Rifle bedding is fundamental to rifle accuracy. The term bedding refers to the fit and stability of a barreled action within the rifle stock. If the fit and stability of the metal work in relationship to the stock is poor, the rifle will be in-accurate. Bedding a rifle with epoxy resin is the optimum method of obtaining a correct fit, long term stock stability and optimum rifle accuracy.
In order for a rifle to shoot accurately, the number one rule is that everything needs to be the same with each shot. There are several variables to rifle accuracy and each variable must be addressed. The shooter needs to be in the same position for each shot, each cartridge must be the same as the one before it, and the scope must hold the same zero while the rifle needs to produce the same results each and every time.
With every shot, the barreled rifle action moves and vibrates within the rifle stock. The best way to picture the barrel is by using the analogy of a baseball pitcher. As the pitcher throws his ball, the slightest difference in his point of release will change the point of impact at the batter. The rifle barrel is just the same and "whips" with each shot. If the barrel is unable to whip the same way each time, the bullet will strike to a different point of impact.
The rifle action also undergoes movement and stress. When a shot is fired, the pressure of the cartridge produces recoil within the stock, the action is forced backwards and then returns forwards. If the action does not return the same point after each shot (this term called "battery") then the rifle will be in-accurate. If any areas of the stock are pinching or exerting excess pressure against the barreled action, accuracy will be poor.
To set up the best platform for accuracy potential, gunsmiths, custom rifle builders, target shooters and hobbyists "bed" the rifle action and free float the barrel. Bedding involves filling the gunstock with a strong as steel resin, the action is then set down into the resin which when dry, creates a mirror image of the action. The mirror image of the action is a precise bedding platform which allows the action to recoil and return to battery with each shot. This explanation is however oversimplified as several areas of the action need to be relieved to create stress free points and allow for the piston like movement of the action within the stock. (see MatchGrade instructions)
Free floating the barrel involves removing all wood or plastic along the barrel channel so that the barrel has no contact points with the barrel to interrupt its natural whip. The only point of contact should be the bedding under the barrel "parallel" closest to the chamber. This helps ensure that the action is not having to hold all of the weight of the whole system. Never ever free float a plastic stock without bedding the rifle. An unbeddded free floated plastic stocked rifle may produce groups as wide as 2 feet at 100 yards.
Unfortunately, bedding is too costly a procedure for most rifle manufacturers to perform. The only exceptions are sniper rifles built for the military as well as certain semi custom model rifles. On typical production sporting, varmint and tactical/target rifles, the rifle is assembled in such a way that the barrel is forced upwards at the tip of the forend. This point of force is called pressure point bedding.
Pressure point bedding will usually allow a rifle to shoot groups of between 1.5 to 3" at 100 yards. This level of accuracy is adequate for close range shooting using a cold barrel but hopeless for moderate to long range shooting. Pressure point bedding is counter productive to accuracy when firing multiple shots- as the barrel heats up, it move upwards due to the force of the pressure point which results in stringing shots. On wood stocked rifles, pressure point bedding will eventually become a problem as moisture shifts the stock around.
To check whether your rifle is bedded, remove the barreled action from the stock. The bedding is instantly recognizable as a layer of resin that appears as a mirror imprint of the action. Be aware however, that not all bedding jobs are a success. If the rifle has been bedded prior to your ownership of the rifle, but the rifle is in-accurate, it may well need to be re-bedded with better attention to detail.
Now you know what bedding is, have a look at our how to's for stock and action bedding from the links below;
Rifle Bedding Instructions
Synthetic Stock Stabilizer Instructions
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