Re: Barrel Break-In
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Skunkworks</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: flyboy</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Skunkworks</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeff in TX</div><div class="ubbcode-body">This may be hard to swallow but barrel break-in is a waist of time and effort. Before jumping the gun lets look at this objectively.
• 99.9% of shooters don’t have access to a quality bore scope to view the interior surface of their barrels.
• Without a bore scope to view the interior surface of your barrel what exactly are you trying to fix by a shoot and clean process?
• Does shooting and cleaning cure all barrel imperfections if they exist? If yes, how?
• Now I do recommend cleaning your rifle after you purchase it to clean out all of the junk, oils and grease from the factory before shooting it.
• If there are burrs or machine marks from the machining process in the barrel where are they located? Without a bore scope again you have no idea.
• P
ushing a cotton patch with solvent or a bronze brush down the barrel will do what to remove a 416 stainless steel or chromemoly metal burr or machine marks?
• Last time I checked, 416 SS or CM is much harder than a cotton patch, bronze brush and is most likely impenetrable by most bore solvents.
• Yes it will remove copper fouling caught by the metal burr, but how will it remove the metal burr.
• How many shots will it take to remove the burr or imperfection and how will you know when the barrel issues have been corrected? Is it always x-amount of shots?
For those that perform this shoot and clean ritual after each round or every few rounds I assume it makes you productive, but without a bore scope aren’t you doing this blindly?
For those interested I did a lot of research on barrel break-in processes back in 2001/2 time frame after trashing a new Shilen SS Match barrel after 400 rounds of shooting moly coated bullets. I wanted to understand what went wrong. In my research I spoke with metallurgists, internal ballistic engineers, some of the premier gunsmiths and some of the top barrel makers in the country to understand what if any a barrel break-in would actually do if anything. In the end I learned that barrel break-ins are a waist of time and effort as well as a ton about internal ballistics. If anyone is interested in the write up send me a PM.
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There is a very common and unfortunate misconception about barrel break-in. The idea behind the process has little to nothing to do with the actual rifling, burrs or machine marks in the barrel, but is intended to concentrate on the throat. After chambering, the throat could be a little rougher than it should be. When a round goes off in the chamber, the heat atomizes a portion of the copper from the projectile and this atomized copper adheres to the first surface it comes into contact with, in this case, the throat. Understanding that hot copper sticks to hot copper, it doesn't take long to build up a considerable amount of fouling in the throat and ultimately, adversely affecting accuracy.
The process of barrel break in ensures the smoothing of the throat to the point that it collects less fouling. In high quality barrels, it takes less effort to do, but obviously, all barrels are not created equally. Barrel break in is intended to ensure a longer throat life than it does a rifling life. For factory or lower quality barrels, some have found that fire lapping helps smooth the rifling, burrs and machine marks, which is a different process altogether. Does barrel break-in amount to anything? In an effort to protect your initial investment, what could it hurt? After all the time and care that goes into building high quality rifles, nothing leaves my shop without having the barrel break-in performed and I do this without a borescope. It's simple enough to watch how the patches come out to know whether or not the throat has smoothed enough to stop collecting large amounts of fouling... </div></div>
Thats all fine and good, but can you PROVE that it makes an appricable difference? </div></div>
Not that it contributes greatly to the discussion, but I've seen cross sectioned barrels that had the same number of rounds through them, some that were properly broken in and some that weren't. The throats in the barrels that were broken in had considerably less erosion than the ones that were not. Does this prove anything? Maybe it does and maybe it doesn't. But can you prove that it doesn't make an appreciable difference? If you had the opportunity to take an extra step that might make a difference in your everyday job, would you take advantage of it? </div></div>
Nope, the steps of my everyday job are pretty well laid out infront of me and require very little extra on my part, and thats because someone took the time to prove them with thier blood.
And as for the barrels, unless we're talking cleanroom, scientific studys, what has been seen on one barrel verses anothing is irrelevent. All other conditions must be the same to the degree of the barrels needing to have been the same laped tube before the eventual seperation and chanbering.
