Let’s say a customer brings you a Remington 700 with a Vortex Viper HS LR Scope mounted on it and wants you to make it more accurate. The customer mentions that they have had little success hitting targets beyond 100 yards but wants to go on a hunt where they will need to hit 200 plus yards. How would someone go about doing this? Well, one of the first things I would like to do is get this person on a rifle I already know is capable of achieving this task. My purpose for this is to see if the shooter has the ability or knowledge to operate at those distances. If so, then it may be time to start looking at the rifle.
After a quick inspection of the rifle, making sure it is safe to operate, I will confirm zero and test fire it to see if the scope or rifle have any noticeable issues that are easy to correct. It’s possible that the scope just wasn’t zeroed correctly in the first place. The next thing I will be inspecting is the barrel and muzzle. Damage to the muzzle can affect accuracy so if I see any noticeable issues there then I would consider fixing the barrel’s crown. Now that I’m satisfied there, I’ll begin to inspect the rest of the barrel. Using a bore scope I will look for damage to the rifling and see if there was any copper fouling that may be affecting accuracy. If copper or nitro fouling was the issue, I would use Birchwood Casy Bore Scrubber in the barrel to start the cleaning process followed with the appropriate patches, jags, and bore brushes to finish cleaning out the existing rifling.
If the crown on the barrel is chipped my next steps may vary depending on where it is and how deep it is. If it is chipped where the rifling ends, then I may just use a brass crowning tool and some fine grit compound to lap the barrel at the muzzle until I have worked it out. Otherwise, if the chip is deeper and not at the rifling’s end I may use a 45 degree crowning tool to clean up the center of the crown or an 11 degree crowning tool to clean up the entirety of the muzzle. It is also possible that I may need to remove a small section of the barrel at the muzzle end.
Taking a look at the bore now, I begin to look for cleanliness and possible rust, especially rust pitting where it had sat for so long that it began to eat into the metal. This is a big deal anywhere on the barrel, but it matters most at the bore because that is the spot that has to take most of the pressure when a cartridge is fired. If the rust pitting is bad enough, I would usually recommend that the customer purchase a new one and have it installed for safety reasons. I have had to tell one or two people in the past that their options were a new barrel or cleaning it up and making it wall art, never to be fired again. Usually when they look at the options they decide to get a new barrel and this is when it is important to inspect the lock up of the bolt lugs to the chamber. The same receiver’s shoulders have similar wear to the existing bolt lugs, and they work fine but when a new barrel is installed, they may need to be worked in a little to ensure the lugs meet the chamber recesses.
By starting a process called blueprinting, you ensure the barrel is true to the receiver and that the locking lugs are true to the barrel. In doing this I will also need to make sure the recoil lug is perfectly flat on both sides. Truing up the Bolt surfaces may help it lock up to the new barrels chamber by ensuring it has full contact with the shoulders in the receiver and this should then aid in making the rifle more accurate. One useful technique when lapping Remington action is using a bolt lug lapping tool, action bushings, a piloted reamer, a piloted tap, and bolt face cutters with a guide to be sure everything has cleaned new surfaces for better lock up. If you wish to see how to use those tools to properly achieve the action lapping, YouTube has a few videos with my favorite being by Larry Potterfield and Midway USA.
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