David Tubb's "Final Finish" Fire Lapping System

[03lover]

Has anyone had experience with the Final Finish System, fire lapping system marketed by David Tubb?

I tried it in a 357 Magnum revolver that had a bore constriction where the barrel screws into the frame and the bore had a leading problem. This lapping system was recommended.

Well, I was surprised to see the lapping bullets were jacketed soft points and not lead. I was
also surprised the loads recommended were stated in the instructions to be most any starting load in the manuals.

I followed the instructions to the letter and when I completed the lapping and gave the revolver a complete cleaning I proceded to test some of the cast loads I had had some minor leading problems with prior to the lapping.

After only ten rounds had been fired, I had leading in the forcing cone and throat that looked like someone had just soldered the first inch or so of the bore. Solid lead, not the little bit that I had before after 40 to 50 rounds.

I think David Tubb's "Final Finish System" of bore lapping has ruined my barrel by opening up the forcing cone and throat of my 357 magnum to a point that I now have some serious hot gas by-passing the bullets and flame cutting large quantities lead onto the bore.

I emailed David Tubb and got no answer. He must want my money, but doesn't want to get involved is helping to resolve the problem his lapping system has caused for me.

I don't recommend anyone use this product for fear of ruining a fine firearm.

[jack19512]

After only ten rounds had been fired, I had leading in the forcing cone and throat that looked like someone had just soldered the first inch or so of the bore. Solid lead, not the little bit that I had before after 40 to 50 rounds.

I think David Tubb's "Final Finish System" of bore lapping has ruined my barrel by opening up the forcing cone and throat of my 357 magnum to a point that I now have some serious hot gas by-passing the bullets and flame cutting large quantities lead onto the bore.







I don't know it all for sure but I don't think that is your problem.

[anachronism]

Did you slug the barrel before & after the lapping? I've lapped a few barrels & have never had an issue, and I've run more than simply 10 lapping bullets through the bores.

[Wally]

anachronism,

I have a SS Ruger Blackhawk .357 Magnum revolver that leads up in the first inch of the barrel probably due to an obstruction at the frame/barrel juncture. I'd like to fire lap and wondered what method you used. I have studied the Neco method and wondered if you used it or some other method.

Thanks...

[largom]

I presently have 17 kits of Tubb's firelapping bullets in various calibers. ALL FOR RIFLES. I have never lapped a revolver but I highly recommend this system for rifles.
Larry

[BABore]

I used the Tubbs bullets on a last resort 300 Win Mag. It does do a fine job of metal removal and polishing. The biggest problem is that most all of the metal is removed from the lands and the grooves are almost not touched. Also, because the hard jacket has springback, you won't achieve a tapered bore or work the bbl progressively. I only firelap bbl's now with the Beartooth or LBT method. 10-12 bhn boolits with a good bearing length. Embedded with 320 grit Clover brand lapping compound and fired at airgun velocities. Complete cleaning every 5 rounds. When the muzzle end of the bbl just shows the slightest sign of the tooling marks getting burnished, I stop. After a thorough cleaning, the bbl get 100 strokes, back and forth, of a old brush, wrapped in cotton cloth and coated with the same lapping compound. It should be a tight fit and warm the bbl when done right. Never had it fail to give great results in many revolvers and rifles. Unless a new gun purchase has a custom, hand lapped bbl, I don't even hesitate to firelap it immediately. My results are always that positive. I have heard that the Tubbs kit it better suited to touching up a worn, eroded throat, than a full out firelapping job.

[03lover]

I think the problem is with the jacketed bullets used in the Final Finish lapping system fired at higher velocities. The lapping systems like LBT uses soft lead bullets fired at very low velocity. The lead bullets will fill the bore, work on the grooves as well as the lands and provides a tapered bore that is desirable for handgun accuracy.

The second Final Finish lapping kit I had purchased went to the land fill. I wouldn't touch that type of lapping system with a ten foot pole, ever again.

[mike in co]

so what was the restriction dia before and after ?
what is the bbl dia after the restriction , before and after ?
what size is the boolit you used originally and after ?
how hard is the boolit, what is the lube ?
what velocitcy ??


mike in co



kinda hard to blame the kit......

[bearcove]

The Tubbs sys says lowest starting velocity I believe. I have a .300 Mag I'm going to do. I'm going to use a slow cast load and check for a clear bore before next shot. If you are using jacketed load data I think you might have too high vel.

[Angus]

Are your cylinder throats undersized like most Rugers I hear of (including my 41)? If they are, then fire lapping isn't going to accomplish anything since the bullet is undersized when it contacts the barrel.

[yondering]

You mis-used the product. The Tubb's system isn't intended to remove a bore constriction. It polishes the bore rather than remove significant metal with abrasive lapping compound. I seriously doubt you removed the bore constriction with what you did, certainly not to the point of causing leading.
It works very well in rifles.

[Char-Gar]

You leave out the inportant information such as which cast bullet, what alloy and what power charge? When I see sixguns with lots of leading in the first inch of the the barrel from the breech end, I don't think "constriction". I think an alloy that is too hard and a bevel base bullet.

Way, way to much is made of this contriction. I have some sixguns that look like a washboard in that area but do not lead and shoot very well. I have never "fire lapped" a sixgun as I have never felt the need. I have polished a bunch to take out the micro-burrs and that does yield a barrel that doesn't lead and is easy to clean.

Unless, I have a bunch more information, I think you are giving Mr. Tubb a bum rap.

[anachronism]

BABore described my method exactly. I got my lapping information from Marshall at Beartooth Bullets. It worked perfectly for me so I never tried anything different. I use soft wadcutters for my .357s & an old scratched up LEE 240 gr SWC for my 44s. LEEs old 44 SWC is really nothing but a wadcutter with a rudimentary nose on it, and it works perfectly for lapping. Rugers stainless steel is very abrasion resistant, and may require multiple treatments to achieve your goals. As always, lap a little bit, clean it & slug it to check your progress before continuing. This is something it's best not to overdo.

[dsmjon]

Why not use a product like Brownell's Borebright and some elbow grease?

[mike in co]

Why not use a product like Brownell's Borebright and some elbow grease?

cause is a polish, not a lapping compound

[Rich S]

my thoughts run toward the tight cylinder throats, if the bullet leaves the cylinder smaller than bore diameter gas will get by it in the bore. maybe slug the throats and if needed see if cylindersmith.com is still working their magic out in long island, he is well regarded over on the ruger forum.
Regards,
Rich