp in heat treat. They are not re-machined.

The CNC machined bedding block will not perfectly fit a warped receiver.

The pillar and Vee block technique for a round receiver begind with surface grinding two flats on the receiver to mate to the vee-block.

I used a Hermann Schmidt vise and precision angle plate to regrind a Husky receiver floor, lug,rails,and receiver face flat and square. That gave the Lilja barrel a chance to shoot. It does pretty well.

In order for an aluminum bedding block to fit,you need to know how to use Dykem Hi-Spot and a scraper. With absolutely minimum torque on the screws,if you get 90 % blue transfer from the receiver to the bedding block,you have something.
I'm not bad mouthing bedding blocks.
I'm cautioning against unverified assumptions about fits.

You cannot assume a heat treated steel receiver remains straight,square,flat and true.

If your guard screws turn 1/4 or 1/3 turn coming up to torque,what does that tell you? Food for thought.[/QUOTE]
But, its guaranteed a glass bedding job will break down with use.
 
[QUOTEBut, its guaranteed a glass bedding job will break down with use. ][/QUOTE]

I have not found that to be true ,and I still have a bedding job I did over 20 years ago. The magnums have held up welll,too. I did find Micro-Bed disappointing.

Once again,without saying anything good or bad about JB Weld,I have not used it for bedding compound.

You have,and apparently it has failed you.

My Hi=Tec Specialties and Garrett AccraLite stocks are quality,light weight foam core glass.kevlar and epoxy stocks. I bedded them. The epoxy composite in the original stocks has not failes,and neither has the epoxy composite in the bedding.

How are bedding blocks set into a composite stock? My Win M-70 Laredo came with an HS Precision stock which kas a bedding block.

The bedding compound HS Precision used to set in the aluminum bedding block when the stock was made has not broken down. They just don't use release agent on the bedding block.

I don't know if it makes any difference,but they don't use JB Weld .

Another issue might be Tupperware stocks.,or,the substrate the stock is composed of.

A characteristic of plastics like polyethylene and polypropylene s that glues like epoxy just don't stick very well.

Without adhesion,the shell of bedding compound will break down
 
I don't believe every barreled action and every aluminum bedding block are made to fit perfectly. Some may be awfully close and not benefit from bedding while other's could use the bedding. If manufacturer's can't get every stock, wood or otherwise perfect for the barreled action going into it, how do they manage to do so with bedding blocks?
 
I have used commercial bedding compound, clear epoxy and J.B. Weld. My favorite and go to anymore is J.B.Weld. But I don't recall ever having any bedding compound break down on me. Accua Glass I tried many years ago, never figured out how anyone could use that runny stuff. Then it came out in gel and that had to be better but I was already into J.B. Weld by then and I'm not changing.

I am not convinced pillars by themselves are all that great. But if you pillar bedded and then glass bedded the action surface around the pillar, my guess is it would be super! The pillar would ensure the wood under it all never compressed and the glass would support the whole area around the pillar. Unfortunately for me I've never figured out how to do the pillar system. Keep wanting to try and make some with copper tubing but never convinced myself I can do it alright. Need an old seldom used inexpensive gun to try it on. Have though a lot about trying it on my Mossberg Patriot. Thinking the pillar and J.B. Weld would support that plastic trigger guard.
 
I used the Devco steel from Brownells , it's pricey but it worked well . I bedded my Remaining 700 in the HS Precision aluminum block stock , would always see rub marks and I wanted a Rock solid base . I watched videos , read up on and decided to give it a try . Just be careful not to go above the half way point on the circumference or it's not comming out , it's bedded for life . Do all the homework and it will work out fine . The hard part is waiting , will it release from the stock ? We always want to improve things . I also bedded my CZ 452 Varmint 22 lr. With that barrel screw , also worked well . Hey , if it doesn't , another excuse to buy a new toy . Go for it .

Chris
 
Marine Tex is one of the best bedding agents I have ever used and all that was used when I was working professionally. If you rub release agent (Johnson's Paste Wax) into the metal with a polishing cloth, the bedding comes out smooth and shiny like glass. I have also known some to do great things with Devcon.

Most modern rifles are bedded tang to recoil lug. Commonly, the action screw holes are drilled out and aluminum pillars embedded as well. The chamber area of a barrel may be done. I can see the argument for bedding the entire length from receiver to the end of the barrel channel but I can also see bedding the barrel being really problematic if everything is not perfect and even, as the stresses will try to go somewhere and a free-floated barrel gives an avenue for energy to travel and then return to a consistent static state.

Aluminum chassis and bedding blocks are great but as pointed out above, won't have perfect content. Many are cut on a CNC machine and will have a series of steps left from milling cutters. If you torque a receiver down to this, you're torquing a steel contact surface onto many very thin high points on a softer metal (aluminum). Will the torque and the stress from firing cause the hardened steel to wear on these high points and cause a gradual shift? I can't say for sure one way or the other but I know that I have done skim bedding jobs on aluminum chassis to fill in the spots between the high points. I can tell you the rifles shot phenomenal but I can't say they wouldn't have done exactly the same if they had just been torqued into the aluminum so I guess you'd say it's somewhere between an educated guess and superstition.
 
Dakota
I read an article on leather bedding using a thin sheet of leather . I can see how leather would form and also grip . Never tried it though .
 
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