Has anyone had any experinces with fire lapping a barrel?  If so, what were your results.

I'm with Joe on that but, I used to shoot with the CBA guys back in the late 80's and early 90's and at that time, some of the guys that did very well fire lapped. I've never tried it but, I have hand lapped 2 muzzle loader barrels. It is a lot of work. 

Try the CBA site and ask, maybe there still using that method. As i remember, it was mostly to smooth out the throat and you really don't need that with breech seating unless there is something wrong with it.

Frank

Yes, just did it to a Favorite dating from 1896 to 1901 a few wks ago.
Lowdown is it worked pretty well;
Barrel was badly pitted when I got the rifle (a gift to my son actually from his father in law) --so bad that after 5 rounds bullets would keyhole at 25 yds, and strings of lead would come out of the barrel when trying to push a patch through.  Groups, more like patterns, were 5 shots in about 10" and about 8 were still on the paper at 25 yards by the 10th shot it was off the paper.
I tried bronze brushes and Hoppes, then Big 45 Frontier cleaner, then JB bore paste many times (quite a few hours worth all told).  This stopped the lead strings from forming especially in the rusty ring area about 8" in front of the chamber.  Gun would now keep 10 shots on paper, but still keyholed after about 7 to 10 shots
Then had a friend who had just tried firelapping  a few wks earlier and had some 400 grit clover compound (from an autoparts store) who gave me some.
We did 10 rounds smeared on lead bullets, then clean and repeat for 30 rounds total.
Gun is better--will now put 5 rounds in 4", 10 rounds in about 8" at 25 yards, and no lead strings in the bore. Bore is still mostly dark, can't see any rust though.  Just starting to shine a bit when clean and then oiled with a patch.
Going to try another 20 rounds in a week or so to see if I can improve it.  It'll never be a tack driver and most likely we'll have it relined, but I still want to see how good more fire lapping can make it.  No risk of ruining the bore here--it was about as bad as a bore could be and still see most of the rifling.
I'd say give it a shot so to speak.
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Hope this helps

If you are talking an old barrel that needs help, fire-lapping 'might' be a good thing. Having had three rifles rebarreled in the last year I've had an opportunity to talk with several of the major mfgrs (Shilen, Kreiger, Douglas, etc.). Every one of them has stated uncategorically that "fire lapping would void any and all warranty on our barrels..........". I'm taking that as a strong "no" vote on fire-lapping a new barrel.

I guess I should have said why I was thinking of fire lapping.  I have an older Shiloh sharps, sporter #1 , 45-70, 30" half round/half oct.  It is a big timber rifle while Wolfgang was still there.  Love the gun and great time with it.  It has just never grouped like I thought it should.  I took it to a gunsmith with thoughts of replacing the barrel.  The gunsmith said let him scope it and look at it first.  With the bore scope he said it looked great.  He could only see one little spot and said that shouldn't bother anything.  He then used pin guages to run down the barrel. A .450 pin would go through the complete length of the barrel.  However, with a .451 the pin stopped about where the barrel started going round from the oct. part.  I had been shooting a bullet through 
the back part at .450 and expecting it to continue down the barrel with a good twist after it opened up to .451.  If it had been in reverse of that, (open to tighter) I would have been ok.   This is when he said he had good luck with fire lapping to increase the back part of the barrel.  I did try it last Saturday with some gain in the tight spot of the barrel.  I can now get the .451 down the whole length of the barrel.  I am going to do it again as soon as I get to the range again.  I had gotten the fire lapping kit from Midway.  It has 220, 320 and 600 grit polishing compound.  My first try was with ten 220, five 320 and five 600.  I also shot 10 rounds of regular black powder loads.  My goal is to get closer in the back in to .452 with the front of the barrel .451.  I will report on the results.