I just recieved a new 700 BDL deluxe in 7mm Rem Ultra Mag. I want to do everything I can to enhance and maintain the accuracy of this weapon. I have heard of lapping and other barrel prep techniques, but am not familiar with any. Does anyone have any suggestions how to prep this weapon for the best possible accuracy? Also is it possible to change the drop out plate to a detachable magazine?

An old friend of mine used to clean the bore with J-B after each shot for the first 10 shots. Then he cleaned it after 5 shots for the next 20. Then he considered it broken in. I used a similar method on an AR-10 with very good results as far as accuracy.
You can find a hundred different answers.

Before you "BREAK IT IN", shoot it to see how well it groups NOW!! It MAY NOT NEED any special treatment.

Harry Pope used to say that more rifle barrels have been ruined with a cleaning rod than any other way, and this is still true today according to some custom barrel makers and riflesmiths.

Break-in is important, and there's more at stake than fundamental accuracy. A carefully-executed barrel break-in eliminates tiny burrs inside the bore, reduces rough spots, and enhances smoothness and uniformity.

I've owned a lot of rifles over the years, and I started following a prescribed break-in proceedure on all of the new ones starting in 1991. I noticed right away that copper fouling was significantly reduced, accuracy was more consistent, and velocities became more uniform across the board. Some barrels benefit more than others, but in my experience the gain is always there.

You'll need a one-piece rod (Bore Tech or Dewey), bronze-core brushes (Pro Shot) of the proper size, cotton patches of the proper size (Pro Shot), a good bore guide (Sinclair), and a supply of Shop Towels (auto parts store).

I recommend that you start the break-in proceedure right away, before you fire a single round. Clean the barrel first with a good solvent (Shooter's Choice/Birchwood Casey Bore Scrubber/Butch's), dry the bore and chamber, wipe off the crown, wipe off the cleaning rod, then proceed to the first shot. A fresh, clean patch should always be pushed through the bore just ONE time: Through the breech and out the end of the barrel. Don't draw back into the barrel the gunk that you're trying so very hard to remove in the first place! I use a seperate bore mop on a short handle with which I push in an oversized clean patch (slightly wet with solvent) to clean the chamber (an often negelected proceedure), followed by a clean patch to dry.

I clean between shots for the first ten rounds, after every other shot for the next ten, after every third shot for the next, ten, etc., until I go through fifty rounds. I avoid the use of JB until the FINAL cleaning, and then I'm very careful to get every last bit of it out. I follow with a patch and Kroil as a final proceedure. Always push a dry patch through before you fire the rifle again, and also dry-patch the chamber.

With all due respect to the memory of Harry Pope, time hasn't exactly stood still since the glorious "good ol' days" when he was turning out barrels. Today's barrels are better than the ones he made; we know more about accuracy than they did in Harry's day; we know more about the value of proper cleaning (and cleaning proceedure) than they did in Harry's day; and today's cleaning equipment is far, far more advanced and safer to use than it was back in Pope's era.

There's no reason NOT clean properly these days, or to break in a barrel. The understanding, technology, and equipment is in place to get the job done safely and thoroughly if you're willing to put in the effort.


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The post by Allen Day is right on the money. I break in all rifle barrels with about the same procedure. I think it DOES help keep fouling down and improve accuracy to some degree.

Comments by the likes of Ross Seyfried notwithstanding, breaking in a barrel is worth the trouble. (Though I cannot think of anything more boring or tedious.)

There has to be a reason that many custom barrel makers send instructions on barrel break in with their products these days.

R F

With respect to abrasive lapping, you cannot properly hand-lap a barrel after it has been crowned and chambered. Lapping will cause belling of the barrel at both ends. Aftermarket barrel suppliers hand lap, and then remove the oversize end sections when the barrel is cut to size. Chambering removes the belling in the breech end. You can, however, vigorously clean with JB to remove fouling and slightly polish the interior of the barrel without damage. As already stated, use a good rod and bore guide.

Also worth mentioning is fire lapping. This is firing bullets coated with increasingly fine-textured abrasives down the barrel. I would not do that procedure unless the barrel was extremely rough, I was planning on rebarreling anyway, and it was a last-ditch effort to make the barrel shoot before giving up.

You've gotten great advice in this thread on how to break in a barrel. I'd second those recommendations. Good luck and let us know how it shoots.

I prefer Flitz paste over JB for all my jobs. The polish is higher, and in prolonged tests I have done I am unable to detect any wear using it over JB. If/when I do any kind of break in, I run the Flitz through the bore with a patch about 150 times or so, change out from time to time with a new one. Just my 2 cents.

I've fallen in line with a procedure similar to Allen D's, but I'm skeptical that we're all chasing some voodoo that got started by some benchrest guy and has become the gospel. Has anyone done controlled tests, using borescopes to determine whether barrel break in is myth or reality? We all have anectdotal hunches, but let's face it, once we've broken in a barrel we don't have anything to compare it too...Like I said, I've blindly bought into the whole thing but like Moly, Cryo, Echinacia, St. John's Wart and host of other things people used/took on faith it ain't always so once things are put to through the rigors of the scientific method.....we should be starting with the null hypothesis and then use data to determine otherwise.....or not....

I follow a protocol as Allen Day does, mine was developed by Kenny Jarrett for his barrels. I learned it at one of Kenny's barrel cleaning and rifle maintenance seminars (I caught this one at an SCI Convention).

Kenny's rationale for the breaking in is to blend the two different zones of machining from the leade to the barrel proper, and to gain the benefits that Allen Day mentions above. He also recommends high quality cleaning components.

Kenny recommends a shoot one, clean for the first 20 shots, with a major cleaning after the first ten rounds. His cleaning regime uses Shooters Choice for the crud and Sweets 7.62 for the jacket fouling.

In the past I followed a one-two-three-five pattern as Allen describes.

My rifles are certainly not less accurate than my previous experience, but I don't know how much accuracy I can ascribe to break in. Kenny certainly has some compelling videos or barrel internals.

jim dodd

Rescurat,

You've got a factory rifle with a factory hammer-forged barrel; not button rifled, not cut rifled like match grade barrels from the likes of Hart, Lilja, Shilen, etc. You don't need any fancy lapping or prep work. Just clean the factory preservative from every metal part, inside and out. Always use a bore guide and never use one of those god-awful aluminum jointed cleaning rods. I prefer those made by Dewey. Use jacketed lead-core bullets for the first 20 shots...the initial barrel breakin. After that it's OK to use a solid copper bullet such as Barnes. Clean the barrel with a good copper remover solvent like Barnes CR-10. When the patch comes out without any telltale signs of blue (copper) lightly wipe the bore with a good gun oil to prevent rust until you take it out to shoot again. Don't forget to run a clean patch through the bore to remove that gun oil before your next shooting session.

Another suggestion before you get too many rounds through the barrel is to load up a dummy round with a bullet snug up against the rifling lands. Then you can use it to see how much throat erosion has taken place after a few hundred rounds of that overbore 7mm. Good luck and good shooting.

I think what Allen was saying, by saying ONE time, was that EACH patch should only go through one time, breech to muzzle & not drawn back through the bore.

Use as many as you need, but remove each one when it comes out of the muzzle, draw the rod back, put on another clean patch, repeat as needed....

Go to Shilen Barrel website and they post a proceedure for break in. Worked for me.

Thanks to all who have replied, Just a few quick questions. I am familiar with "FLITZ", but not J-B, is this an abrasive paste, creme or other? Re Moly coating, is the break in any different?