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View Full Version : Just an Idea Regarding Firelapping…



2ndAmendmentNut
07-06-2011, 08:22 PM
Not sure if this is a new idea, but….

What if I were to melt down a stick of lube and then mix in some polishing/firelapping compound. Then simply lube my boolits with the mixture and shoot. Any reason not to try it?

jandbn
07-06-2011, 08:34 PM
No reason not to, but it may take quite a few shots if you are trying to remove metal/constrictions. Doing so may polish the bore although the lands would "see" way more abrasive then the groves. The lapping compound should really be embedded in the outer diameter of the boolit and maybe some left over in the lube grove for good measure. I just lapped a stainless Ruger Bisley to remove a restriction at the barrel/frame and under the front sight and all said and done, it was close to 100 lapped bullets using Veral Smiths lapping compound before I called it good.

btroj
07-06-2011, 08:44 PM
You plan to run it thru a lubrisizer? It may well lead to lapping the size die too.
It would work, to an extent, for pan lubing if shot unsized.
I ink it I best to use the lapping compound undiluted. Better cutting action. It also is beneficial to get the grit imbedded in the bullet, not just on it.
Unlimitedly I suppose this is an area that might need some testing. Would be hard to make a clear judgement as a barrel can really only have a constriction lapped out once.

It won't hurt anything, might just take longer. Give it a shot and let us know?

Iron Mike Golf
07-06-2011, 10:42 PM
I recently finished firelapping my stainless Redhawk. I did not do a lot of rolling the bullets between steel plates. Maybe 10 times back and forth. I did make sure the lube grooves had plenty of grease/grit mix. Took me about 100 rds, which was what the Beartooth manual said to expect.

I used that same grit to open up my .431 sizing die to .432. I set my lubrisizer up to do push-through and simply packed the lube grooves of 4 bullets with the gritty grease (320 grit). I ran each through twice, then cleaned the dies, and sized a bullet. Miked it and repeated until I got to .4316. Then continued, using 600 grit compound, until I got to .432. Then polished with Flitz.

geargnasher
07-06-2011, 10:42 PM
Jandbn and Brad both make excellent points. Lapping grit does it's best work when carefully and painstakingly embedded in the driving bands. It takes about two or three minutes to completely embed the bands. The velocities of firelapping loads are low enough to not need lube anyway.

Gear

bhn22
07-07-2011, 09:35 PM
I just finished rolling the grit into my bullets to clean up my 686 barrels thread choke. I do 80 passes with each bullet. I start with 24 coarse grit bullets, then follow with 12 medium grit, and finish with 12 fine grit for stainless barrels. Stainless seems to be more abrasion resistant, and tougher measures are needed. The barrels come out gorgeous.

I don't believe that just adding abrasive will remove much metal, if any at all, since there's no firm foundation to allow the grit to cut the metal. You might get a light polish from it, but I don't feel it'd be anything significant.

geargnasher
07-07-2011, 11:21 PM
Oh, it cuts alright. Do before and after impact slugs. The throat erosion is measureable.

Gear

btroj
07-08-2011, 07:16 AM
Oh, it cuts alright. Do before and after impact slugs. The throat erosion is measureable.

Gear
Gear, are you speaking of fire lapping in general or just putting abrasive on a bullet without rolling it into the bullet? Just wondering if you and I have different reads on what BHn22 said. I though he meant just adding abrasive to the lube would do little cutting.

I go back to an earlier statement I made, this is a good tome for someone to try it. We really don't know, do we? I am not interested as I know the "normal" method of fire lapping works, is reasonably easy, and is pretty controllable. I just don't like fixing what isn't broke.

44man
07-08-2011, 08:39 AM
Fire lapping a revolver has always worried me. If the throats are already oversize I hate to fire lapping boolits through them.
Boolits must be the right hardness and shot just fast enough to clear the muzzle. I watch them go across my yard! :bigsmyl2:
I started to leave the boolit clean and using a "Q" tip, I applied some grit just past the forcing cone, nice even coat to the lands and grooves. It is a pain to remove the cylinder each time but it seemed to work fine. I hate to have grit build up in the cylinder and get on the bushing and pin.
Maybe a special tool to stick down the muzzle that will spray a fine film of grit at the right spot??? [smilie=s:
Only a few Rugers needed it. Every BFR only needed copper removed from factory testing to shoot lead perfectly.

mdi
07-08-2011, 12:23 PM
Anyone ever hand lap a barrel? That would eliminate cylinder and forcing cone cutting. BTW; I've read fire lapping properly was considered "excellerated wear" and not really removing/cutting metal.

Iron Mike Golf
07-08-2011, 03:05 PM
44man: The throats on my stainless Redhawk did not open much after 108 rounds of 320 grit Beartooth compound, followed by 12 rounds of Wheeler 600 grit compound. Before and after, the throats all pin gauged at .432. The difference is after firelapping, the gauges do move through the throats easier. So, the process did open them up a little. No idea what that means with a blued cylinder.

geargnasher: I did not carefully embed compound in my lapping bullets. Info in the Beartooth manual says to expect it to take 100 rounds or so for a Ruger stainless barrel, following that 2-3 minutes of embedding. So I expected it to take more rounds as I was doing a casual embedding. But, it took me about 100 rds. Lands are sharp. Both pin gauge and slug tell me the tightest area is at the muzzle. The area needing the most work was just in front of the forcing cone. Once that area gauged, I went to polishing grit. Seems to me like my method was as effective as the textbook method. I don't know and won't guess as to whether the amount of rolling needed is less than the book says, packing the lube groove with compound is as effective, or somewhere in between. Of course YMMV.

I did use nothing but finger-smeared compound to lap my sizer die from .431 to .432.

44man
07-08-2011, 03:18 PM
320 grit is mild. LBT grit is much courser. It is like valve lapping compound.
Yes, Ruger barrels are TOUGH. I still do not want to cut where not needed.

Iron Mike Golf
07-08-2011, 03:29 PM
I hear you 44man. I have to say my leading issue is all but gone. I need to shoot some more, but after 160 rounds, group size is not affected nor is there any lead in the bore that a wet patch of Hoppe's #9 and a few dry patches can't handle. I am real happy with how things turned out and feel that using 320 as the coarsest grit and checking things (gauge or slug the bore) after every cylinder is a low risk procedure on a stainless Ruger.

geargnasher
07-08-2011, 07:41 PM
Gear, are you speaking of fire lapping in general or just putting abrasive on a bullet without rolling it into the bullet? Just wondering if you and I have different reads on what BHn22 said. I though he meant just adding abrasive to the lube would do little cutting.

I go back to an earlier statement I made, this is a good tome for someone to try it. We really don't know, do we? I am not interested as I know the "normal" method of fire lapping works, is reasonably easy, and is pretty controllable. I just don't like fixing what isn't broke.

I think you have it right, Brad. I reread Bhn22's second paragraph again and I think he was referring to the op's query about adding grit to the lube. I took what he said about rolling boolits out of that thing you call "context" :grin:, assuming the second paragraph was in reference to the first.

I can assure everyone that embedded boolits will wear the throat slightly, and also taper the barrel. I don't know that it will do it every time, but I'm two-for-two with rifles in this regard, the difference in before-and-after chamber/throat slugs is measureable, and seating\-to-engrave depth changed about .030" on one of them.

Gear

Gear