Lead Lapping of barrel

[5.56 123]

Hi - Maybe an old question but I haven't found an answer. I have tried to lap a barrel with a lead slug but always had the same problem. I plugged the barrel maybe 2 inches in the bore, poured molten lead around a metal rod with a thin plastic sleeve, pulled it out, and the plug, covered it with my 320 grit Clover compound, and started...but after no more than a couple of strokes the lap is too loose to do anything. I then tired wheel weight alloy-same thing. I tried pouring a 4 inch slug-same thing. I tried pouring a 4 inch slug of Cerrosafe and yes, same thing. I have read articles where the writer has said to stroke with 'a lead' slug a hundred times where I can't seem to get over two strokes out of one slug. Any help with this from anyone would be greatly appeciated. I can say how I solved the lapping problem with a couple of .45 barrel. I drilled a .452 hole in a .38 cal Lee Bullet Mold. I just poured 'some' lead in the hole-it is not too important how much...and then just rolled in the grit-I then did the same with some 500 grit. I have read where some have said that if the barrel is too smooth and shiny, it may lead-up. I have done this to two different .45 barrels and have seen no leading what-so-ever.
Thanks for any help an the hand lapping.

[stubshaft]

When you lap starts to get a little loose use a close fitting brass rod and upset the lap (hit the rod with a hammer while supporting the rod thereby expanding the lap). Soft lead works best as it will retain the grit and is easy to upset.

I've never seen a barrel that was too smooth. That is also the first time I've heard of that someone thought a very smooth barrel would "lead up".

[btroj]

I do believe I have heard that the barrel makers don't go much beyond 320 grit or so because they find the fouling from j-word bullets increases. I know this sounds odd but when dedicated long range high-power shooters believe in it I am tempted to agree.
Don't know if this is true of lead but who knows? I do know I don't see many suggesting fire lapping with much finer than 320 grit and that is what I have used. Works very well for me.

[zuke]

If you start to paper patching for that rifle each shot fired will polish the bore.
I have an 1895 Marlin that is like a mirror, and that's before I run a cleaning patch thru it.

[5.56 123]

Hi stubshaft & btroj - Hey thanks, I'll try that..makes sense to me, just that I may be doing this a little too often. I was talking on the phone one day about this very thing years ago with the owner of a major barrel maker, I forget which, and he said that they didn't lap their barrels 'too much' - just enough to not lead-up. He did not want to give away any trade secrets but he said that he would guarantee 'his' barrels would not lead-up...and he would not tell me the finest grit that he used. Doesn't that sound somewhat strange? I will sell you a barrel but I will not tell you how smooth the bore is. I wonder just how something this important to firearm making is keep so secret. Now I have read where military bores have to be rough to a certain extent to save weight. The rationale being that the rough bore allows the pressure, thus a maximum velocity to be obtained without the requirement for a stronger receiver and bolt, etc. I can see this...with say a super smooth bore one would have to make a more stronger rifle to get the necessary presures to get the higher velocities. Now maybe this same idea carries over into the typical civilian firearm, I don't know. Could this be that simple? I do know that I was talking to a Nosler sales tech one day on the phone when they first came out with their Moly coated bullet and he would not sell me any of his Moly coated bullets until he informed me about not to expect the same velocity from the coated bullets and that I shouldn't just increase the powder charge to get the same velocity as a standard bullet because of the higher pressures required. Now this makes sense to me. A box of the Nosler Partition Gold, 180 grain, .308 Moly coated bullets are still setting here in front of me. To date I have not tried any Moly bullets.

zuke - I too have an original Marlin 1895 in .40-82 that I haven't gotten around to smoothing out the bore. Hey, it may be easier and less messy to soak some strong absorbing paper in a mixture of fine grit and water and let dry and paper patch the way to a fire lapped bore - I wonder if anyone has tried this?

Well thanks everyone...we'll keep trying at this end...

[pdawg_shooter]

If you start to paper patching for that rifle each shot fired will polish the bore.
I have an 1895 Marlin that is like a mirror, and that's before I run a cleaning patch thru it.

+1 on the paper patching. I cleaned up a SMLE bore that had reamer marls on top of the lands with around 200 PP bullets, no lapping compound used. The bore now looks like the best custom barrel and shoots great. Fouling cleans out without a brush, just one wet and a couple dry patches does the trick.

[stubshaft]

Most of the barrel lapping systems I have used http://www.google.com/url?sa=t&source=web&cd=1&sqi=2&ved=0CBYQFjAA&url=http%3A%2F%2Fwww.neconos.com%2Fdetails2.htm&ei=6WHITZOFNYrWtQPGvPmXAw&usg=AFQjCNEJsn3qU70Kb_TdX1dMrju5za66RQ&sig2=FhOOrwlyQ3tVnZtT1QaOcAgo well beyond the 320 grit mentioned.

Your comparison to having a rougher bore to increase velocities versus a smooth one is valid. But, increasing velocities and reducing fouling are two entirely different problems. I don't believe there is a competitive benchrest shooter either CF or smallbore that would compete with a barrel that had a 320 grit finish. I have examined bores from Shilen, Broughton, Lilja and many others whose bores have shined like mirrors.

Will a 320 grit barrel lead? Probably not if a hard enough alloy is used in conjunction with a good lube and that is sized properly.

Will a barrel finished with 1200 grit be easier to clean? Yes.

Will a barrel with a very smooth internal finish shoot better? Thousands of benchrest shooters and smallbore competitors seem to think so.

The decision is yours. One of the biggest advantages of hand lapping is that you remove high spots in the rifling, and that in itself will give you better accuracy.

[nanuk]

I had done some reading on lapping and one of the comments was a 'too smooth' barrel can cause copper fouling as the copper is a poor lubricant and can foul with the increased friction

Whereas the smoother the better for lead, as lead itself is a lubricant in itself, albeit minor.

they suggested trying to put a fine film of lube on J-words to see if it will reduce fouling in a mirror smooth bore.

I dunno, but I think a bore lapped mirror smooth will have a more true bore, and therefore be more accurate... perhaps I'm wrong....

[mold maker]

I have fire lapped 2 older military (06) rifles and improved the performance of both. 1200 grit final on both, and mirror like bores. I also found that a light lube reduced the copper wash deposited. No problems with leading at all.
The cleaning of both were much quicker/easier.
Would I do it again?? You bet ya. If I had another with a dark barrel, it would be lapped first thing. Just like my brass, I like it shiny.

[5.56 123]

Well I agree in a smooth barrel - this is why I would like to look into this some more. Lilja barrels was mentioned...the owner or coowner of Lilja is the one I was talking with that said that he didn't make his barrels 'too smooth' and wouldn't tell me his final finish grit size. A link to NECO was given - I had a nice long and informative conversation with the coowner of NECO years ago. I have a few old surplus barrels to try on and I will do something even if it is wrong but I don't see how I can mess things up at all. I saw this link about paper patching and mold making I thought was interesting, especially for the onetime special bullet mold - a more simpler way to make one. Well...my 'linker' is not working, sorry. It was the first one that showed up after googling, "How to make a paper patched bullet."
And...and...Mold Maker - what a pleasent surprise.

[Molly]

I've had excellent results using half a normal powder load and JB compound with jacketed bullets. The bores look like they've been coated with mercury, but aren't enlarged. I wrote it up in a thread called 'fire polishing' if you're interested. It's worked for a lot of folks.

[B R Shooter]

I think most barrel makers don't lap finer than a 320 finish. And really, that's pretty good. All of the marks in a barrel after lapping are all in the ling direction, bullet travel direction. No chatter marks are left. Plus, when get down to the real finer barrels, they won't lap a barrel until the barrel has been turned to final contour. Then they can feel any variances on the ID. I knew a barrel maker quite well that said he could feel .0001" while lapping. His barrels shot very well, so I can't argue that.

The problem with fire lapping is the throat gets lapped away more than the rest of the barrel.

[Bent Ramrod]

Don't worry about the way the lap feels. It is still cutting as you push and pull it back and forth. Feel for slightly tight or rough spots in the barrel and give them extra local stroking and then pull/push the overall length for five to ten strokes. After maybe 50 or so overall strokes remove the lap, clean the barrel and slug or shoot it to see if smoothness or accuracy is better. Then cast the next lap if it is indicated and coat and lap some more. It's very much a "cut and try" process in my experience.

If you upset the slug in the muzzle, you run the risk of enlarging the bore at the muzzle. You want a choke there, if anything, rather than the reverse.

[5.56 123]

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Hi - I read everything I could find on Molly's thread of 'fire polishing' and the controversy of the 'snake type' polisher and the longer, harder lap where the difference is lapping to get some order of unifomity to the bore and just polishing for a 'shiny' bore. These are two different things and I thought what would I do if I was selling barrels. A professional major barrel maker may not be trying to get the best barrel on the market-it is like the perfect golf score...you can't get there from here. So...he settles for something that looks good, works good and tries to put the minimum amount of time in. He has no idea what-so-ever what the user is going to be able to do with it as far as accuracy is concerned. He can say that most of my other customers are getting things like, 'groups of 1/2 inch or less'. As most of us know, if a shooter pays $800 or more for a barrel, he has a pretty good idea of how to pursue that half inch group. So...if a person with just lots of money get one of these $800 barrels and shoots nothing but over the counter ammo, he most likely won't get there. What I am saying is that I think most major barrel makers have settled in a comfortable routine, cinched down the blinders and crank them out. They have developed a quick way to lap and polish their barrels. After reading Molly's 'fire polishing', I realized that the typical barrel maker is not saying, "Lead Hand Lapped barrels." He is saying, we 'Hand lap our barrels'. This can mean anything. Somewhere along the line this 'lead lapping' idea got over blown, I think. Here I am trying to use lead to lap a barrel and now I can think of a dozen other ways to do it easier and quicker...I think. Hey, I am not the professional barrel maker, just a hacker that is not afraid to experiment. If my quick and easy method works, I'll be trying it on two of those new Savages in .308 and .22-250 that I bought. A few years ago right after I bought them I had a chance to talk to a Savage design engineer at the Savage booth at a Shot Show in Las Vegas. And boy, what he had to say about them was an eye opener in 'their' firearm design. Basically he told me that the main criteria of the whole project was to make it 'cheap' with some new ideas and while following some basic firearm criteria and the resulting accuracy was just a lucky plus. He didn't tell me this but I can see where they didn't even want to spend 5 or 10 minutes to polish the bore. The reason I say 5 or 10 minutes, I took a barrel from a 98 year old Colt 1911 with a s/n 20 thousand and some that I have that had a bore that looked like the typical 98 year old brown/grey bore and took a bronze bore brush and wrapped a pieice of tee shirt around it, squirted some 3 in 1 on it and sprinkled it with some 0.3 micron (that is maybe 30,000 grit) aluminum oxide and after ten strokes or so it looked as shiny as can be. I don't think that this in any way wore too much metal away. I have a neighbor that would think that this is heresy. I have seen this all of my life where the firearms are for sale in a pawn shop with dirty and black bores. I could never figure this out where the first thing anyone does is look down the barrel. I aways thought of the leade or throat being hit with that new charge of grit when fire lapping. I don't know if they still do this or not but years ago the typical .22 Rimfires came with a tighter 'target' chamber or a 'sports' chamber. I always assumed that this was so the sports chamber could better take the varitity of different ammunition where the target chamber could not.
Back to the 'fire polishing' issue versus fire lapping...of course the typical barrel maker does neither. I think they may spent 10 or 15 minutes for both - I don't know.
Let me skip to 'dry lead bunishing'...this may help someone. A few years ago I bought three of the .22 Mossberg Model 44 US rifles through the CMP and when I got them I thought 'what was going on', I couldn't fgure out the two inch groups at 50 feet. Yes, I was using the typical cheap .22 ammo, but this was not right. I cleaned the barrels again - same thing. Then I read on a forum where some of these rifles were made with a contractual stipulation that the bores be, "Dry lead lapped.". Someone in the US Army procurement department had the bright idea that since a typical .22 gets more accurate as it is shot, they will just order theirs lapped with dry lead and skip this natural breaking (wearing) in process. That is why they looked so new - they were just set aside as defective...as they were. I then scrubbed the dickens out the barrels with a bronze bore brush and got what I hoped was all of the lead out...and then it shot its normal half to quarter inch groups at 50 feet with the Lyman peep sights. I just know that there are a lot of those out there with those leaded bores with perpexed shooters.
Hey, I have used up more than my share of bandwidth and your time - sorry.
I am going to try some quicky lapping ideas......

[B R Shooter]

Well, the top shelf makers all hand lap their barrels. And all of them use a poured lead lap. There is only one way to lap a barrel properly, and that is to pour a lead lap FOR EACH BARREL. The premium makers guarantee .0001" uniformity end to end. You don't get that cutting corners. They are air gauged or other means to keep their reputation intact. I could write a list of makers that maintain this level of quality, but I'm sure most know who they are.

One quick way to check a barrel for uniformity is to use the bushings you have for your piloted reamers. Start with the smallest of course, then slowly push the bushing through feeling as you go. Step up one size and repeat. You'll know when you "feel" you're at the right size, and can tell if there are any tight or loose spots. Making a pure lead slug and doing the same thing can be done as well, and actually is a better way since you will be feeling the grooves as well as the lands.

I did this once on a barrel from one of the most famous makers in this country, and found a tight spot. I used the rod, marked the outside of the barrel of where the tight spot was and what size bushings I felt it with. I got a phone call very promptly, was told I was correct, and had a new barrel delivered quickly. That's the service you get form the people that stand behind their work, and care that their barrels are as good as they can be. I have heard of some stories of how some makers "lap" their barrels, and it is not pretty. But it's hearsay, not first hand info so it won't be told.

[5.56 123]

Hi - I think that these internet forums and Google are maybe the best thing for new ideas and information that has come along since the printing press with ideas and opinions which will cover the gamut and revisiting old areas still bring out new ideas. If I wasn't having fun shooting and looking forward to new challenges you wouldn't find me here. And maybe this is why one won't find the barrel maker here. They are operating a business and maybe it is not 'fun' for them...or they may be thinking, hey, I know all I need to know, just let them play. Either way it is still fun for me and one doesn't have time for everything so we have to sorta filter out some things. Let me list some things that I have thought about and have some opinions about:
1. Maybe the quality of the barrel is not the most important thing with precision shooting - maybe it is just that the barrel makers would like you believe this. I think that maybe this area has reached what is called the, "Law of diminishing returns." That is to say a good shooter with the right ammo may be able to shoot just as good with a barrel that is not as good as the best available. And most important, one can possible take the best barrel that money can buy and shoot some random over the counter ammo along with some cheapy rifle and not really know which will shoot better.
2. Maybe the more important things are using more uniform bullets and getting more near the same pressure behind each bullet fired, of course after getting that good working powder charge. Maybe the barrel is not the weakest link.
3. But I find the easiest things to 'fiddle' with are things that we have more control over. The thing that keeps coming to my mind as 'possible' having the most effect on repeatability is pressure. I know, the barrel can be a major part of this. This is why I have cut granules of powder in two to try and get the same weight in the case especially with the smaller cases. I know that there are those that say, "This is over kill and a waste of time." But I have the luxury of having a bench rest 50 feet from my back door...and remember it is not 'work', it is fun. And...I think that I learn something from each shot. I can work up a good load for a given bullet, etc., and for example just vary the powder charge one tenth of grain and the group goes to pot...and this happens in my little .218 Bee. Making a more uniform burning powder is beyond me...I think the powder gods are saying, hey, just use what we give you and be happy...don't worry about the small stuff. Another thing that I have experimented with in trying to get close to the same pressure is using one of these non contact thermometers and a stop watch. Get the barrel warm at the receiver, let it cool down to a certain temperature before the next shot. The stop watch is just to try to get the time of the cartridge in the chamber closer to the same amount of time.
4. Along this same line, I can not figure out how to get a good load worked up and then try to get a good group with my, "Cold Shot" target. Does anyone have any ideas on how to home in on this? Actually, I have put this in my, "So much to do and so little time," folder. I always wondered if the people that reload for certain military snipers have a way to reload for this.
5. Not really related...I use to do this years ago, buy loaded cartridges and use the brass for reloading. I come to the conclusion that this is almost a waste of time and money. How much is one really learning from shooting those - one still has to start from scratch and work up a good load. Isn't it a safe bet to say that chances are that any over the counter cartridge is not going to be the better load for your rifle? I think the better route to go is just buy a bunch of the same new brass and go from there.
6. Whenever I see words like; exact, true, precision, best, only, the highest standards, and air gauged, I just wonder. And one that really sticks out with me, "This is the only..." Yes, one can see this often, 'This is the ONLY way to do such and such'.
7. I have an idea that as soon as the necessary laser equipment is cheap enough and available, the barrel makers will be touting that instead of their 'Air gauge' claim. I am not completely foreign to Air Gauges.
8. I have seen where people have commented that measuring powder to much precision is absolutely not necessary and...and have claimed that others back them up...they can shoot 3 inch groups with the best of them. What can one say to this?
Please don't take anything I say as being disagreeable or argumentative, It is just my thoughts and opioions. As it has been said, If a person has never been wrong, he hasn't done much.

[ironhead7544]

I know a barrel maker. He uses this type of lap. 50 strokes in 1/3 of the barrel length. 50 more in the second 1/3 of the barrel. And finally another 50 the full length. This give a slightly tapered bore towards the muzzle that he prefers. He is a national record holder so I think he knows what he is doing.

[5.56 123]

Hi - Good afternoon...I am NOT saying that lead lapping is NOT a good thing. I am saying that I have a feeling that lead lapping may not necessarily be the 'best' and 'only', and the easiest way to go. A barrel maker may be just cranking out barrels as a business. This is the way I think that in general, major barrel maker thinks. He can make a product that doesn't need to be consistent from barrel to barrel. He makes a barrel that looks good and has so much of the normal advertising lingo to go along with it and leaves it up to you to find that 'good load' that it likes. If enough shooters find that they can win competitions with it, he is off and running. Now two big exceptions to this comes to mind - the rifle maker that makes his own rifles with the barrels that he makes or, barrels that he buys from someone and works up some loads that 'this' barrel and 'rifle' likes. He then sell this 'package' including reloading data with targets to show results...and if you are paying enough, he may even let you come to their place and he will show you first hand how the firearm shoots. Can't you see where this particular load will probable vary from rifle to rifle. I think the bigger money making exception to this is with those military contract firearm makers where they get that 3 to 4 thousand dollars per rifle with another 3K for a Leupold scope where the rifle was made to match the given military ammunition - uniformity has to start somewhere. I assume that a lot of this expense is due to the necessary rejection rate of the barrels. I don't want to be a hypocrite and say anything like it 'has to be this way' - I just think that this may be the most cost effective and practical way to do it at this time. Besides it is not the military's money, it is someone else's, like our's.
I just reread an article about a .308 made by Les Baer called the. "Ultimate Match rifle." with a Teflon coated barrel of all things. That must be some tuff stuff. First of all I don't believe one can believe everything that is written in a magazine gun article. But it looks like for $2,980 one can get this rifle with a signed certificate by the person that made it up and, "...a target showing two five-shot groups fired by Les Baer himself..." And this comes without sights. I am sure that this is a good shooting firearm, but this can mean a lot of different things...like maybe these were not the "only" five-shot groups that he shot.
Another little pet peeve that I have is where someone says that just because he knows someone he therefore implies that some of that person's talent or knowledge has somehow rubbed off on him.
Hey, I can honesty say that I am ex barrel maker...even an experienced barrel maker - albeit, an experience of one barrel. :-) And I hate to say this but I will...one time in 1975 my shooting club paid for my transportation to and all fees to enter a Winchester sponsored 'world' open shoot in Yokosuka, Japan...and I will humbly say this...I tied for first place in my class. I estimated that I shot 44,000 rounds in practice and shoots before that shoot. I later heard that it may have been a world record. I would have to check with Winchester to see if it really was and is still valid...I seriously doubt that...but this would sound nice if it were.
Anywho, spring is here and I am looking forward to some more shooting fun....I still maintain that learning is a 'good thing'. But one has to be careful with just what he learns...that learned stuff is not always 'good' and sometimes hangs around too long.

[felix]

556, your bullet #2 in an above post is the only one you can take to the bank. The others are just attributes or contributors to the content of #2. Anyway you can get a repeatable acceleration curve of the projectile is the object of the game, and is the only one which figures into the Newtonian physicals.

By the way, if you had to make 44,000 widgets in practice for my company to make good on a delivered product, you'd be fired.

... felix

[btroj]

Barrel makers who produce barrels by the Bushel basket and don't worry over quality don't sell many barrels to accuracy minded folks. These are the guys selling to e masses and to people who want inexpensive barrels. The BR and high-power shooters pay good money and expect a good barrel. Don't tell me that Krieger, Hart, Shilen, Lilja, and others are just cranking out barrels with no sense of quality control.

I have fire lapped barrels, had good results too. These were factory barrels on production guns. Eliminated thread choke and burrs left in barrel from chambering. NEVER would I fire lap the Pacnor barrels on my White Oak uppers for my AR. Why? Because these barrels were lapped at the factory and then chambered by a person who knows what he is doing and takes the time to cut a chamber without burrs in the throat. This takes time and that equals money. Does this matter? Darn straight it does at 600. I want a barrel that I know can hold x ring otherwise how can I know if I made an error or if it was my barrel?

Don't confuse factory barrels and true custom barrels. the cost, and expectations, are vastly different. When o buy a factory gun I expect to to some work to get it to my standards, a custom barrel should be good from the get go.

Want to understand more bout good barrels and what they can do- get a copy of Precision Shooting magazine.