Better accuracy from bolt action rifles

Posted July 11, 2012 at 2:46 pm

For many firearms deer hunters in Kentucky, the tool of choice is the bolt-action centerfire rifle.

With a little gunsmithing work and the right ammunition along with pre-season shooting practice, deer hunters will be ready to close the deal when a shooter buck walks into range this November.

The first step is to find a competent gunsmith who can accomplish three procedures: adjusting the trigger pull, free-floating the rifle’s barrel and bedding its action.

Most bolt-action rifles, new ones and many used ones, will have a very heavy trigger pull, which makes it practically impossible to shoot accurately.

“The more force it takes to pull the trigger, the more the gun moves. On average, trigger pulls are set at five to six pounds at the factory,” said gunsmith Mike Ezell, who lives in Auburn, Kentucky and specializes in rifle work.

There are two options: adjust the factory trigger or replace it with an after-market trigger.

“The ideal trigger pull is about three pounds, but whether or not that can be done is dictated by the design of the trigger. Some triggers can’t be set that low,” said Ezell. “Safety should always be the first concern when adjusting trigger pull. Installing a good after-market trigger is the best option for everybody’s safety.”

Trigger creep, or the distance the trigger must travel before the gun fires, can be detrimental to accuracy as well. “There has to be some creep, but your rifle should have a smooth, clean trigger pull,” said Ezell.

In recent years, the manufacturers of the most popular brands of hunting rifles have improved the quality and adjustability of their triggers.

The next step to improved accuracy is focused on getting the rifle to shoot more consistent groups of shots on a target. “I’ve never seen a gun that didn’t benefit from free-floating the barrel and glass bedding the action,” said Ezell. “It’s all about barrel harmonics.”

The goal is to minimize the factors that contribute to erratic barrel vibrations, one major cause of inconsistent groups. Barrels vibrate in a circular motion as the bullet travels towards the muzzle, riding the grooves cut into the rifle barrel.

Free-floating a rifle’s barrel is especially important on rifles with wooden stocks, since moisture and humidity can affect where and how the wood touches the barrel, causing inconsistent vibrations. Gunsmiths use files to remove wood in the barrel channel of the forend of the stock, so the barrel “floats.”

Glass bedding of the action should be done at the same time as the barrel work. “You don’t want the action to move in the stock,” said Ezell. “The action should be solidly mounted, without twisting or stress, so it fits like a glove.”

A loose screw will also cause erratic groups. The screw that holds the action in place should be tightened to the correct torque setting. The setting may vary from rifle to rifle, even those of the same make and model. Find the exact tightness of the receiver screw and there will be a noticeable effect on the size and consistency of shot groups.

Ammunition is another important accuracy consideration.

While reloading offers the hunter an opportunity to tailor ammunition to a specific rifle, there are other options that are less expensive and time consuming. Select ammunition with the proper bullet performance on white-tailed deer and try several brands to see what is most accurate in your rifle.

Today, there’s a much wider variety of factory-loaded ammunition available, including cartridges loaded with premium bullets. In the past, premium bullets were only available to hunters who reloaded. Don’t overlook some of the reduced-recoil loads, which sometimes deliver much better accuracy.

New rifles have a break-in period, maybe as much as 100 rounds, before they deliver optimum accuracy.

Proper cleaning of the rifle’s bore from the beginning is imperative. The bore of a new rifle should be cleaned before firing it and cleaned about every 20 shots in the beginning.

Clean the rifle from the breech, never the bore, with a one-piece cleaning rod. If the barrel crown is damaged it will ruin the rifle’s accuracy. Even the smallest nick at the muzzle will allow gases to escape to one side, affecting the bullet’s flight as it leaves the muzzle.

Cleaning supplies should include bore solvent, cotton patches and bronze rifle brushes. Never use stainless steel brushes because they damage the barrel’s rifling.

The final step is sighting in your rifle and practicing at various distances in situations similar to how you will be hunting.

All this attention to detail along with the time and money invested will pay dividends for many years to come. You’ll have an accurate rifle that you can hunt with for a lifetime.

Several wildlife management areas in Kentucky have 100-yard shooting ranges open to public use. For information, log on to the Kentucky Fish and Wildlife’s homepage at fw.ky.gov. Click on the “Maps and Online Services” tab, then “Other KDFWR Maps” and scroll down to “Shooting Ranges.”