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Molly
06-21-2008, 11:03 AM
I stumbled across another neat little trick that may interest the PP crowd. It's a take-off from something I wrote up for the CBA a while back, but here's the whole story:

Some time back I bought one of the unfired Yugo 8x57 Mausers because they were such bargains. But when I got the cosmoline off of it, the bore was pretty rough. Not rusted, not pitted, but it looked like it had been finished with sandpaper.

I didn't want to throw it away, and at the same time, I didn't want to pour coarse abrasives down a new barrel as was recomended for conventional firelapping. I decided to try something a bit less radical, and used JB Compound on a bore mop the coat the bore of the rifle. Then I fired a light jacketed bullet load, used the mop again, fired another light load, etc. When I was done, the bore looked like a mirror, and without any noticable enlargement. I wrote it up, and several people have tried it with excellent results.

A recent discussion of various grades of paper for PPing and various PP lubes brought the experience back to mind, because I wondered if anyone appreciated the fact that TiO2 - added to make paper whiter - is also a very, very fine abrasive. You can get the idea if you just walk over to the wall of your room and rub it with a nickle. It'll generally look like you wrote on it with a pencil, becaue of the metal polished off by the TiO2 (& other pigments). I'm a retired paint chemist, and I knew about this, but just didn't make the connection before.

Anyhow, my first thought was to wonder if anyone had noticed any polishing effect from ordinary PP lead bullets. Then I put two and two together, and wondered what would happen if I 'lubricated' PP cast bullets with JB compound! Just finger rub it into the PP after wrapping, drying and sizing. Works great, and without all the trouble of the bore mop approach.

I wasn't trying to develop a more accurate load, and didn't test for accuracy (I shold have, but didn't.) I was trying to test another approach for polishing bores, and I got that in spades. FYI, I used a moderate load with wheelweight alloy in a 30-06. Nothing fancy, but it worked fast, easily and well.

So if you've got a rifle (or pistol for that matter) that's prone to fouling or leading, you might want to give this a try. If you happen to have a bore that has been rusted, it MAY be possible to salvage it like this, using an appropriate grade of very fine abrasive polish. I'd recommend that you steer well clear of the coarser abrasives often recomended for fire lapping. For some reason, the very fine abrasives like JB compound seem quite effective here, and polished the bore of the Yugo M48 in about 5 or 6 shots. I see no advantage to coarser abrasives, and I can see numerous potential problems they could cause.

Of course, the usual caveats apply: These results were obtained using components, equipment and techniques that will differ from yours, so approach this experimental procedure with great caution if you decide to evaluate it yourself. NEVER use experimental procedures of this nature - or any nature - with maximum loads unless you work up very gradually because the interactive effects could produce dangerous pressure levels. Since you are the only person controling most of the variables involved, you will have to accept full responsibility for the results of your judgement and practices.

Regards,
Molly

bcp477
06-22-2008, 12:12 PM
Interesting. I also shoot an M48, but one which I rebarreled recently, with a pristine, unmounted military surplus Yugo barrel. On my previous M48 barrel, I carefully "lapped" the bore with JB bore paste, after cleaning out all of the visible crud, as it was quite rough in the beginning. This was much more than simply cleaning the barrel with the JB - I really worked it over. This definitely made an improvement in the appearance, as well as the accuracy of the barrel. The process made a well-pitted barrel into a pretty good one.

As for my "new" M48 barrel, I have not followed the same procedure, as this barrel is in marvelous condition, especially for it's age (and thus, doesn't need it). But, I have noticed that, after shooting my paper-patched bullets, the bore is remarkably clean. I patch with white, lined notebook paper....and lube with Lee Liquid Alox. Perhaps the white paper is having a polishing effect on the bore, I do not know. In any case, I certainly do not object to the clean bore after shooting, as it just makes things easier.

Molly
06-22-2008, 12:44 PM
Interesting. I also shoot an M48, ... On my previous M48 barrel, I carefully "lapped" the bore with JB bore paste, ... This definitely made an improvement in the appearance, as well as the accuracy of the barrel. The process made a well-pitted barrel into a pretty good one.

As for my "new" M48 barrel, I have not followed the same procedure, as ... after shooting my paper-patched bullets, the bore is remarkably clean. ... Perhaps the white paper is having a polishing effect on the bore, ...

The results with your first barrel are no surprise. But it's a shame you had to do it all by hand. Believe me, I've been down that road, pouring laps, etc. It's a BUNCH of work. Half a dozen shots of light loads using JB compound is the easy way to do it.

It wouldn't surprise me a bit if you aren't getting some slight polishing effect from the PP in the second barrel. The TiO2 levels in various grades of paper will vary considerably from grade to grade, and there are other pigments (clays, etc) that probably make a contribution as well. I can see several explanations off the top of my head: First, the PP helps clean the fouling residue from each shot, and 2nd, each shot polishes the bore a trifle more, making it less likely to foul, and 3rd, paper simply doesn't have the fouling potential that cupronickle has. Any combination of these could be at work, and who knows what else? Hmmm. Anyone out there work in the paper industry that might be able to comment on levels of additives in different grades of papers?

Regards,
Molly

Digital Dan
06-26-2008, 08:56 AM
You can achieve the same result by firing mild loads with an unlubed paper patch, or dry paper. Half a dozen or so shots will turn a gray bore shiny.

Glossy papers are generally so due to the inclusion of kaolin in the mix. It is a clay like material commonly used in paints and other pigments....and cat litter. It is very abrasive, use at your own risk.

sagamore-one
06-26-2008, 05:07 PM
I used a similar approach on a Blackhawk in 45 colt . The barrel was sooo rough that even jacketed bullets leaded the bore... well almost that rough. I destroyed my Lewis lead remover trying to get the lead out. The good people at Ruger examined it and told me there was "heavy duty machine marks" in the bore and that my cast linotype alloy boolits were too soft, that I should use jacketed only. I cast up some nice Keith s w c boolits, hand applied J&B to the lube grooves, and loaded them up. After 25 shots the bore started to clean up. It may have been an agressive method... but it worked. Much more satisfying than dealing with customer non-service at Ruger.

Molly
06-27-2008, 06:06 AM
Some hold that a barrel can be too smooth, thus suffering from lube failure and fouling, to the degradation of ACCURACY. BvT

So I have heard, particularly in the context of black powder ML rifles. However, I have never seen, much less had opportunity to examine such a case. Nor have I ever heard a reasonable explanation why this might be so. I personally regard it in a class with 'leading is caused by lead rubbing off as the bullet goes down the bore.' In other words, someone dreamed up and put forth as factual, without a shred of evidence or logic that I have ever been able to discern.

And before you condemn a barrel as 'too smooth', you might reflect that - without a single exception that I know of - the master gunsmiths of the muzzle-loading era hand-lapped their bores for the greatest smoothness possible. This is a very tedious and labor intensive process. I've done it. And I assure you that while someone MIGHT try it once just out of curiousity, there won't be many willing to do it again if the smoother, more uniform bore didn't help.

Molly

Molly
06-28-2008, 01:50 PM
... Couldn't agree more about your approach-- "use the least aggressive method that shows some result and don't overdo any bore polishing" or something to that effect. ... - it's all many bores need to reach desired smoothness and live a normal, long and hopefully accurate life.

Couldn't have said it better myself. Thanks.
Molly

joeb33050
07-13-2008, 01:03 PM
From "SHOOTING AND FISHING", July 5, 1888
THE AMERICAN RIFLE
(Development of 40 years)
BY H. WARNER
(Copyrighted)
FALLACIES ENTERTAINED BY RIFLEMEN.

In these days of almost universal rifle practice by the young and middle-aged men of the United States, and the interminable discussion of questions incident thereto, one would naturally suppose that the requisites for a fine shooting rifle should ere this be well defined and fully understood by the majority of our marksmen.
Yet this is not the case. There are certain characteristics generally supposed to be indispensable in the make-up of a perfect shooting rifle, because so often described and dilated upon by would-be authorities on the subject, that the shooting world has come to regard them as necessary, or in the line of facts established, which may govern in all cases.
Many of the conclusions thus forced upon the shooting fraternity are misleading in their nature and at variance with facts.
Fallacy No. 1. -Among the fallacies thus established, none is more prevalent than the belief that a rifle designed for the finest shooting must be finely finished on the inside of the barrel.
Mr. W. W.Greener, of England, in a work on rifles thirty years ago, fully committed himself to this theory, and more recently Dr. E. H. Pardee, a noted rifleman on the Pacific coast, in a dissertation on "Ancient and Modern Fire Arms" (published in the Breeder and Sportsman of San Francisco, Cal.), reiterated the same opinion, in words so like those of the author first named, that they would appear to be a quotation without credit.
It is doubtless safe to assert that ninety-nine out of every one hundred marksmen of the present day adhere to the same belief. For, what is more common amongst riflemen after examining the inside of some new gun just brought to their notice, than the remark: "That gun is finely finished inside. It must shoot well! See what a polish it has!"
Notwithstanding this unity of opinion and general belief in the efficacy of high polish as an adjunct to fine shooting. I make the assertion that an extremely fine finish on the exterior of a rifle barrel is not necessary, nor even desirable, for in many (if not most) cases it will be a fruitful source of erratic shooting.
If asked to give my reasons for drawing such a conclusion, the most natural and direct answer would be that it is the result of repeated test and experiment-simply, I have found it so in practice.
To the inquiring mind such an answer would probably be unsatisfactory, and, if still disposed to controvert the deductions arrived at by experiment, and, ask me to explain why a high polish should give inferior results in shooting, the answer must necessarily partake largely of nature of opinions or theories, the correctness of which it would be difficult to demonstrate or establish in any other manner than by experiment. Theories can never stand when opposed to facts, but a little elucidation of both may serve to modify a seeming difference, and bring them nearer together.
In this view of the case I will proceed to give some other reasons for the faith that is in me.
All who are familiar with the subject will agree: First-That uniformity of condition, in gun and ammunition, during a series of shots will be more conducive to uniform shooting than a varying or changeable condition of the same.
Second-That in repeated firing, heat is the most important, if not the only element that enters in to disturb the normal condition of the gun-that friction generates heat, and therefore, the rapid passage of the projectile along the inner walls of the rifle barrel must be regarded as an accessory to the heat developed by the explosion.
This combined action of the two agents produces a heat most intense, and its influence on the barrel and projectile being as rapid as thought, it would, if of any considerable duration, be sufficient to melt a leaden projectile, but the passage of the bullet out of the barrel being so short, it seldom terminates in melting, although I have thought on two or three occasions, several years ago, that I obtained such results with extremely heavy charges of powder, in a long, heavy-barreled rifle having a chamber in the breech much larger than the bore of the gun. Be this as it may, the effect of heat on all, or nearly all, metallic substances, is to expand and soften them, more or less, according to the intensity of its application. It is not, then, unreasonable to suppose that its influence as applied in the process of discharging a rifle would be sufficient to materially change the density, size and fit of the bullet. Such changes would affect the flight of the bullet just in proportion to their magnitude, and their magnitude would depend entirely upon the amount or degree of heat developed.
Heat, then, seems to be the chief obstacle we encounter in our efforts to secure uniform shooting. Could we find an explosive which developed no heat, and a projectile which encountered no friction, we should have made a decided advance in the science of gunnery.
Since we are unable to overcome the influence of heat, the best we can do is to reduce it to a minimum. It is plain we cannot dispense with, or greatly modify the explosive in general use to-day, and therefore cannot hope to make much reduction in the heat developed from that source. There seems to be but one direction in which we may look for improvement.
As I have previously stated, friction generates heat, and the friction of the bullet in passing along the barrel is therefore a natural ally of the explosive in producing an element so detrimental to uniform shooting, and, the worst feature of it is, that the very considerable augmentation of heat thus produced, occurs in the very spot to make it most disastrous (i.e.) on the abrading surfaces of the patch, and culminating near the muzzle of the gun, where it is so desirable that the delivery be easy and perfect.
This frictional heat is often so intense as to scorch and weaken the patch. It is to be deprecated always, and guarded against as well as circumstances will permit. Hence the frequent resort to lubricants of some kind by many of our prominent marksmen. From the above it would appear that whatever tends to reduce friction, or render it uniform, is an aid to good rifle shooting, and this brings me up to the point under discussion, and the proposition previously stated, to wit: "Extremely high polish is detrimental to fine shooting."
I make this statement as a fact, substantiated by thorough test, but I offer in explanation to those who doubt it, the assumption that two surfaces finely finished and perfectly fitted to each other will adhere to each other more firmly and produce a sharper friction when moved rapidly and forcibly across each other than they would if the surfaces were more coarsely finished.
In point of fact, two pieces of fine metal with flat surfaces may be so closely fitted to each other as to make it extremely difficult to separate them, or to slip one upon the other. Two surfaces fitted so closely as to exclude air or any other substance become almost like a solid piece, and the same principle holds good when applied to a gun and its projectile.
If the inner walls of the barrel be polished down to a finish so level and smooth that there is no scratch on the surface deep enough to contain air or lubricant while the projectile passes over it, the result will be extreme friction-great generation of heat-a burnt patch (if there be one to burn) and an erratic shot, quite frequently, for it must be remembered, that the explosion of the powder will upset and fit the bullet to the gun, although it may not have fitted closely when put in. After the explosion the surface of the bullet will conform exactly to the surface of the gun, even to the exclusion of air which might have been between them before, and the fit thus made is not likely to become any looser on the passage out. On the contrary, the heat, generated by friction, as well as that imparted by the burning powder, would have a tendency to expand the bullet and make it fit more tightly if possible. It is this tendency to expand, and present increased obstruction to the propelling forces, thereby inducing a second upset of the bullet on its passage out, that results in wild shooting.
This expansion by heat is more likely to occur in highly polished guns than in those of coarser finish, which give better facilities for lubrication, or the presence of a little air occasionally between the surface of bullet and walls of barrel.
Amongst riflemen of ripe experience it is well understood that that guns by much use become (to use a common expression) "shot out" (i.e.) there is a falling off in their shooting qualities. This is usually ascribed to a worn condition of the interior, that is, to a certain extent, true; but not in the ordinary acceptation of the term worn; for, while the rifling may still be of proper depth and form, to give good results, the surface has, by continued wiping out and shooting, acquired so high a polish as to prevent it. One who is familiar with this phase of gunnery will have no difficulty in detecting it, even without looking through the rifle, as he will readily detect it in wiping the gun, or even in the report, if he listens carefully for any considerable number of shots.
The remedy in such cases is to carefully work over the surface again with proper tools in such a manner as to break up the high polish and replace it with a coarser finish.

Molly
07-13-2008, 05:36 PM
I was participating in a recent bull session of local gunsmiths yesterday, and brought the subject of shooting slick up for comments. The comments were quite interesting, and included things like:

“(Local BP gunsmith) will swear its true, and says that he's experienced it several times. He says nothing will cure it except to wrap 000 or 0000 steel wool on a jag and run it up and down the bore for half an hour or so to rough the bore up a bit.”

Another 'smith opined that while he wasn't into BP much, he'd sure take exception if anyone tried to tell him that the same thing would happen with modern guns, and he hadn't seen anything like that in several decades of smokeless powder cartridge guns.

Another 'smith laughed, and said that a lot of BP shooters used various oils to lube their patches, and that some oils would form hard cakes with BP residues, especially if shot enough to warm up the barrel. Said a lot of dried / hardened oil or grease lubes wouldn't clean out well with soap and water (the classic BP cleaning solution) and left a residue that would dry and harden with time, kinda like linseed oil paint, and this would cause all sorts of accuracy problems like preventing the ball from seating properly tight against the powder charge, etc. He thought that all (the local BP 'smith) was doing to restore his guns was to give them a good thorough cleaning with steel wool.

The general consensus was that the notion didn't seem to have much merit, and that included the opinion of one 'smith with considerable BP experience, who said he'd heard of it, but never seen a case.

Me, I dunno. I’m not into BP. But at least the cleaning explanation accounts for both the slow deterioration of accuracy and its restoration by 'roughening' the bore, which would surely be vigorous enough to remove any tough, water-resistant caking deposits. I think this would be worth some serious investigation by someone interested. If'n I were interested enough to pursue it, I'd maybe start by getting a rifle that was 'shooting slick' and see if pouring the barrel full of paint remover overnight visibly removed anything, or restored / changed accuracy. At least, this would have the advantage of not removing any metal from the bore, so it would still be 'slick', and accuracy should still be the same.

If paint remover didn't give me some hints, I'd pour some naphtha down the barrel and scrub the dickens out of it with steel wool. Then I'd dip a magnet in the cleaning naphtha to remove the steel wool and its fragments, and see what I have left. If it's still water-white naphtha, I'd say that the residue idea was all wet. But if the naphtha has a lot of specks that aren't removed by the magnet, I'd find out what they are, and how they got there. How? Slosh some of the same steel wool in naphtha, tearing some of the wool into small bits. Soak well, and remove the steel wool with the magnet. What does the naphtha look like? If it's still got a lot of specks, they’re are coming from something in the steel wool (a rust preventive perhaps) and not the bore. Simple reflection will suggest a lot of easy, simple tests that can be very informative. And believe me; a single experimental test will trump a thousand expert opinions to the contrary!

If that didn't tell me anything, I'd take a good shooting rifle and fire a few groups to establish a base accuracy performance. Then I'd get some chrome polish to lubricate my patches with for a while. Shouldn't take too much of that to give a bore that was as slick as a mirror. Then I'd re-check accuracy with the original load. Then I'd scrub with steel wool and test accuracy again. Somewhere along the line, I think I'd learn something.

Frankly, the whole thing sounds rather far-fetched to me. But as soon as I say that, I'm reminded of the huge difference that changing cast bullet lubes will make in modern rifles.

And I've personally - and repeatedly - experienced poor shooting from dried residues of Hoppes until I got it shot out. - or unless I scrub it out with a bronze brush and paint thinner before shooting.

So, mebby there's something to it after all. Even with smokeless rifles and jacketed bullets, first shot accuracy has been a conundrum for a long time, and maybe this is part of the explanation there too.

Who, ME? No thanks, I'm not into BP. I don't have time to handle the cast bullet projects I want to do as it is. But there's no reason one or two of you fellows couldn't have some fun is there? Go to it, and let us know what happens.

So many interesting questions, so little time ....

Regards,
Molly

BTW Joe, what's Wagner's Fallacy #2? Or are you going to hold that one back until you're done milking this one? (VBG)

Molly
07-15-2008, 07:18 AM
If there is any interest on the point of refreshing a bore I suggest reading the Warner-Lowe letters or some of the older books on BP. ...

Hey Dan,

I mentioned "The Madman of Gaylord's Corners", (whose slug gun was a 0.6832" bore) and decided to re-read that, among some of Lucian Cary's other stories. Found a quote that will fascinate everyone on this thread.

From "The J. M. Pyne stories & other selected writings" by Lucian Cary" (Edited by Guy Lautard), pages 24 - 25, discussing Harry Pope and the techniques he used to produce his barrels:

Quote: "The refinement in manufacture (developed by Pope) was in the slightest possible use of the lapping rod. It was customary for most barrel makers to take off the burrs left by the rifling cutter with a lead lap coated with oil and emery. Heavy lapping obliterates the niceties of the original cut. Pope wanted to cut his grooves to his predetermined shape, and he did not then want to spoil this shape by lapping. However, he usually found it necessary to do a little lapping. To distinguish the light lapping he did from the heavy lapping of others, he called what he did "polishing." End quote.

Pope is generally credited with making some of the best barrels of his day, and for generations to come. His barrels covered everything from BPML match rifles to military production of the 30-40 Krag. But I never heard of any of his "polished-bore" rifles being accused of poor accuracy due to 'slick shooting'.

Regards,
Molly

docone31
07-21-2008, 10:19 PM
Freshing a barrel was fairly common back in the 1700's, and early 1800's.
The barrels were a damascus variant, then reamed, and rifled. The powder was corrosive.
Even through we today fire many times more rounds through our barrels in one shooting session, back then, the powder would eat the bore.
Rather than purchase a new rifle, a barrel was set up to be Freshed.
An Hawken as an example was usually .52 calibre. After firing many rounds, the rifleing would become pitted. The rear tang would be removed, the bore re-reamed, and re-rifled. In most cases, using the Hawken as the example, and this is only the plains variant. Hawkens came in many other calibres, in most cases, the .52 would become .54. The tang would be retorqued, the barrel installed, and the shooting would commence.
I have seen many plains rifles. The percussion cap was the major culprit with pitting on the surface of the barrel, around the nipple. I suspect the priming compound also played a major role inside the barrel.
I have seen Freshing machines, both handmade, and factory exhibits. It is fascinating. The handmade machines were hand powered.
Perhaps 25yrs ago, I had the chance to visit an old Pennsylvania rifle maker family. The original family still lived there although they no longer cared about great grandpa's livelihood. I got to see the original shop, complete with major cobwebs, old wooden machines full of worm holes, old dust, and even a mouse nest. In the attic was a supply of made up barrels, dust thickly on top of them.
If you have ever been to an old barn, with an old hay loft, it was the same kind of dust. The forge, and bellows were unuseable. The leather of the bellows was about gone. What was fascinating was the barrel mandrel. The stub was only about four inches long. The barrel reamer was incredibly simple, and the rifleing machine was amazing. It was mostly wood!
The twist logs were still there, full of worm holes, but still there.
I was really amazed.
They did indeed Fresh a barrel. It was fairly simple to someone with experience. Instead of taking months to make a rifle, it took about a day. Remove the barrel, ream the bore, and rifle it. The finishes were browning. This person made his own browning.
The family had no interest whatsoever in the "goodies" in the barn. They just did not have the whatever to toss it, or sell it. Only the remaining Grandpa, they called him "Grumpy" knew anything about it. He and I spoke for a while.
He remembered draw filing the lands on the barrel, and using silk to straighten out the barrel. He also remembered driving the old Harley with the carbide lamp, still in the barn.
I hope I did not go too far off topic, but Freshing jogged my memory. I have seen hand reaming, and hand rifleing, but those were made from old drawings.
In my opinion, they were craftsmen in those days.
The Great-great grandchildren were suprised anyone was even interested.
I sure was.
I am also sometimes greatly self absorbed.
Molly, I hope your wife gets through this with strength. I am at the age, where it is either my wife, or me. I ask myself, will I be there for my wife? It sound like you are for her.
Todays medicine is indeed different than 20 yrs ago. I sure hope they do magic for her.
It sounds like you are going to be there for her.

Molly
08-18-2008, 12:08 AM
Hi fellows,

I've had a few questions from citiboy that I thought might interest some of you too. He was gracious enough to give me permission to quote him as follows.

Also, for all of you who have asked, my wife is having a pretty tough time of it, though she's vastly improved over what she was. Right now, we're looking at a lung transplant, since the doctors really can't do much for her current condition otherwise. But on the bright side, the doctors say that she's in good enough health otherwise that they're going to move her to the top of the list, so we're probably going through that in the not too distant future. I'll generally remain in lurk mode when and if I get the time.

>I am getting ready to make up some firelapping loads for my 03-A3 with a 2 groove barrel and would like to pick your brain. I will be using some 150 grain spire point Sierra(?) bullets and some IMR4198 powder I want to get rid of. Looking in the Lyman 3rd edition CB book they list the Lyman 311440 and a minimum load of 25 grains for a velocity of 1776 fps and a pressure of 13,700 CUP. Does this sound reasonable? I thought I would start out with 10 rounds.

Yeah, it does sound reasonable as far as I know, but it's not something I've tried. I'd approach it a little differently: To me, 4198 would be too fast burning for my comfort. Fast powders jump pressures in a HURRY if something goes wrong with your logic - and that's not something you want to play with. The JB WILL increase resistance and pressures. If it were me, I'd use a more normal powder, and tend toward the slow side for added safety margin. For example, I've got an old Hodgdon manual that suggests a starting load of 56g 4831, for 2366 fps and 30M CUP. And I'd even cut that back by a third.

Remember, you're not trying to duplicate factory ammo, or develop a 1000 yard Palma match load. All you need to do is push the bullet through the barrel, and live through the experience. Stack the odds in your favor as much as you can. And even then, I'd recommend firing it from a tire with a string. Yeah, I'm an old scaredy cat, but I've got scars from a rifle blowup to justify it.

>How much JB did you load on the bore mop? It seems to me if there is too much, it will be squeezed out as it enter the throat ( if you start at the chamber end) and there will be a big gob in the throat. What do you thing about starting at the muzzle end?

Gee, I dunno. "Some" would be the only answer I could give you. I dipped the mop in the JB jar and scooped up a gob. Then I rubbed it into the mop with my fingers until it seemed pretty well saturated. I squeezed off the excess with my fingers, and pushed it through the bore several times to make sure it was well coated. I DID look at the chamber after mopping it, and there were no big gobs anywhere. (I'm quite familiar with pressure excursions from grease in the chamber!) As far as starting at the muzzle end ... I wouldn't do it myself: The muzzle is too important to good accuracy to risk damaging it any more than necessary. Granted, JB on a cotton mop isn't likely to damage it, but why not mop from the breech, which is easier, and runs no risk at all? I guess it's the old maid in me, but I like to take the most conservative approach possible, no matter how unlikely the prospect of problems might be. I've seen too many "highly unlikely" things turn out to be unexpectedly - and uncomfortably - real when put to the test. And as I said, I have the scars to prove it!

> I hope your wife is feeling better.

Thanks. It's a day to day sort of thing, but so far, we're getting by.

Hope this helps. BTW, a new posting about getting great results by bore polishing with JB compound just went up on the Cast Bullet Book website. I haven't had a chance to read it yet, but you might want to look it up. (Oops! That's what I get for assuming. I read the comment (an addendum to this bore polishing thread), and while it did say that the bore polishing with JB worked well, it mostly dealt with stuck bullets from too light a load to overcome the friction with the JB compound.)

If you don't mind, I'd like to post this PM on the Cast Boolits topic, because I think you've asked questions that others would like to know about. Any problems with that?

Take care.

Molly

Molly
09-07-2008, 05:48 PM
Not too sure where this can / should be posted because it isn't PPing as such. It's more gunsmithing than anything else I suppose, but TWIMC; I got this fire-polishing thing started a while back by publishing a short article in the CBA's Fouling Shot describing some fire polishing I did on a Yugoslav 8x57.

Well, as it happens, I've gotten both my stepsons into shooting, and last weekend, one of them expressed an interest in the nice milsurp 8MM that was taking up space in my safe. I haven't done anything much with it (crude iron sights and old eyes are not good bedfellows), so I invited him to take it back with him and borrow it for a year or two (VBG).

He just called to tell me it shoots GREAT!! To some folks, 'great' means that he hit the barn both times, so I questioned him about the details. He said he'd just shot at a 1" square on a sheet of paper at 100 yards, and managed to keep all his shots within an inch of it. That translates to a 3" group with iron sights, which may not be anything to compete with in a benchrest match, but at the very least, it should be enough to indicate that firepolishing your bore isn't likely to do any serious harm.

Another shooter (who also posts here, but I don't have permisssion to quote him) wrote to tell me that he'd run a few firepolishing shots through his 2-groove springfield. He'd followed my advice about using a jacketed bullet and a powder charge in the 50% of normal ballpark, and had no trace of trouble. Results: Incomplete at the moment, as he plans to do some more firepolishing, but the pressure to push a patch down the bore was notably more uniform than what it had been.

I'm continuing to get more and more positive reports on fire-polishing, and to date, not a single adverse comment. So come on fellows, get your feet wet.

Now I just need to get my stepson into cast bullets...

Molly