Am about to shoot my re barreled Hepburn in 30-40 Rem for the first time and I know it has probably been discussed (just couldn't find it) before but what is a good break in procedure?



JMH

I've used several techniques & found the best & fastest method is the following from Lee Shaver.
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Excerpt from “Breaking in a Barrel” by Lee Shaver:
     Several years ago, I developed a process for breaking-in barrels for lead bullet use that eliminated the afternoon of shooting and cleaning with jacketed bullet.  It began because I would occasionally have to get bad leading out of a barrel for a customer, and when you charge what a gunsmith must charge to stay in business you don’t want to spend an afternoon scrubbing the lead out of a customer’s gun.   
     What I learned was that when scrubbing lead out of a barrel, I could run a tight oily patch through a few times and then take the patch off the jag.  I would then unroll a little 0000 steel wool and cut a piece the size of the patch.  Place that over the patch and then run it all through together.  (The proper fit is when you have to bump the rod a few times with the palm of your hand to get it started in the bore.)  When you shove that steel wool over a patch through the bore of a badly leaded barrel, it may sound like paper tearing as the lead is ripped out of the barrel in a pass or two.  I can clean the lead out of the worst barrel in about ten or fifteen minutes that way, and an average leaded barrel will be clean in a few strokes.
     After using this technique for a while, I began to notice that the rifles that I was de-leading that way seemed to lead less afterwards, which got me to thinking.  We use fine steel wool on the outside of old guns all the time to do some cleaning or spot rust removal, and it does not damage the surface of the steel.  It just scrubs it.  Which lead me to consider the fact that we are trying to break in a barrel by smoothing the surface without cutting, and it seems to me that process would go much quicker if we used something on the inside of the bore that was closer to the hardness of the barrel instead of lead or copper.  So, I started trying the steel wool and oiled patch technique on new barrels before shooting them.  I use it about as tight as I can get in the bore and wear out a steel wool pad or two in about 15 minutes, then I go and shoot the rifle.
     How well does it work you might ask?  On a few occasions, I have built a new rifle and taken it to a match without ever having fired the rifle.  All have performed flawlessly in their first match and several times I won the match or set a record with them.
Lee

By the time I shoot several types of bullets and various types of powders and different powder charges and bullet alloys and subsequent cleanings and breech seating depths trips back and forth to the range and setting up etc etc and finally have a new barrel shooting good enough for match shooting, I am the one that is broken in, not the barrel.

Mike Rock used to recommend nothing but JB bore paste and paper patches cut from blue shop towels....

Thanks for all the suggestions guys. So I was finally able to call and talk with BRC and he said no prep required and just shoot it. So it's his barrel and I guess he would know so I am going to do just that and see what happens. But I have the info to use if I need to.




JMH

I wonder how much it matters whether the barrel has been cut rifled or button rifled?  Ernie Stallman of Badger barrels recommended the jacketed bullet break-in procedure for his barrels and said that they would break it in quicker than shooting with lead. He said if you didn't do that, it would take about 500 rounds before his barrels were broken in.  Badger barrels were cut rifled

I think the point of a "break-in" is to get the barrel burnished to a point copper or lead is no lomger being embedded in the surface of the lands and grooves. Obviously a cut barrel will be rougher and require more to get it smooth than a buttoned one. A PhD engineer I once worked for used to say when we cut steel it is really "ripping" it on a microscopic scale, some techniques will leave a better finish than others but no surface is truly smooth. The thing to prevent is getting too much fouling with layers of carbon and gilding metal between cleanings as the barrel "wears in". In fact, fouling will prevent the steel surface of the bore from being burnished so the barrel will never be "broken-in".