vertcial stringing

[eagles]

I have a lever that out of a cold barrel verticaly strings the rounds . at 75 yards maybe a three inch string . After four or five shots they start to group well . Different ammo seems to do the same thing . It seems the barrel needs to be warm to shoot . Is their any thing that can be done to try and correct this tendency besdies throwing rounds away before getting serious ?

[JB]

Does it do the same thing from a dirty cool barrel? I was just wondering it was a dirty versus clean issue rather than hot versus cool. I've seen a number of rifles that string shots from a hot barrel, but don't remember seeing one string them from a cool barrel.

[eagles]

it is when it is first fired , clean that it strings them . I have not waited for it to cool down again dirty to try . Non the less it is constant go tho the range first shots string , after four or five shots it groups . You can switch the loads next time and get the same results , the ones that shot great on the second group string if shot first and the bad ones from the first time start grouping .

[Pisgah]

You may be right that warming is the problem. But JB has a very valid point -- I have a 336 that, when clean, will do the same thing until if has had 3 or 4 fouling shots. That is why I take it to the range at the start of every season to check the zero. Once I have done that, the bore does not get cleaned until the season is over.

[eagles]

actualy warming is not the problem but the fix , bad when cold good when warm. It makes no scientific sense to me at all that by adding debris in the barrel which would by its nature be random in size and amount , increase accuracy some how , which means random dirt , scattered in a random pattern increases consistancy ?

[Blaine]

My 336 throws shots from a dirty, but cooled off barrel pretty good.....If I shoot more than two or three, they start stringing vertically..... I've always wondered if this means that the barrel is being pinched by the forearm. Also, are you holding the rifle, or putting it on a rest of some sort? I get different POI from holding and resting....

[eagles]

In your case it sounds as though heat is the culprit . My gun is locked in a lead sled type device so the pressure is constant and equal . Only thing is as mine gets dirty and hot the accuracy increases , . I can think of two possible reasons .1 The barrel is to small for the slugs as it heats and expands the slugs fit the barrel better 2. The barrel is to large and the debris in the barrel creates a better seal , wild gueses . My gun is a 450 marlin , winchester timber carbine model 94 .My Big bore 375 has no such quirks. eventulai am going to try a bunvh of different ammo , clean between shots and cool between shots and see what happens . Still looking for ides though ?
i

[Kansas Ed]

IMO all rifles and handguns will shoot better after a fouling shot or two. Best as I can figure is you have a clean barrel the first shot, you will never have this variable again after the first or second shot...but after a couple of rounds, you have "dirtied" the barrel, at which point you have a more consistent set of circumstances for the next rounds that are fired....no matter if it is the next 5 or next 25 rounds. I never judge the accuracy of any firearm from a clean barrel...I shoot a couple or three and then start my range session. Then I don't clean the barrel unless the firearm is to be stored for an extended period of time. Dirty barrels aren't a problem, moisture is the problem...so keep the moisture out and a dirty barrel won't ruin the rifle.

Ed

[Chuck 100 yd]

My Marlin .308MX would do that at first using the LE ammo.
I have worked up hand loads for it and they did not exhibit that stringing as bad as the LE ammo.
After about 100 rounds of shooting the stringing just went away on its own. It can be counted on now to put that bullet right where the cross hair is.

Have you fired any hand loads in it? Maybe another bullet or velocity change is needed to get her to settle.

[TedH]

It depends on the particular rifle. I've got one heavy varmint rifle that takes at least 6 shots before it gets down to business, then puts them all in one hole. With your levergun though I would first try and let it cool, completely, after you shoot enough to get a good group. That way you'll know if it's something shifting from heating up, or the barrel needing a little fouling, and progress from there. Don't worry about cleaning after every range session. There is not any real reason to be cleaning that often anyway.

[JReed]

As others have said shoot it with a fowled cold bore and see what happens. My Handi in 308 is really bad about a clean cold bore but if I leave it dirty it shoots very well cold. I have a couple of rifles that act the same way but the .308 is the most noticeable.

[Tycer]

http://leverguns.com/articles/paco/chapter23.htm

Read this and see if any of the suggestions might help you.

[Nath]

My 94 use to do this, the funny thing is it was not doing it at first! One thing I never tried but wished I had was shoot it with the fore end removed. I tried allsorts with mine, altered this and fiddled with that but nothing would cure it. Made no difference if it was sighted on a cold barrel or hot it got as I could not count on it. I was convinced it needed a new barrel!

The 94 has dovetails and grooves cut into it and a flat grind up by the chamber, I am of the belief that if they are not cut true to each other then some bending will take place, bending will happen anyway and a 450Marlin will warm it up quick I imagine hence a verticle string but mine did it diaganollly.

I would love to see how a 94 shot with machined rings/bands that were a tight fit !

Nath.

[eagles]

Thanks for the acurizing tips but I think this is a gun now that may just need to shoot with a dirty barrel . Everyone keeps saying when the gun warms up the problems start but remember mine is the opposite . After a few shots it gets real accurate , so nothing is warming up and putting pressure to hurt accuracy . Also take a look at the Winchester Timber carbine , no barrel bands and a half mag tube, allmost a free floating barrel . I gues it is better to have a gun that gets better with each shot instead of worse !!!!

[Nath]

Hmmm , I thought there was a barrel band and a fixing for the mag tube.

How is the fore end held on and the tube held in the reciever?

Nath.

[eagles]

I said that wrogn it doesnot have the normal frontal barrel band or screw from a full mag tube . it has one barrel band in the rear that is loose and the mag tube screw is not tight and of course not at the muzzle . My gunsmith, Reesers In Pa said when he looked at it this and shot it is allmost free floating as I had asked him to see if their was any pressure anywhere . He siad their was no interferance by anything .

[Nath]

Thats ok eagles, I had mine all loose too but when it was all tight from the factory it did shoot better!
I did consider bedding the fore end and making the bands tight again but never did. I should of at liest tried with just paper to eliminate it.

My bolt gun will shoot it's first round out of group on a clean bore but not by much.

Good luck

Nath.

[eagles]

I did not have to loosen the band or screw from the tube it as was never real tight to start with when I got the gun . When we checked it, it was relatively easy to move those screws so it was left as is . I was allways told it was when they are under heavy pressure they can cause accuracy problems and again, once three or four rounds are fired , the next four will make a very good group . Four shots at 75 yards about one and a quarter inches last time . but the first four , a vertical string , of maybe three inches .

[Bill_Rights]

Fouling inside the bore is not random, scattered or messy.

eagles said: It makes no scientific sense to me at all that by adding debris in the barrel which would by its nature be random in size and amount , increase accuracy some how , which means random dirt , scattered in a random pattern increases consistancy ?

Kansas Ed said: Best as I can figure is you have a clean barrel the first shot, you will never have this variable again after the first or second shot...but after a couple of rounds, you have "dirtied" the barrel, at which point you have a more consistent set of circumstances for the next rounds that are fired....no matter if it is the next 5 or next 25 rounds.

Ed is right. The propellant blast liberates incredible heat, pressure, chemical reactivity of "free radicals" and even electrical plasma within the bore. What is NOT stable or clean in that environment is the solvent or oil that you last wiped the bore with. It just gets chemically chewed up in that explosive chemical environment. And it (the oil) gets destroyed in messy, random ways, and incompletely in places. What IS STABLE, in a steady-state sense, from shot to shot, is carbon residue from the burned propellant, lead rub-off from the bullet and even copper rubbings from jacketed bullets. By steady-state I mean that whatever gets dislodged or vaporized by one shot gets replaced by the residues of that same shot. All three of these (carbon soot, lead rubbings and copper rubbings) both reduce friction (compared to bare gun steel) and smooth the inside of the bore by filling pits (microscopic or nearly so) in the surface of the steel. The passing bullet and the high pressures both force these (soot and rubbings) down into the pits and simultaneously squeegee off excess, just like a trowel wiping grout into gaps between tiles. The surface produced by the act of shooting is as near to perfection as can be had, much better than a purpose-polished surface could be, and also self-healing to a certain extent.

Now, if you want a real question that baffles science: Why is the initial drift of the bullet always vertical? Should be random. Let me risk as guess. Do you store your rifle (after oiling the bore) on a horizontal gun rack? If so, maybe the oil "puddles" somewhat along the bottom of the bore, giving you a top-to-bottom asymmetry? (DISCLAIMER: science can "explain" anything - doen't mean the first "explanation" you come across is unique, much less uniquely correct.)

[eagles]

interesting . Gives some credence to products like Microlon that I have some of . Great for finger prints .Will try it , it operates so it says by using this heat etc to fill in the pores , improving velocity and accuracy after using it in the bore between shots for ten shots , adhering it to the and in the metal pores . If this is so accuracy should improve or this problem should be greatly helped . No my gun is stored verticaly .and has you said , if the oil was random debris, the vertical string should not be so consistant .

[Bill_Rights]

Microlon, eh? Can you give a little more info from the container, like the manufacturer and such?

So you store the rifle vertically. That throws out the oil puddling idea. I could speculate that there might be some top-to-bottom oscillation of the bullet as it goes down the bore, enabled by the oil film somehow. But that would be some kind of resonance or bullet-fit-to-bore situation, and I believe you wrote that you've seen the same stringing with several different loads, which would be kinda a miracle if bullet oscillation was the cause. I dunno. Maybe we all get some kinda of stringing at first and are just not careful enough to observe it?

[eagles]

Microlon GUN JUICE , manufactured by Microlon is suposed to impregnate the metal with a micro thin dry film . You can look them up on the web. I can tell you if you put it on gun metal you CAN'T put a finger print on it .

[Bill_Rights]

eagles, OK, thanks. I'll check it out.