Glass bedding a rifle involves various techniques, from applying a thick epoxy to reinforcing specific areas. The method chosen depends on the desired outcome.
Applying glass in the stock mortise—it’s
better to have too much than too little.
Glass bedding serves multiple functions; in wood stocks, it acts as a sealer for exposed wood, while its primary role in both wood and synthetic stocks is to ensure the action makes full contact with the stock, preventing any movement that could compromise accuracy.
With extensive experience bedding hundreds of rifles, the process has become almost second nature. However, even those new to bedding can achieve professional results by following straightforward instructions.
Understanding Glass Bedding a Rifle
Bedrock Glass Bedding Kit
Glass bedding should not be seen as a fix for poor inletting. A poorly inletted stock will remain inadequate, even with glass bedding applied. The glass should be a thin layer of epoxy, not an epoxy stock.
Since most stocks encountered are factory replacements, efforts should be made to match the manufacturer’s glass bedding. The hallmark of quality work is indistinguishability from factory bedding. This standard should be upheld by any gunsmith bedding kit or DIY enthusiast performing a standard glass-bedding job.
Ensuring Proper Fit of the Gun Barreled Action
Modern actions come in various lengths: super short, short, standard, and occasionally magnum length receivers. After acquiring the stock, verify that the correct stock has been received before applying the bedding compound. A dry fit is essential to ensure all components fit correctly, eliminating surprises once the glass is set.
Cleaning up before the glass cures can
prevent future headaches; a chisel may be necessary to
remove hardened glass.
If the gun barreled action does not fit smoothly, do not force it. Misfits can occur for several reasons. Even if the action length matches, a magnum barrel is typically larger in diameter than a standard rifle barrel. Avoid making alterations to the stock; instead, contact the manufacturer to confirm that the correct part has been received. Exchanges are often possible if the stock remains undamaged.
Assuming all components fit correctly, disassemble the small parts from the receiver. A useful trick is to photograph the assembly for reference during reassembly.
For glass bedding, only the action, action screws, and floor plate assembly are needed. Small parts like the magazine box and trigger should be removed, or if unsure about reassembly, the areas in question can be filled with clay.
While disassembling, examine the existing bedding job. This serves as a guideline for the new bedding and indicates whether the stock has withstood recoil from repeated firings. If the existing bedding is intact, the same method can be used. However, if it shows signs of failure (cracking, breaking, or softening from harsh cleaning agents), alternative bedding methods should be considered.
Preparation for the Gun Bedding Compound
Magpul Hunter 700 Stock for Remington 700
Short Action
The bedding compound will flow into every crevice of the action, and if it enters unwanted areas, removing the action can be extremely difficult, potentially damaging the gun stock or receiver.
To prevent the bedding compound from entering these areas, fill voids with clay. Children’s clay is recommended for its easy cleanup.
Next, degrease the action and apply two layers of common masking tape on the front and sides of the recoil lug. This tape creates a small gap around the recoil lug, facilitating easier removal of the barreled action from the stock.
The Critical Step: Utilizing Release Agent
Release agent becomes essential during the glass bedding process. Many manufacturers of bedding compounds also offer release agents; however, Johnson’s paste wax is preferred for its ease of use and minimal residue. Apply a generous amount to fingers and spread it evenly over the action and barrel. When in doubt, apply more wax.
Before and after: The lower target shows a rifle’s
glass bedding failure causing erratic
groups; the upper target demonstrates a
properly bedded rifle.
Do not forget to apply wax to the action screws, floor plate, and any components that will be installed while the compound cures.
The bedding compound is typically a two-part epoxy that must be mixed in equal parts. Using craft sticks or Popsicle sticks, mix the bedding and apply it to the stock. A gel-type bedding compound is preferred for its reduced mess and consistency similar to peanut butter.
Use a disposable plastic cup for mixing, ensuring it is not waxed, as wax can hinder proper curing. Follow the mixing instructions precisely; improper curing will necessitate removal and re-bedding.
Disposable rubber gloves are advisable, as the bedding compound is extremely sticky and difficult to remove without them.
While some gunsmiths tape paper towels to the stocks for cleanup, this may be unnecessary with careful application. However, applying a thin layer of wax around the area where the glass is applied can facilitate cleanup.
Most fiberglass and wooden stocks require minimal preparation, aside from scraping off any paint or finish from the inletting to allow the bedding compound to adhere. In contrast, popular plastic stocks need to be roughed up to ensure proper adhesion, as the bedding compound does not bond well to plastic. Drilling small angled holes can help secure the compound in place.
Applying the Bedding Compound in the Recoil Lug Area
If no recesses need filling aside from the recoil lug area, begin by placing a compound amount approximately half the size of a dime into the recoil lug area, focusing on the rear of the cutout. While it is possible to fill the entire recoil lug area, this adds unnecessary weight and compound. The compound should mimic the manufacturer’s application.
Free Floating the Rifle Barrel
Most shooters and hunters understand the concept of free-floating barrels, though opinions vary on where the free float should commence. Some gunsmiths bed only the action, allowing the barrel to float entirely, while others bed the action and the front cylinder of the barrel, permitting the remaining barrel to float. Both methods can yield excellent results, depending on personal preference and experience.
Typically, bedding compound is only needed in the recoil lug and rear screw areas. However, the barrel must be supported while the bedding compound cures to ensure it remains free-floating. A spacer made of thin cardboard, approximately .032 of an inch, can be used to maintain proper clearance. The placement of the spacer depends on the gunsmith’s technique and the specific firearm.
Some gunsmiths position the spacer at the fore-end tip; others place it at the cylinder section of the barrel. Once the shim is in place, tighten the action screws, starting with the rear screw and then snugging the front screw. Avoid using a torque wrench for this process. If the action has three screws, the screw behind the magazine should be tightened just enough to prevent rattling.
Tip: The Pachmayr Gun Screw Set is a comprehensive 277-piece set that includes a dozen each of 23 screws suitable for various firearms.
Cleanup & Reassembly of the Rifle
Once the bedding compound has cured, the rifle is ready for disassembly and final cleanup.
RangeMaxx Magnetic Gun Cleaning Mat
Remove the action screws; a gentle tap with a plastic or leather hammer on the screwdriver handle can assist in loosening stubborn screws. The same mallet can help separate the barreled action if it does not release easily from the bedding compound.
Tip: The RangeMaxx Magnetic Gun Cleaning Mat allows for thorough cleaning without the risk of losing small parts.
A 5/8 inch dowel inserted into the back of the receiver provides an additional handle, distributing even pressure on the barreled action during removal. The barreled action may “pop” when released, indicating a tight fit with the bedding compound.
If bedding compound has seeped into the action screw holes, use a round file or appropriately sized drill bit to clear them. Most screws are 1/4 inch, so a 5/16 drill bit should provide ample clearance.
Remove any clay remnants from the rifle’s recesses. Reassemble small parts using the earlier photo for reference, then tighten the screws. Testing the rifle’s feeding with dummy rounds is advisable.
If all checks out, the rifle is ready for the field.
Bedding a rifle is not overly complex but requires careful planning and attention to detail. The results from a properly bedded rifle are well worth the effort.
