new barrel break in

[Coyboy]

guys I wrote this a few years ago and stand buy it for the most part couple things I learned since then, read the follow up comments forum at the end of the article because the discussion is as informative as the article.

Custom Barrel Care At 17X

Bart, I don't know of a single person in the know, who claimed breaking in a barrel made them inherently more accurate, if you read my article I state reasons for brake in and non of them involve making the barrel "more" accurate. but I do believe brake in happens weather you do anything to that barrel or not.

I want my barrels to stabilize at a consistent velocity before I do a substantial load development, and this does require a certain number of rounds be fired down the bore. Gales article is got to be near 30 years old and he bases it on "break-in making a barrel more accurate" I'm not sure his excuses that this is all to sell more barrels has one ounce of validity. We have all had barrels that shot the first 5 bullets out of them into a 1/4" so a barrel does not need to be broke in to shoot well, BUT a Barrel will physically change enough in the first 100 rounds to; increase velocity, thus changing the "tune" of that load.

I cringe every time I see his article referenced as the end all be all in barrel conditioning.

 

[FEENIX]

Deleted!

 

[FEENIX]

To me, FEENIX asks:No, but every hand-held shoulder-fired arm gets its own shot dispersion added to by the dispersions of human physical behavior. To date, there's no tolerances set in the shooting sports as to what's the worst human dispersion that's allowed to test an arm for accuracy.

Duly noted ...

As long as human factors are involved it will always complicate things.

Perhaps an opportunity for you to set the standards. Good luck!

 

[Bart B]

BUT a Barrel will physically change enough in the first 100 rounds to; increase velocity, thus changing the "tune" of that load.

What's the physics behind that velocity increase? If every bullet fired causes a microscopic amount of barrel wear, would not that cause less resistance to the bullet starting out and lower pressure therefore lower velocity?

And wouldn't a velocity increase only make a group print a bit higher than a velocity decreace? I don't understand how faster bullets would cluster tighter.

I've had 1000-yard groups where some bullets that left faster than slower ones print lower and slower ones print higher than the higher ones. Difference isn't much, only a couple inches.

 

[Coyboy]

What's the physics behind that velocity increase?

I don't understand how faster bullets would cluster tighter.

I've had 1000-yard groups where some bullets that left faster than slower ones print lower and slower ones print higher than the higher ones. Difference isn't much, only a couple inches.

To answer your comments 1st one; I'm not an expert at internal ballistics, i'm reporting information I have gleaned and others in the industry have gleaned over years of work with thousands of custom barrels. I could give you my theory on this but likely it would just raise more illogical questions from you. You obviously didn't read the entirety of my article and the follow up discussion or you could have answered that from that info.


2nd. I never said faster bullets will cluster tighter, no one in the thread has stated that other than you. So what is your misconception about all this that you have these preconceived notions in your head which are so misleading?

3rd Your 1000 yard groups are affected by so many things that it is impossible to dictate what causes this or that. Your ability for one, condition changes as far as wind direction and velocity for 2, your ability to load ammo for 3 and I'm not just referring to speed of projectile but all the intricacies of brass prep and bullet run-out ect. Scope parallax, mirage, the list goes on.

So what is it that you concluded in your testing since you fail to account for anything other than the speed of the bullet?

 

[FEENIX]

 

[Bart B]

Jim See, I did read both pages in your article. You're making assumptions I didn't read it.

How does a barrel physically change enough in the first 100 rounds to; increase velocity, thus changing the "tune" of that load?

If that's too complex for you to answer or understand, so be it.

 

[FEENIX]

(C&P extract from Gun Barrel Break-In (Seasoning) Procedure)

WWIW ...

Brand new gun barrels will have microscopic burrs on the surface of the bore... they're left over from the machining processes used to make the barrel and are completely normal. These burrs wear themselves smoother and smoother each time you fire your gun... Its a process that old timers sometimes call "seasoning", and when a barrel is fully seasoned, it will be shooting with its best accuracy and velocity.

 

[Bart B]

Brand new gun barrels will have microscopic burrs on the surface of the bore... they're left over from the machining processes used to make the barrel and are completely normal]

Those burrs are not lapped out when the barrel maker makes their bore uniform in diameter to the one ten-thousandth of an inch?

 

[FEENIX]

Those burrs are not lapped out when the barrel maker makes their bore uniform in diameter to the one ten-thousandth of an inch?

It's a C&P from link provided above, since you know something they don't and have problem with the inaccuracy of the statement, address it to them directly.

 

[Coyboy]

Jim See, I did read both pages in your article. You're making assumptions I didn't read it.

How does a barrel physically change enough in the first 100 rounds to; increase velocity, thus changing the "tune" of that load?

If that's too complex for you to answer or understand, so be it.

Well Bart thats great you read 2 pages of a 3 page article. Now read it and the 6 pages of discussion after the article and it will answer all you questions you seem to think I don't understand.

Custom Barrel Care At 17X

http://www.longrangehunting.com/forums/f5/custom-barrel-care-17x-jim-see-50118/#post339479

But I also understand from this thread alone your reading comprehension skills really suck so you might want to read it twice think about it for at least a day and then read it again before you continue to ask questions you think you know the answers too.

And don't get me wrong MY job isn't to come here and argue with someone who either thinks they know it all, or is to hard headed to see I am trying to inform the general guy reading this thread. If you don't understand what I've explained or never seen a barrel speed up during "brake-in" then you obviously have so little experience in the realm of shooting that it is laughable you pass yourself off as being so knowledgeable about the subject.

 

[FEENIX]

Jim,

Be careful, it's not worth it ... I don't think you're alone in your assessment of the matter.

Cheers!

Ed

 

[Bart B]

But let's say you load 75 cartridges exactly the same and fire them through a new bore. At the same time you did a few shoot and clean, and the barrel is cleaning up easily. You will notice that the velocity readings of these 75 bullets may be a little erratic, and will most likely increase through this period of use. After the 60th or so bullet the velocity readings should equalize and may be up to 50 fps faster than the first 20-40 bullets. This was not my finding, but pointed out to me by a friend who has broken in many more barrels than I have. Since that time I have seen it enough to believe it.

I've done that enough to not see it so therefore I don't believe it. Some folks realize that two people conducting the same test with different stuff will get different results. There's a difference, but the stubborn one won't admit it. I do.

Jim See, ain't it nice to have someone around whom you think you're better/smarter than? And you're not even thanking me for being around so you can feel that way.

 

[FEENIX]