Hand lapping a barrel?

[billy_56081]

Could someone please explain to me how to hand lap my Savage 110 barrel. I do not have the barrel on the gun and probably won't put it on for awhile. Will it be worth it to hand lap it. I think it would be a project I could do while sitting around the house.

[Mikey]

One way to hand lap a barrel is to pull a fine grit embedded, tight fitting (really tight fitting)  cleaning patch through the bore a number of times.  Try and pull through completely with one stroke rather than shorter multiple strokes.  Continue with this process until the barrel gets warm to the touch.  You should clean the barrel after each patch. 

I think handlapping is similar to polishing - it may smooth things out a bit inside the tube but I do not believe it has the same overall end result as firelapping, which is using soft cast bullets imbedded with lapping compound (check Veral Smith's website for what to use) travelling so slow that they barely make it out the barrel.  The purpose of the lapping process is to remove bore restrictions, roughness and irregularities left by the factory machining processes.  This is much easier to accomplish with firelapping and more effective than handlapping.  HTH.  Mikey.

[billy_56081]

I have firelapped a barrel before but was under the impression that hand lapping produced better results.

[iiranger]

Many years ago the Rifleman did an article on lapping. First you decide the "lapping material." REMEMBER, it is all "barrel WEAR!" Under close examination, even JB will round the edges of the rifling eventually. You plugged the barrel with a tight patch, poured molten lead in. Let it cool/harden. Shoved it out. Coated with grit of your choice. And using a rod... brass rod is good... shove it thru until it gets tired, worn, loose... Then you recast and do it some more...
Harvey Donaldson wrote of cleaning/polishing black powder barrels (softer steels) with toothpaste. He failed to mention a brand... The Rifleman article mentioned "valve polishing compound" like for re seating auto valves. 200? 400? 600? 1200? Then there is the "jeweler's rouge" they polish glass with, did anyway. Bon Ami is supposed to be mild.

Bottom line, i). shooting bullets will polish the barrel and I think that is more fun... & ii). the Rifleman procedure was for trying to save surplus military barrels that were "NRA moonscape" surfaces. I think NECO, pioneers in the use of moly, also sell kits for fire lapping. No reason you couldn't adapt the technology and use a rod...   You might want to visit benchrest.com and read the thoughts of the makers of top quality barrels. Many will lap the bore before rifling. Did when it was cut rifling anyway. luck

[benchracer]

There is an excellent discussion of this subject on the NEF/H&R forum under FAQ's.  There, someone has posted an article from Rifleshooter magazine that has step by step instructions on hand lapping a barrel.  I have a 22-250 that I just built on a mauser action with an Adams & Bennett barrel that looks like it could definitely benefit from hand lapping.  I intend to try it this week.

[gunnut69]

You can't lap a barrel with patches and fire lapping is an entirely different process. Lapping a barrel is best done with a steel rod, not brass. Remember that when two metal surfaces come together with grit in between, the softer material will embed the grit and cut away the harder.. Use a one piece steel rod, drill rod is just fine. It needs a free turning handle to allow easy following of the rifling. Insert the rod with notches filed into the end into the barrel from the breach end with a string tied around the rod about 4-5 inches from its tip. Push until the rod is nearly at the muzzle end of the barrel. The string must seal the bore. Lightly heat the barrel end and pore in molten lead. After the lap has cooled push it part way out of the bore. Never remove the lap from the bore as getting it re-indexed is nearly impossible. taper the end of the lap protruding and lube the lap. Charge it with the lapping grit chosen. I would suggest polish to be a place to start. Pull the lap the length of the bore, already lubed of course and allow a bit to protrude from the rear. usually the chamber will preclude any additional work be done on the lap from this end as we don't want to allow it to completely exit the bore. Long even strokes thru the bore will polish. If tight spots are noted they can be given special attention. Generally speaking this is not a process for an amateur and even a skilled smith can get into trouble quickly.. I would never use grit under 800-1000 grit, and that only in badly damaged bores. To smooth a newer bore the finest polish available is adviseable. This is not a how to but a brief over view to give an idea of what is involved.  This is NOT something the average guy might do some evening while sitting around the house.

[benchracer]

Well, it would appear that there is fairly broad disagreement on the correct or best way to lap a rifle bore.  So, billy 56081, could you clarify what your objective in lapping is?  Are you trying to restore a damaged bore? Are you trying to reduce fouling? Improve accuracy?  I have thought about firelapping, and agree that it sounds like more fun.  However, I can perform the procedure from the NEF forum with materials already on hand and perhaps learn something in the process.  I see that a couple of people have suggested forming a lap out of lead, which would seem to be a very precise method of doing this.  However, it seems like such an involved and "pros only" approach would only be necessary if one were trying to restore a damaged bore or if one was doing something in preparation for benchrest shooting.  gunnut69, I am confused by your assertion that "You can't lap a barrel with patches...".  Are you saying that an abrasive treated patch will not remove metal from the bore or are you voicing your opinion that the patch method would not produce satisfactory results?  Or did I miss your point completely?  If I perform the hand lapping task according to the patch method instructions, am I just wasting my time or am I taking a more serious risk than that?  Some elaboration on the subject would be helpful, at least to me.

[billy_56081]

I am just figuring on smoothing a new barrel up for easier cleaning.

[quickdtoo]

Billy,

JB Bore Bright, JB non-embedding compound, Flitz, Maas, Simichrome or any fine metal polish will accomplish that goal, I've done it on many, many barrels. Just use a tight patch on a jag on a rod with a rotating handle so it can follow the rifling, make full strokes one way, breech to muzzle and out being careful to not over stroke letting the rod wear the bore on exit. Change the patch often. Keep the rod clean and use a bore guide on stiff enough rod to make sure the rod doesn't flex and touch the throat.

I gave this treatment to my 338-06 Ultra that Wayne York cut for me from a 25-06, he was impressed at how the bore looked after the treatment.

Try it, you'll like it.

Tim

https://www.brownells.com/aspx/ns/store/ProductDetail.aspx?p=1161&title=J-B%7e+BORE+BRIGHT

[gunnut69]

Patches don't apply even pressure in the bore. They work unevenly and that produces uneven work. It won't likely damage the bore as fire lapping can but it won't improve it's performance much either. Felt pellets may be a better choice but to smooth a bore and polish it a lead lap cast in place is the choice. I've seen the patch scenario before and it's likely that simply firing and cleaning the bore as needed would do as well and be a lot more fun. If you wonder why the patches aren't the best way ask yourself how many ways that patch could be folded and what would the effect on the bore be if each patch was different(as they would surely be).

[Devy55]

Regarding the unevenness of the patches, would a cotton bore brush be more appropriate?  It's more uniform and symmetric.  If coated with a polishing compound, shouldn't it produce a more consistent and even lap?

[gunnut69]

Perhaps but the basic problem is the shape of a rifle bore. The most pressure would be applied to the tops of the lands where it is usually least needed. The least pressure would be applied to the corners of the groove, where it's usually most needed.. Also as the mop is pulled or pushed the resistance would change as the material the mop is made from flexes. Lead laps will push harder of the tight spots and slide more easily over the loose ones. This will tend to equalize the dimensions, a recipe for better shooting.. it will also help eliminate those trouble spots in a bore that want to collect jacket fouling. Shooting and cleaning will polish a bore and are far more enjoyable that casting a lap. But if needed a lead lap is the best way to address the bad bore. Not the only way, just the best.

[Devy55]

If I shoot and clean, what ammo is best?  I understand there is special ammo designed for fire lapping.  Where can I find them?

Thanks.

[gunnut69]

I was suggesting that you simply practice with whatever ammo you normally shoot. Normal shooting, and cleaning as needed, will put add wear to the bore and will smooth any rough spots out.. Fire lapping is a fairly drastic procedure that I don't recommend for any but the worst case bores. It adds a lot of wear to the throat and I don't believe it is necessary in most cases. Fire lapping supplies are however available from Brownells and other shooting suppliers.

[DDelle338]

    I've Fire Lapped two rifles, both would copper foul so bad that I had to spend two days cleaning between each shot and still not get all the copper out. The first rifle was a .338 Win Mag. and the second was a .243. After doing the fire lapping to the .338 which took about a week for me to do, I cleaned it real good and went to the range, shot two rounds to season the barrel. Then I shot my first group and I was pretty happy with myself for being such a LUCKY shot, as all 5 holes were touching. Then I shot another, and another. I shot some groups that looked like a .338 bullet lying on its side! Da*m tight! I was happier than that proverbial pig. But it still copper fouls. Not as bad, but still requires allot of cleaning. But I can't complain because of what it did for the accuracy.
  Then I decided to make that .243 shoot one hole 5 shot groups also. I did the fire lapping on it. Helped the fouling some, didn't improve the accuracy that much. And now after doing the lapping the throat is soooo long that I can't get close to the lands with any bullet, even a 100 gr bullet seated way out in the end of the case doesn't touch them. Now this gun still shoots pretty darn good. Sub moa, sometimes I get al 5 shot holes touching. But I know that I severely shortened this barrel's life by doing the lapping. And I was pretty conservative with the lapping procedure.
  So....  Why do you want to do it? What do you want to gain? Can you put up with a little more cleaning than you like? What cal. is the rifle? What do use it for? How often will you need to clean it? All questions you need to answer for yourself. Then decide which route you want to go. All lapping is wear on the barrel. I think that if you have a problem in the bore, i.e. rough spot, then hand lapping will be of more help because you can concentrate on that spot. If it's a fouler, and you can't keep up with the cleaning, then go ahead and fire lap her. But I suggest you start conservatively, watch that throat, especially if your talking about the small calibers.

[Tom H.]

The most difficult lapping job that I have done was on German cape gun with a dented barrel (the rifle barrel )  my guess is the dent was about .005 or so. The muzzle was somewhat hogged and there was a tight spot about half way down.

Basket case.

Made a lead lap  about 2".

I coated the bore with a fine layer of 600 grit (really bad bore) and oil.  Make sure that the layer is fine because it is possible to get the lap bound in the barrel.  As you try to push it out, it will swage and become stuck. and that grit might as well be cement.

Use two steel cleaning rods with a muzzle guide on each.

Drive the slug from end to and for a short time. Add grit if you have to.  Cast a new slug if needed. You'll be able to tell. Change grits until you get down to fine stuff like 1200+

Then drive it within an inch or so of the muzzle for a long enough time to create a slightly choked area. Believe me, it probably only amounts to .001 or a fraction thereof but I have found it to increase accuracy.

The rifle that would shoot into 6" at 25 yards now shoots into 1.5" at 100.

If the slug gets stuck:  Purchase an inexpensive Kleen Bore steel takedown rod.  Go and find a drill that is slightly oversized for the threaded area and drive it in. You now have a 24" drill. Make sure that is is in straight
Send a rod down with a pointed brass jag and center punch the lap.
Drill the lap by hand.
When it has a hole drilled through it, pressure should be released and you should be able to drive it out.

Hopefully that won't happen

This is the way that worked for me. 

Good luck.

Tom

[gunnut69]

I find that drilling the hole before needing it can help. It is best done initially when the lap is pushed from the bore for trim and charging. Just drill 2/3's of the way thru.. I've not tried 2 rods but it sounds like a normal job otherwise.. It's not a walk in the park but it can certainly help. Some small grooves in the lap can also help avoid jamming by acting as reservoirs for the abrasive material.. And to emphasize again 'lube the lap or it will stick!!'