Heat generated from barrel use creates heat waves in sights
Rain fell for hours last night in Camp Perry, Ohio. The night before competitors shoot the Palma Matches; where they will fire 30 of their 45 shots from the field and NOT the raised firing points. It could cause problems for some.
Port Clinton, Ohio - There are several types of rifles here at the NRA National Long Range High Power Championships. But no matter what the rifle, there are only two types of sights; metallic and any. Metallic sights are what you find on a gun fresh out of the factory. Any, typically, are scopes that magnify the target. What we've seen over the past few days, however, were attachments to the end of the scopes.
In search of an answer, we decided to dig into our long range research center; 6-NRA Long Range High Power Rifle champ David Tubb.
"It's a mirage shield."
Shooters encounter heat plumes in the field all the time. A rock, a sprinkler head, or an empty piece of ground down range generates more heat than a patch of grass. The heat rises in that specific area and creates a possible disruption with your shot. Most people know all about that. The heat generated by your rifle barrel, however, is an entirely different case all together.
A rifle right off the rack is as room temperature as the shoes on your feet. But put a few rounds though it and the barrel gets hot. Hot enough to cause some trouble is you're not prepared.
"You get heat waves that emanate from your barrel and that displaces your sight picture. It's not healthy," he said with a laugh.
But your options are not limited to a big circular tube attached to the end of your scope. Tubb, for example, clamps a small piece of aluminum threshold molding to the picatinny rail of his Tubb Gun. Others, like John Whidden, go with a band that stretches from the end of the scope to the end of the
barrel. Each of which dissipate heat waves with great success.
"But you don't always need one," Tubb chimed in. "If we had a wind blowing here, right to left or left to right, the mirage would dissipate. But that's not the case here today and that's why you're seeing the shields."
The things you learn at a rifle match.
For more on NRA's Competitive Shooting Programs, visit their website at compete.nra.org