lapping new barrel

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How does the barrel look and shoot now?

I suppose a few swipes with some JB bore paste won't hurt, but barrel break-in isn't really necessary.
 
I haven't picked it up yet, on layaway. I plan to have everything ready. I want to figure out what I am going to do, then follow the plan.

I don't want to go through the breakin, then decide to lap it.

Not sure I want to lap it, or even if I should?
 
Clean it,sight it in and start shooting. If it doesn't group to suit you,use the JB bore paste that highorder suggests. Bore lapping is only necessary if the rifling was left rough from the factory.
 
I have read that lapping will also help with fouling, in that it prevents fouling.

Am I right in that you are suggesting that lapping is only for barrel that demonstrate a problem, and that lapping would not improve virtually all barrels?

That sounds cynical, but a serious question. I don't want to go so far as to harm the barrel, but I would like to get this gun shooting as well as I can.
 
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The only way lapping can be done accurately is if you do it using a lead lap cast in place to fit the rifling exactly.

Lapping with a tight patch and fine grinding compound will only round off the sharp edges of the lands.

I would never do it to a brand new barrel until I had first determined that there was something wrong with it that lapping might somehow fix.

Either with a Bore Scope, or by testing it by shoot groups with it first.

20 or 40 rounds through it will take care of any microscopic bur edges on anything.

Clean throughly every 20-40 rounds with copper solvent and see how much jacket fouling you get out of it.

If it fouls a lot, lapping with JB would maybe help.

BUt I sure would not do it before I even tried shooting it some.

rc
 
Lapping requires a lot of experience to do well (and is very time consuming) - you may make the barrel worse (and several others after) just gaining the experience to do it properly!:what: Lapping will probably enlarge the muzzle section of the bore so it will probably need shortening and recrowning after lapping. I would try fire lapping first unless the bore is real rough. Fire lapping won't damage your bore and will probably reduce fouling to some degree.
 
Lapping is to remove accuracy robbing roughness left by dull rifling tools. Unless the barrel is very rough causing it to foul quickly, leave it alone,IMO. Lapping does not create accuracy.
 
+1

Neither dies Tubbs fire lapping..

You have about a 50/50 chance of making it shoot worse.

rc
 
I was a metal finisher for years. I understand the effects of removing metal on tolerances. I think I now understand the potential gains. The video in an earlier post demonstrates a possible range.

1st, I will break it in well.
Then, I will get a bore scope in their.
I will then go from there.
If necessary, I will up grade the barrel.

Thanks for all of your help. Some people just get lucky, that's not me. Maybe this time.

I wonder if the dealer would let the gunsmith look at it first. Does that seem like a reasonable request?
 
I've read all but positive things about tubbs final finish bullets and loaded ammo. I've read post and articles where new guns (cz550 and ruger77) had trouble or less than expected accuracy when they had a couple boxes of ammo through them (each grouped between 2.5 and 3" with good ammo). After a box of tubbs final finish they quieted down to average a little over an inch. I've also read many accounts and directly heard another, where high power shooters would use them when their groups began to open up from throat erosion. Their results were all uniformly great. A new sendero should already have a gorgeous bore though.
 
I have no personal experience with them, and don't plan to have.
I would not shoot abrasive coated bullets in a good barrel of mine.

The fire lapping test Rifle magazine did a few years ago, if I recall correctly, resulted in two guns shooting worse, and one shooting very slightly better.

rc
 
The problem with lapping a barrel that's already cut to length is it can increase the bore diameter more at the ends of the barrel where the abrasive is introduced. Barrel mfg's who lap match barrels do so before cutting to length to avoid this. There is a difference of opinion on what qualified lapping but to me it won't hurt anything to run JB bore cleaner 20 strokes before you shoot it. I do it with most of my rifles. I consider that cleaning not lapping.
 
I once knew an older guy who SWORE lapping a brand new barrel.
He was so full of B.S. anyway that he truly turned me off regarding his theories.
My opinion??
Don't bother.
 
Update

I shot the first 15 rounds through this gun today. Shot 220 hornady RN for break in. I cleaned after the first round, then every other, until the last five. I used Wipe Out to clean the barrel. If there is copper fouling, it turns blue. After running a patch through it, no blue. I have filled it up again, and will let it sit till tomorrow to see if it had much copper.

I didn't expect to have great accuracy of these first loads, but I expected better than MOA. I did not get MOA. I am hoping it has more to due with the bullet.
 
I have been using J-B Bore Cleaner for years. It works nicely, but I have also read of the J-B Bore Brite. Here are what is advertised about each product as advertised at Sinclair International:

http://www.sinclairintl.com/product/5171/Bore-Pastes

J-B Bore Cleaner
J-B Bore Cleaner gets caked-in powder residue and copper jacket fouling out of barrels. This paste is non-embedding, which means it doesn't get stuck in the pores of the barrel.
Click to expand...

http://www.sinclairintl.com/product/5173/Bore-Pastes

J-B Bore Brite
J-B Bore Brite is a micro-fine paste compound that works as both a cleaner and a final polish. Regular use gives your barrel a mirror-like finish that helps prevent build-up of copper and carbon fouling. J-B Bore Brite liquifies during use to quickly remove fouling and powder residue in rifle and handguns, and plastic deposits in shotgun bores. Regular use between strings minimizes accumulation of fouling to help maintain accuracy.
Click to expand...

Here is the advertisement in MidwayUSA for Tubbs:

Tubb Final Finish Bore Polishing System
The Tubb Final Finish Bore Polishing System is composed of a series of 50 bullets that are impregnated with 5 different progressively finer compounds. Enhances accuracy by polishing out bore imperfections. The smoother bore results in reduced fouling and less drag. Also makes the barrel much easier to clean. Removes no more than .0003" of metal from the bore and includes a reusable plastic case. This is not loaded ammunition. Reduced loads must be used when loading Final Finish Bullets. Bullets are made by Sierra. The grain weight of the bullets will be listed on the end of the package. Tubb recommends using the starting load listed in the Sierra reloading manual for that grain weight and bullet. Tubb also recommends not to go above the starting load for any reason.
Click to expand...

Do any of you have experience with the Bore Brite? Is is better than the regular bore cleaner? Specifically, does the "polishing-effect" improve accuracy? Problem, does it actually remove microscopic levels of steel each time? Any insights will be appreciated. My inclination is to stick with the Bore Cleaner when needed. By the way, the impregnated fire-lapping projectiles, do remove up to .0003" of steel from the barrel, or so they are advertised.

Geno
 
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Do any of you have experience with the Bore Brite?
Click to expand...
I've been using that for a few years. I have zero(1st hand) experience with JB Bore Paste,seemed too aggresive for my tastes, so I certainly can't compare the two.
As far as actual accuracy gains with Bore Brite, I can say that "peak" accuracy between cleanings has remained a bit longer in (most) of the rifles I've used it in. I can't say as a blanket statement that it improves accuracy, but can say that it has absolutely not hurt.
 
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