Fire lapping


PDA






X-Men
January 11, 2009, 11:23 PM
Does anyone have any experiance with fire lapping a barrel. I have a rifle that copper fouls very heavy and was thinking of trying David Tubbs Final Finish on it. The kit comes with 50 bullets with 10 each of progressivly finer compounds on them. Has anyone tryed them? Did you notice reduced fouling, improved acuracy? Anyone have any bad experiance with this? Any other tips you might have to reduce copper fouling?

If you enjoyed reading about "Fire lapping" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
rcmodel
January 12, 2009, 01:02 PM
The only thing I know about it is several years ago, Rifle Magazine, I think, tested it on two or three rifles. As I recall, one was brand new, one was an old mil-sup, and I forget what the other one was.

Bottom line was the new rifle shot worse, the mil-sup didn't change much if at all, and the other one suffered about 50% accuracy loss.

If I was you, I would forget the fire-lapping.

Get yourself a couple jars of JB Bore Paste, and JB Bore-Bright, and work your barrel over with that and cleaning patches, following the directions.

http://www.brownells.com/aspx/NS/store/catsearch.aspx?k=jb&ps=10&si=True

I know you can't hurt the barrel with it in less then a days work, and I know it will reduce jacket fouling.

rcmodel

Jim K
January 12, 2009, 03:16 PM
The electric bore cleaners work well and save a lot of effort.

Still, if the bore is really rough, fire lapping will help smooth it out. It is not guaranteed to improve accuracy.

Jim

MutinousDoug
January 13, 2009, 02:14 PM
I used the Tubb system on a Swede M38 and a S&W 66.
The Swede's throat grew a few thou longer and the barrel looked shiney but I noticed no improvement in accuracy or lessening of subsequent copper fouling.
The S&W was choked a little bit where the barrel goes through the frame (this is a 66-3 with no barrel pin) and Final Finish helped smooth that out a lot but again, no discernible improvement in accuracy. 99% of the rounds through this gun are mid-range wadcutters and leading, which had never been an issue, was helped slightly.
Over all, I was disappointed in the results.

moooose102
January 16, 2009, 09:54 PM
i used the final finish system on my marlin 1895g 45/70. the barrel was very rough and copper fouled like crazy. i would have to spend hours cleaning it after shooting (usually, i shoot between 2 and 4 boxes at a time). the original bore looked like the tooling was dull, or they speeded up the feed rate to high. anyway, after fireing the first 10, i could see it starting to make a difference. when i was done ( make sure you do the cleaning like you are supposed to!) it was MUCH smoother! way less effort to clean. the accuracy is slightly better (definitly measurable) but i did not do a velocity test, so i can not comment on that aspect. IMO, YES it DOES work, and quite well. when it gets warm again, i am going to do it to a couple of more guns i have.

krs
January 17, 2009, 12:33 PM
I'd go look around in http://benchrest.com/forums/
to find any info about it. If it works those guys will know, and if it doesn't, or if it does harm, they'll know that too and why.

Oro
January 17, 2009, 01:13 PM
When I was looking last year to buy a SOCOM 16, I found an article where one gunwriter tried to make his SOCOM 16 a MOA gun. The biggest change was produced by firelapping the gun with that kit - best "bang for buck" in the test.

The methodology was to take a box-stock SOCOM-16, determine it's best bench rest accuracy and ammo, then slowly make one change at a time and note the accuracy improvement. The best performance with any match ammo was about 4 MOA. The firelapping reduced that my about 1 MOA, glass bedding, trigger work, and bolt lapping and polishing all produced very incremental changes. The end results was $500 spent in accurizing and a 1.2 MOA gun. 1/2 the results obtained were by the $60 or so spent on the fire lapping kit.

Needless to say, when I learned that $1600 was going to guarantee me no better than a 4 MOA gun, I looked elsewhere. But the fire lapping results, and especially the results for the cost, were quite impressive.

.38 Special
January 17, 2009, 06:29 PM
I have not used the Tubb system. I have used the NECO kit, which amounts to the same thing, AFAIK. Results have been mixed. I have seen reduced fouling from some guns. Accuracy is usually not affected one way or another, except on revolvers. I do believe the ability to make precise and repeatable measurements is quite important when firelapping. Going into it blind is probably a poor plan.

highlander 5
January 18, 2009, 12:50 AM
I have used the bore lap compound from LBT and have had good results. I used it on my Ruger revolvers as the bores were quite rough and where the barrel was screwed into the frame was .0015 smaller than the actual bore size. used bullets cast from wheel weights and a small powder charge it took about 75-100 rds but it was worth it. My Ruger Bisley's bore is like glass,before fire lapping it leaded badly. Accuracy is about the same though.

stalkingbear
January 18, 2009, 06:56 PM
I CANNOT recommend fire lapping at all!!! I've had to change 2 rifle barrels for people that tried it and resulted in having new barrel. Needless to say, they didn't try to fire lap the new barrels. Fire lapping is merely a poor alternative shortcut for people too lazy to hand lap their barrel. It's MUCH better to take the time required and hand lap your barrel. When hand lapping, it's possible to feel tight spots or rough spots.

X-Men
January 21, 2009, 12:55 PM
Thanks for all the info. Looks like mixed reviews. Think I will try the JB bore paste first.

moooose102
January 21, 2009, 01:35 PM
stalkingbear, you may be right about the handlapping being better that firelappng. IF it is done by someone who truely knows what they are doing. but for average joe, who is not a gunsmith with this type of experience, we could screw up a barrel much faster trying to hand lap it. at least with a firelap kit, the bullet moves in one continual direction, with even and straight "strokes" if you will. now, turm loose a novice with a cleaning rod and some abrasive compound and see how even the barrel turns out. i really can not imagine it would be good, if it was even useable afterwards. i do not know what happened to the barrels you had to change out for customers. but for me, this worked quite well. i cant even imagine what it would cost to have a competent gunsmith lap a production barrel, or how it would turn out. do you normally have to cut the muzzel end off from a barrel and recrown it after you lap them? i read that someplace, because supposedly the ends of the barrel flare outward in a funnel shape. and there is no one near where i live that does that kind of work, so i do not know.

.38 Special
January 21, 2009, 09:42 PM
I'd be interested in hearing about why the barrels needed to be replaced, and how they were damaged by fire lapping.

MifflinKid
January 22, 2009, 12:57 AM
I used the NECO kit to fire lap two stainless steel Ruger Vaqueros with 5.5" barrels. Both had significant frame chokes: one at .4501 the other at .4502. The barrels alway leaded up from just beyond the frame to about mid barrel.

Following NECO's instructions I prepared soft cast bullets (BHN 10) with the bullet lube removed. The bullets were standard RNFPs at .452 but seated to 1.525" over 3.5gr of Red Dot. I wiped the grit off of the bullets and the cases -- it got all over the place.

I spent most of one day at the range doing the firing, cleaning and measuring cycle. (I really cleaned, right down to the bare metal using up a big can of Gun Scrubber.) I fired the rounds into white paper to make sure the bullets cleared the barrels. I did change my procedure for the second gun in that I would fire 12 rounds between cleanings instead of just 6.

My records show I used 46 of the 220 grit bullets on the firest gun; 50 on the other to get the frame choked areas to .4509". I finished with the finer grit bullets opening those frame choked areas to .451" and .4511".

Accuracy improved to 2.5" on gun #1 (from 3.5") and to 2.63" on gun #2 (from 3.25"). All at 25 yds from a bench rest. Barrel clean up is now much faster as they are bright and shiny.

Fire lapping seemed to work for my two guns doing it this way.

If you enjoyed reading about "Fire lapping" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!