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I posted this on CastBoolits, with limited suggestions/ My .358 just isn't shooting up to where it should, it seems. I shot maybe 150 jacketed bullets through the fresh bore, and have shot maybe 6-700 rounds of cast through it since. Occasionally I will get a decent group but suspect it was one of those random flyers things that all managed to stay together. Do you think the bore is broke in enough with this amount of shooting? Should I use some lapping method? I know it was covered on the old Shooters, but I didn't pay much attention, since I was mainly shooting "experienced" milsurps at that time. | ||
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waksupi, I'd try running JB bore paste thru on a tight fitting patch a few times and then test it again. I save bore lapping for the really bad Milsurps. Just my $.02 Orygun | |||
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Firelapping grit embedded bullets in general is a neutral-to-good sort of thing according to the current crop of gun writers (who are shooting jacketed bullets, of course), with the sole exception it makes your throat larger and makes it tapered a half thousandth to a thousanth. If you are going to lap-fit a specific cast bullet mold to the throat afterwards, this poses no issue to you. I always wanted to try the Aladin trick of wet mopping the bore ahead of a loaded round with a lightly wetted fine lap grit charged cloth patch, Aladin's theory being that it spared the throat itself (full of bullet at the time) from being attacked, but allowed the bore itself to be smoothed. Want a very fine lapping compound that is cheap and is already on-hand? Comet sink cleanser fills that bill. Wet a mop with that and stroke your bore with it between each shot while shooting 20-50 normal cast plinker rounds. I guarantee you won't have a greasy residue to clean out of your bore afterwards and it won't do anything damaging in any great big hurry, being very finely granulated grit. Watch out for the cleaning rod contacting the critical muzzle zone though. Oldfeller | |||
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Use Bon-Ami instead. It's pure calcium carbonate. I personally like simichrome, or the new fine JB paste. Polish, rather than cut, is probably called for first trials. ... felix | |||
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Save the "cutting" action to last, as a last resort so to speak. Use the military surplus ball powders when shooting to take advantage of that small calcium content. ... felix | |||
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I have to agree with Felix in that you want to polish not cut. There's a company that sells a product specificaly for polishing the bore and it's called Final Finish. I believe you can find it using Google. They gaurrantee just to polish not remove metal. Okay now for my two cents, I think with the number of condoms you've fired and the large number of cast that you shot that your bore is polished and you might want to move on to another area to attack for getting better groups. Let me say that once you remove metal from the bore you can't put it back and wonder if that isn't the problem? Joe | |||
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Felix: The JB Polish you speak of, is that Car Polish rubbing compound? Don [ 10-03-2003, 19:10: Message edited by: OLPDon ] | |||
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Well, I'll try a bit of polishing when I get back home Sunday. I've went over bench technique, checked scope mounts, action screw tension, and bedding. I see no problems in these areas so far. That is what brought me to this point. | |||
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Waksupi...how about the load? What are you using. I know when I bought my jug of 844 surplus I first tried it without a filler (Dacron/Kapok) and it was terrible, both in accuracy and leading. Then I put dacron in it and viola! It shot much better and bore was clean. Let us know what you components are and also whether you are engraving the boolit in the rifling and such. Joe | |||
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waksupi, I sorta hate to confuse the issue by adding still another suggestion, but here goes anyway. <GGG> If'n t'were me, the first thing I'd do would be to run a dry, tight patch into the barrel slowly, and just "feel" if there are any tight or snaggy spots. Depending on what you learn from that, you can decide what to do next. If there seem to be variations in bore diameter, they'll have to be leveled out. In that case, you can start with something like 220 grit, until the bore seems to be an even diameter. If there are just snaggy spots, those can be removed easily with much finer grit lapping compound. If the bore seems smooth and even, a little bit of polishing could still help a lot. Personally, I'm not an advocate of fire lapping, but many people seem to be pleased with using it. The couple times I've tried it, it didn't work too well for me, mostly because of uneven lapping the length of the bore. OTOH, I've hand lapped quite a few barrels, and have always been pleased with the results. My procedure is to use a solid rod and boreguide. I use a too-small jag on the tip, so I can put a couple layers of cut up tee shirt patches under a patch of old jean bottom. This gives a very tight patch with some padding underneath to get down inside the grooves. I saturate the patch with whatever grit compound I decide to use, and run it through the bore until it feels smooth. If you have to remove metal with a coarser grit, make sure you "feather" the lapped area. At the end of the lapping, make long smooth strokes to even everything out. FWIW, you can buy several grits of valve lap at most auto parts places. I prefer the water-soluble compounds because they're easier to thin and clean up than the oil-based. I'd suggest no coarser than 220 to start with (for an uneven bore), and I think anything finer than about 600 grit is overkill. I've started using Turtle Wax Rubbing Compound (about 500 grit) as a final polish. Or, you can buy regular bore lap in various grits from the gun outfits (for a lot more money). Whatever you decide to try, though, good luck! | |||
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I have to disagree with grumbles method of lapping. That method, with a patch, will round the sharp corners of the rifling off, and not produce an even lap, even tho he may think so. If I were to fire lap I would use Final Finish. Read this below...just punched in lapping a rifle barrel in google and this is one I found and one that I agree with and one that I believe is a better method for hand lapping then a tight patch. LAPPING. "No need for it, just wears the barrel out!" P.O. Ackley. Lead lapping the barrel is done to polish the bore and remove machining marks and also to remove any tight spots in the barrel and make it dimensionally uniform end to end. If you were to sit down and write a top ten list of barrel makers, past or present, almost all would lap their barrels. This process is usually done by hand, though the process is mechanised in larger shops. It also acts an inspection process for the barrel maker who can feel what is going on up the barrel. First, the lapping rod (an old cleaning rod) is passed up the barrel to within about four inches of the end and then, with the barrel held vertical, molten lead is poured into the barrel. The lead freezes onto the end of the lapping rod forming a cast which precisely matches the inside form and dimensions of the barrel. The lead lap is then pushed out and smeared with lapping paste like that used for valve grinding. The lead lap is then pulled and pushed up and down the length of the barrel for several hundred strokes occasionally adding more paste or oil. Because the big particles of grit are embedded more deeply in the lead than the small particles there is an even bearing pressure from all the particles of grit onto the steel of the barrel. The net effect is to polish the barrel rather than scratch it which would leave a mat finish. Lapping the barrel adds between one and three tenths of a thou' to the bore and groove diameters of the barrel and is used by most small custom barrel makers as the finishing process on the inside of the barrel. Lapping a barrel will improve the performance of almost any barrel - in some cases, startlingly so! Generally, lapped barrels will shoot well from the word go where as the same barrel not lapped may take a thousand rounds or so until it starts performing at its best. Contrary to Ackley's dictum, lapping will add to the accurate life of a barrel, not detract from it. My two cents and not meant to offend anyone, only meant to keep waksupi from ruining his barrel. Joe | |||
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How many barrels have you lapped with that method? To me, it sounds good on paper, but the mechanics of making and using that slug would be very difficult. But, who am I to argue? I've only used my method on a dozen or so barrels, with excellent results. I yield to those who always know better. Heck, none of my guns will ever shoot a 1/2" group with unsorted boolits any time I pick it up. Choose your poison, waksupi! <G> | |||
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grumble...actually I've lapped quite a few that way and is in fact the way I lap out the constriction in revolver bores where the barrel is threaded into the frame, mainly on Smiths. Personally I don't think Waksupi's bore condition is the problem to his accuracy. If you have really terrible accuracy it isn't the finish of the bore causing it. Joe | |||
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Waksupi, as far as I know, has never stated what brand rifle action this is or type nor what exactly his groups are nor what type of sights he's using. If he did I missed it. I'd like to know that. We do know he has a Douglas barrel. Joe | |||
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And, in all the rifles you've used the slug method on, you've never had any problems pouring the molten lead down the bore? I admire the steadiness of your hand. When you use that lapping slug, which wears faster, the slug or the steel of the barrel? How do you manage to keep the sharp land-molded edges of the slug nice and sharp so they don't round off the sharp corners of the lands? As the slug gets smaller and the barrel larger, how do you maintain an even pressure of the lapping compound against the steel? Or, do you have to make new slugs every 3-4 strokes? The "sponginess" of the rag method takes up the slack pretty well, in my experience, and the rags are pretty easy to replace when they start getting loose. Any method of lapping is going to round off the corners of the lands to some extent. I think that problem will be less with any method of handlapping, though, compared to firelappng. | |||
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Except for the very tight frame constriction in revolvers, the idea is to polish not remove alot of metal. If you have an inconsistant barrel, that is tight, loose, tight, loose, you had pretty much get a new better quality barrel. Joe | |||
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Are you shure the problem is the bore? I'd be more inclined to think a sloppy chamber or off center crown would be the culprit then the bore. My 350 rigby has a rough bore, but it still shoots well. Groups more then dropped in 1/2 after a competent gunsmith re-chamber the original buddy of a buddy's job. | |||
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quote:Starpaddle I enjoy reading some of your posts. So little real knowledge dispensed in a such a know it all manner. Just cracks me up. Grumble has it right about the tight/loose spots being discovered with a tight fitting patch. But where they ARE tells the story. If a bore is LARGEST at the muzzle your accuracy is very poor 99% of the time. Polygonal bores are the equivalent of rounded off lands whereas the bullet is just squeezed on the constricted areas. No lands at all. Some of those barrels are quite competitive too. --I'd have an expert evaluate the gun's bedding. --check the loaded rds for runout. --check the check bases for squareness. --try a known scope on the gun for a comparison. PO was a good one, but in today's terms he'd be a chisel 'smith. | |||
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Full of BS...Yawn | |||
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Waksupi, Please keep us posted on your rifle. I am not going to tell you what to do because you sound like you know what you are doing and besides, I am still trying to figure out my own guns. At one time I fire-lapped all my firearms and, while the barrels looked noticably smoother and they fouled less and were easier to clean, accuracy was unchanged. The lapping did make a very noticeable improvement in a particularly rough and uneven TC muzzleloader barrel. In it's original condition, it was quite accurate (1.5 MOA with iron sights) but extremely difficult to load a maxi-ball after about 3 shots. I firelapped it then lapped it with a lead lap, two or three times, until the worst of the tight spots were gone. Now it can be reloaded indefinitely. But no improvement in accuracy. | |||
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Well, i don't have time to go over all points tonight, so I will put this in. It is a VZ24 Brno action. the work was done by John King, so I will definitely rule out any gunsmithing problem. I have lead lapped ML barrels before, but have never tried a cartridge barrel. Same process, just haven't done it. I've tried about half dozen different powders, and may be trying to push things too fast. I have shot some lower velocity groups into about an inch and a half, but anything faster than say 2000 fps, I will have groups in the three inch range, with a flyer generally going out 6-8 inches. And some of the loads in the 1950 range will shoot into .75 inches one day, and the next be out to a four to five inch group. There is no reason this rifle should not shoot well in the 2200 fps range with good accuracy. The main bullet I'm working with is the Bator 200(233) in the Douglas 1-12" twist. Any suggestions are welcome. The only other thing I can think of is stock flex in the composite stock. I may bolt things into the old military stock, with a bit of wood cutting, and see if the stiffer stock will help. | |||
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I have used both and I would try the JB first. I wrap a patch double around a worn out bore brush and then coat it with JB. It is VERY tight at first but does a very good job ( also helps get copper out of a used gun before firing lead). For the lead lap I also used an undersized bore brush and a paper wad so the lead would stay only on the brush. I used my Lyman laddle to pour the lead. I used soft lead and NOT wheel weights. It also works great but is much more aggressive than the JB when used with fine grit valve lap compound. wrg-inc | |||
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I remember on the old board were I lurked, the link for the Bator designs. Two things stick in my memory about them. First was the sometimes 3 calibers plus of bearing surface, which many a accuracy cast shooter has found to be NOT the answer. The other was the excessive lube carrying capacity, which with speed can give varying results especially with harder lubes. I remember something Aladin wrote on the old board, about shooting a bullet thru slowly and catching it intact. Then cleaning everything and pushing that slug thru to feel the internal dimensions of the bore. If I remember right, he said often removing the tightest constrictions helped groups the most. And in that way you can find if the muzzle dimension is largest, which ruins accuracy. But if you've made 3/4" with a load the gun could just be picky. Or want a different bullet. | |||
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I may have found the culprit. On a hunch today, I slipped a business card into the front of my stock, giving some upward pressure on the barrel. I just shot one group with it this afternoon, with a load I had tried before. The group shrunk in half. So, I will try another layer or two, see which thickness works best, and then make a glass piller in the front, if that is what it seems to like. | |||
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