At a loss on how to fix.

[Kuyong_Chuin]

I have two different rifles I am having problems with that I am not sure how to go about fixing the problems. First is a Marlin Model 60 22 LR rifle, it had a broken trigger guard which I finally found a new one locally. I replaced the guard and found out I was still having some of the same problems I was having when I found out the guard was broke. Failure to fire reliably and failure to eject round when having to manually eject the failed to fire round causing it to jam unless you unload the rifle mag first. It has been cleaned and all the parts checked for broken pieces but can not find anything broken. Only problem found on the internal parts was the bolt return spring had a kink in it so I replaced the spring with a new one and still have the same problems. Any ideas on what is causing this rifle to fail?

The second rifle is my 7.62 x 54R M44 Carbine. My nephew, who is just out of the army, was here helping to sight in the rifle since I can not do so yet because of surgery on my arm. We set up 3 targets at one at each spot 35 yards, 100 yards and 292 yards. The target were the 35 yard near zero, the 292 far zero, and the 100 yard target was to be 3.04 inches high for max point blank range for the 150 grain bullet I would be using. We started off using the 180 grain S&B rounds hoping to get it close then to fine tune the rifle with the 150 grain PPU rounds. First shot fired at the 35 yard target hit 4.25 inches high. We let the barrel cool and adjusted the scope to what should have been 4.25 inches lower on the target. Second shot fired over the target. More adjusting and 3 more shots still shooting over the target. 100 yard target same thing gun was shooting high no matter how many clicks we tried. Far target it hit the ground two feet in front of the target. With only one hole in the first target and none in any of the others and only one round left from the box of 180's I measured the bullet and found out they are .308 bullets not .311. Measured the PPU rounds and they are the correct size and the first round of if hit the top of the 35 yard target, four rounds later all are still shooting over the targets. If the new scope is not bad what would be causing these round to shoot high all the time? I can not see the iron sights with this setup without removing the cheek rest which would make the scope almost useless. :banghead:

 

[Jim K]

The Marlin problem sounds like the extractor is not gripping the round tightly enough. Either there is dirt under the extractor (most likely) or the extractor or its spring is faulty.

On the rifle, how did you sight in the scope to begin with? Eyeball bore sighting or a bore sighter or what? Trying to sight in a newly installed scope by firing is mostly a waste of ammo.

Jim

 

[LAGS]

How is the bore and chamber on the M-44 ?
Plus what kind of scope & mount are you using?
Something has to be loose.
I have a whole collection of the Mosin Nagants, some with scopes, and lots without.
Plus, how heavy is your trigger pull, and is it consistant ?
Also, have you checked the headspace on the rifle ?

The M N's are good shooters, especially when you re-work certain parts

 

[Kuyong_Chuin]

The Marlin problem sounds like the extractor is not gripping the round tightly enough. Either there is dirt under the extractor (most likely) or the extractor or its spring is faulty.

On the rifle, how did you sight in the scope to begin with? Eyeball bore sighting or a bore sighter or what? Trying to sight in a newly installed scope by firing is mostly a waste of ammo.

Jim

On the Marlin it was cleaned very good but I might have missed some grit somewhere I'll take it apart and clean it again.

How is the bore and chamber on the M-44 ?
Plus what kind of scope & mount are you using?
Something has to be loose.
I have a whole collection of the Mosin Nagants, some with scopes, and lots without.
Plus, how heavy is your trigger pull, and is it consistant ?
Also, have you checked the headspace on the rifle ?

The M N's are good shooters, especially when you re-work certain parts

On the M44 I have found a few problems and fixed most of the ones I found after going over the gun again. The barrel has been counter bored and slugs .3115. The mount is a Brass Stacker Mount with an AIM 2 x 7 x 32 LER Scout scope. I removed my temporary home made cheek rest and removed the bolt was I could see down the bore this time so I would know what was going on. I clamped the rifle down so it wouldn't move and aligned the bore with the center of the target which was setup at 25 yards. Then I looked through the scope and it was way out. There was an adjustment on the mount to fix the up and down so it is now about right on that part. But the scope was not sitting straight on the rail and it was aiming so far to the left of the bore that it would miss the 12 inch target even after moving the clicks as far as it would go. After I clamped it down I noticed the rings had worked lose so that was another of the problems. I added a shim to the ring clamp which moved the point of aim to a point it looks like it might be getting close. I'll have to check it tomorrow, it started getting to dark to see today. Might have to add another shim. If the shims don't work I do not know what to do to fix the right and left POA so it is straight.

 

[LAGS]

@ K C
Remember if you are bore sighting at 25 yards, your center of your crosshairs will not be on the bullseye
The Vertical crosshair should line up with the bullseye, but because the scope is higher than the centerline of the barrel the Horizontal line will not be right on the bullseye.
the Horizontal line should be higher than the bullseye by the same measurement as the scope center is above the center of your bore.

 

[ngnrd]

...
the Horizontal line should be higher than the bullseye by the same measurement as the scope center is above the center of your bore.

What?? I don't think so. The bullet must be going UP when it leaves the barrel. If it's travelling parallel as it exits, it will only drop from there, and every shot will be low.

 

[LAGS]

@ ngnrd
The bullet comes out of the barrel in a straight line and travels pretty much in a straight line for almost a hundred yards. it is NOT going in an upward angle.
If line of flight, and line of sight are at the same point at 25 yards it is forming a triangle.
If you move the target to 100 yards, and the scope crosshairs are on the bullseye, the bullet flight because of the previous triangle you already set at 25 yards will mean the bullet will be flying Over the target at 100 yards.

The scope being set say 1.5" above the line of the bore ia what forms the triangle.
And at 25 yards the two angles are much steeper than the angles that are formed at 100 yards.
Draw a Scale graph and you will see what I mean.

Iron sights are much closer to the centerline of the bore, so no matter what distance you are shooting the line of sight is almost the same as line of bullet flight, untill you get to the point where the bullet starts to drop because of loss of volocity.
That is the distance where you have to raise your rear sight and compinsate for bullet drop by making the bullet go a little upward.
But in Big Bore rifles, that does not occur untill you are shooting past 100 yards like with a 30-06 0r .308.
But slower bullets like a .45/70 will start to drop at shorter distances.

 

[BBBBill]

Too many folks have seen those sketches in the military manuals showing the bullet trajectory appearing to climb like a plane when it leaves the barrel.

 

[carbine85]

You might want to consider getting rid of the Marlin 60 and get another. If the money and time isn't a problem then the challenge might be worth it. I think your problem is in the extractor.

I have a M44 with Mojo sights that I play around with. The .308 ammo doesn't shoot well at all. I have also concluded that the lighter ammo isn't the best choice. Mine prefer the heavier 180 - 184 grain .310 -.311 ammo. Longer bullets like the Russian Match ammo shoot well.
Sighting in at 35 yards is just wasting ammo. At 100 yards you should be +2", 200 yards is 0" and 300 yards is -10"
Another issue I have found with almost every Mosin is copper fouling. In some cases it's almost like copper plating.
A good trigger job goes a long way with these guns and very easy to do.
What type of scope mount are you using. My brother has tried the scout mounts with little success.

 

[LAGS]

@ Carbine85.
People Giving up on a gun that wont function right is how I aquire many of my guns at VERY GOOD prices.
And most of the time , I have the fix figured out before the money ever changes hands.
Just take some time, and learn how a gun functions, and it is all basic from there.
But if you cant find the problem, or fix it.
Why would you sell it and buy the same model gun ?

 

[Sam1911]

The bullet comes out of the barrel in a straight line and travels pretty much in a straight line for almost a hundred yards.

Well, not quite. An object accelerates as it falls, but it is falling immediately as soon as it leaves whatever is supporting it (in this case the barrel). The bullet doesn't go straight for 100 yards and THEN start to fall. What happens is that the longer it has to fall (the longer since it left the barrel, and hence the farther it is from the barrel) the faster it is falling. So it falls more inches down per yard of horizontal travel at around 100 yards than it did as it passed 25, and more inches down per yard of horizontal travel out near 500 yards than it did per yard of horizontal travel around the 100 yard mark.

Technically, this is right about 32 feet of fall per second, PER SECOND. That means as the bullet travels for one second, it falls 32 feet, and as it travels along for another second it falls an additional SIXTY FOUR feet (96' total fall so far), and so on.

Our bullets are arriving at our 100 yard target in (for a 3,000 fps cartridge) 1/10th of a second so the bullet is only going to fall some small fraction of that. (This is a related rate problem and the calculations are a little more complicated than they appear and are affected by a lot of real-world factors, but suffice to say the bullet only falls something like 10-30 inches in that first 100 yards and picks up the rest of the 32 feet of fall in whatever horizontal distance it is able to travel before 1 second is up.)

it is NOT going in an upward angle.

Well, yes, it had better be! If the bore is not inclined slightly upward then the bullet will simply fall away farther and farther away from your line of sight, faster and faster, each yard it travels away from the barrel.

In reality we incline the barrel's muzzle slightly. The bullet is fired UPWARD by just a little bit. It passes through the line of our sights once on the way downrange (crossing our scope's zero at, lets say 25 yards) and then passes the line of sights again on the way down (crossing the zero again at something like 100 yards).

Here's a pretty neatly drawn chart to show this effect:

(Read more at "About-Shooting.com" http://www.about-shooting.com/Trajectory_Tables)

As you can see, the barrel has been inclined to fire the bullet upward until it crosses the sight line at 25 yards ("25 yard zero"), and as the acceleration of gravity causes it to fall away from that original line of flight it will pass again through the scope's line of sight at 200 yards.

If line of flight, and line of sight are at the same point at 25 yards it is forming a triangle. If you move the target to 100 yards, and the scope crosshairs are on the bullseye, the bullet flight because of the previous triangle you already set at 25 yardswill mean the bullet will be flying Over the target at 100 yards.

Exactly right (sort of...the hypotenuse of that triangle is a bit concave because the flight path isn't a straight line, but nearly so). And that's fine. If you want it to hit at 100 yards, you set the scope's line of sight to line up with the bullet's path (which is inclined above the horizontal) at 100 yards. It will ALSO align with that roughly parabolic flight path at some other "node" or point, but you'll have to experiment to find out what distance that one is at.

The scope being set say 1.5" above the line of the bore ia what forms the triangle.

Not really. Even if the scope and the bore were exactly on the same elevation -- you were shooting THROUGH the scope -- you'd have to elevate the bore to launch the bullet on an upward path or you'd not hit much.

Iron sights are much closer to the centerline of the bore, so no matter what distance you are shooting the line of sight is almost the same as line of bullet flight, untill you get to the point where the bullet starts to drop because of loss of volocity.

That's a handy sort of rough approximation, but it isn't really right.
The bullet is ALWAYS dropping, the increasing speed of that drop just starts to matter more and more as the bullet gets farther and farther away. Even with iron sights, the line of the bore should be deflected a bit upward from the line of sights, because the line of FLIGHT is not ever, at all, a straight line.

Too many folks have seen those sketches in the military manuals showing the bullet trajectory appearing to climb like a plane when it leaves the barrel.

Probably so -- inaccurate drawings make these concepts a little hard to visualize.
1) If the drawing fails to illustrate that the bore IS inclined upward, folks could get the idea that somehow the bullet lifts off and rises on its own. When in reality it is launched down a bore in a straight line of departure and is always falling, but that line it was launched on isn't horizontal.

2) SCALE is a huge factor. We're trying to show perhaps a rise of 6" above the line of sight over the course of 200 yards. That's really hard to draw on paper....6" fits on your screen there, but 200 yards DOESN'T! So we scrunch up the horizontal axis until we can see the whole thing in a 12" wide image...but that makes it look like a rainbow instead of a very VERY gradual curve, and that sort of thing confuses people not used to working with scaled images.

 

[carbine85]

Why would you sell it and buy the same model gun ?

So that you have one that works properly and the Model 60 is a good .22.

 

[beag_nut]

To Sam1911:
An excellent explanation and description of what REALLY happens!!!
I was fortunate enough to be taught this at the age of nine, so to me it is second nature. For others, it must be learned nowadays.

 

[Sam1911]

Thanks... A much simpler explanation:

it is NOT going in an upward angle.

A bullet is like a football. Throw a football perfectly horizontally. It isn't going to get to your receiver, unless he's close and very short.

If he's the same height as you and he's 20 yards away, you'll launch that football on an elevated line of departure. Your "bore line" is pointing at Venus or a passing jetliner or something. Your "sight line" is aimed at him, horizontal with you. As you let go of the ball it starts falling. Because you threw it on an elevated line of departure, as it falls away from that original line it will eventually cross your sight line again, hopefully at whatever horizontal distance he happens to be standing.

Technically, it crossed your sight line twice, once on the way up (in this case right at your hands) and again at the receiver's distance.

Without elevating your "bore" you'd have just thrown it into the dirt 10 yards from your own feet.

The only difference between the football and the bullet is that the bullet is traveling so much faster that the horizontal scale of the rise and fall is stretched out enough to make it hard to understand what's really going on. Well, that and that the football won't kill him.

 

[LAGS]

@sam1911
Thank you for the graph.
It is exagerated but shows what I was talking about.
The triangulatin at 25 yards zero clearly shows the bullet will be passing over the target at 100 yards.
But if your bullet is hitting in the center of the Bullseye at 25 yards, and the crosshairs are set above the bullseye by the distance your scope is above your center of bore, @ the 25 yard distance, the bullet will hit at center if bullseye, when the crosshairs are put on the bullseye at 100 yards, or darn close depending on your rifles caliber.

 

[TNBilly]

Kuyong_Chuin

Failure to feed/stovepipe is probably the most common mod..60 problem... if you'll lock the action open and look in the ejection port you'll likely see the cause. Look carefully at the top of the feed block and you'll see what is actually the end of a spring sitting in a narrow groove. The spring is actually what ejects the round and if it's laying flat in the groove it'll do nothing. The spring should be angled up slightly, say between .090 and 1/8". 1/8" is perhaps a little high, it's a bit trial and error. If you bend it up too high (use a small screwdriver) the bolt will have trouble coming back into battery. A little here depends on the "vintage" of your rifle, the newer ones are made "slightly" different. There are other causes but this is the most common one!

 

[Sam1911]

The triangulatin at 25 yards zero clearly shows the bullet will be passing over the target at 100 yards.

Yes. Your bore is elevated to make the bullet pass through the target at 25 yards. At 100 yards it hasn't fallen far enough yet to be passing BACK through the line of sight. But out at 200 yards it has fallen far enough to be passing the scope's line of sight again. Hence two "nodes" where the arc of flight and line of sight intersect.

But if your bullet is hitting in the center of the Bullseye at 25 yards, and the crosshairs are set above the bullseye by the distance your scope is above your center of bore, @ the 25 yard distance, the bullet will hit at center if bullseye, when the crosshairs are put on the bullseye at 100 yards, or darn close depending on your rifles caliber.

I think I see what you're saying here, maybe.

Now you're lowering the line of inclination of the bore and adjusting the sights or scope so that the line of sight intersects the bullet's flight path at 100 yards from the muzzle. The initial offset of bore and scope is taken into account by your adjustments, but isn't the controlling factor. But that's just an arbitrary fixed number. It doesn't have anything directly to do with how far above the horizontal your bullet travels before passing the line of sight again as it falls.

Except to say that the more offset there is of the barrel below the bore, the farther away from you, horizontally, the bullet will have to travel on its arc before it intersects the line of sight for the first time, and of course, for the second time -- for any given sight setting.

 

[kwg020]

The older Marlin 60's have a history of having weak or worn out springs. It's my understanding that Marlin makes a new spring kit. You will have to contact them to get the kit. An other issue with the Marlins is they don't like cheap ammo. Get a better grade of ammo. I suggest Winchester Super X's, CCI Mini Mags or the CCI Stingers. Stay away from the bulk pack ammo. If this does not fix it, then consider the spring replacement. kwg

 

[LAGS]

@ Sam1911
I bore or laser bore sight my rifles the way I described at 25 yards an the crosshairs above the bullseye.
When I take them to the range for sighting in they are always ON Paper, and most times in the bullseye, at 100 yards.
I also set my scope to Zero/ Zero adjustments on a set of " V " blocks, and then mount the scope and bore sight it.
I shim or machine the mount or rings so my rifles are set with the scope still at the Zero /Zero setting, and they are bore sighted at 25 yards and on target at 100 yards.
That way I have Full adjustment of the scope if I need it.
I help friends set their rifles up the same way so they can have a Zero / Zero scope on paper at 300 or 400 yards if that is what they shoot at.
Then they Never run out of adjustment when the move to 500 to 800 yards.

I just really hate it when I am trying to help a friend before the season sight in their rifle, and the scope is cranked all the way in any direction just to get it on paper.

 

[Sam1911]

Absolutely, that all sounds right, and a pretty smart way to go. The only thing I'm not sure we're clear on is that the bullet is still being launched on an angle upward so that it will intersect the line of sight -- twice -- as it is falling away from the line of departure. The chart I linked shows that pretty clearly.

If you could see your boresight line out to infinity, it would line up with the crosshairs at whatever distance you're setting the scope to. (A bit high at 25 yards, I think?)

But your boresight line would then continue on, DIVERGING from the scope's line of sight -- heading up. However the bullet will be falling away from the boresight line so that it will cross the sight line again somewhere farther down range. If the velocity matches that in the chart I posted, that will be at 200 yards.

 

[LAGS]

The Bore sighter laser dot is on center of target at 25 yards, and if my scope is mounted 1.5 " above the bore, then the scope crosshair horizontal line is on the 25 yard target 1.5" above the laser dot.
That means the line of bore or start of the bullet flight are basicly Parallel to line of sight.
My .308 or M N's do not drop much at 100 yards.
So at that distance, line of sight, and line of flight are almost the same, but in a very slight line of inclanation to triangulate to 100 yards.
But if the bullet and crosshairs are both in center of bullseye at 100 yards, the line of sight will be higher than line of bullet path at 25 yards with the scope mounted 1.5" above the bore.

 

[45_auto]

Technically, this is right about 32 feet of fall per second, PER SECOND. That means as the bullet travels for one second, it falls 32 feet, and as it travels along for another second it falls an additional SIXTY FOUR feet (96' total fall so far), and so on.

Close, but not quite the way it works.

For second number one, the bullet (or any other object) initially starts with a downward velocity of 0 FPS. It accelerates downward at 32 FPS per second, so at the end of the first second it is falling at 32 FPS. But it started at 0 FPS, so it's average velocity (velocity and acceleration ARE NOT the same thing) over the first second is 16 FPS. So it falls 16 feet the first second.

For second number two, the initial velocity is 32 FPS. It is still accelerating at 32 FPS per second, so at the end of second number two it has a velocity of 64 FPS. It's average velocity for second number two is 48 FPS, so it falls 48 feet during second number two.

Total vertical drop at the end of two seconds would be 16 feet from second #1 plus 48 feet from second #2 for a total of 64 feet at the end of second #2.

For second #3, initial velocity = 64 FPS, final velocity = 96 FPS. Distance dropped during second #3 would be 80 feet. Total drop after 3 seconds would be 64 + 80 = 144 feet.

Easiest way to calculate it is that the total distance the object falls is proportional to the square of the time unit.

For example, it falls 16 feet in second #1. That means that 1 x 1 x 16 = 16 feet total drop. Velocity at the end of second #1 is 1 x 32 = 32 FPS.

In second #2, total distance dropped will be 2 x 2 x 16 = 64 feet total drop. Velocity at the end of second #2 is 2 x 32 = 64 FPS.

Second #3 = 3 x 3 x 16 = 144 feet total drop. Velocity at the end of second #3 is 3 x 32 = 96 FPS.

Second #4 = 4 x 4 x 16 = 256 feet total drop. Velocity at the end of second #4 is 4 x 32 = 128 FPS.

Second #5 = 5 x 5 x 16 = 400 feet total drop. Velocity at the end of second #5 is 5 x 32 = 160 FPS.

Etc, etc.

 

[Sam1911]

Bah, numbers!



Not going to do the math to double check all that, so I'll just say "thanks!"

 

[lathedog]

Kuyong_Chuin, did you perhaps adjust the scope in the wrong direction? It sounds like you were high at 35yd, then after adjustment went off the top of the paper.

All the rest of this is interesting, but you should be able to boresight and be on paper at 35yd.

I would go back over my entire setup. Check screw tension, then adjust the scope back to mechanical center for all adjustments. Then I would boresight. You do not need a laser to do this, just clamp the rifle really well and look thru the receiver and thru the barrel at some object. Then adjust the scope to the same point as you see thru the barrel. Then go attempt more shots.

The picture in post #11 is accurate (a similar graph is in every beginning physics book ever printed) but remember it is an example, and every load will have a different curve. Please do not get overly focused on this as it is not a prerequisite to sighting in a rifle.

 

[Kuyong_Chuin]

Kuyong_Chuin, did you perhaps adjust the scope in the wrong direction? It sounds like you were high at 35yd, then after adjustment went off the top of the paper.

All the rest of this is interesting, but you should be able to boresight and be on paper at 35yd.

I would go back over my entire setup. Check screw tension, then adjust the scope back to mechanical center for all adjustments. Then I would boresight. You do not need a laser to do this, just clamp the rifle really well and look thru the receiver and thru the barrel at some object. Then adjust the scope to the same point as you see thru the barrel. Then go attempt more shots.

The picture in post #11 is accurate (a similar graph is in every beginning physics book ever printed) but remember it is an example, and every load will have a different curve. Please do not get overly focused on this as it is not a prerequisite to sighting in a rifle.

This is what I did after I started having the problems. No I am not turning it the wrong way. I did find the ring screws had loosened up so I retightened them up this time with a screw driver not my fingers. While looking through the barrel with it locked down and set to the center of my target I could not get the cross hair to go far enough to line up. With it turned all the way as far as it will go down it was still over a foot and a half high. If I measured right with the tools I had available on hand, from the center of the bore to the center of the scope is 2.25 inches over the barrel. I found an adjustment on the front of the Brass Stacked that allowed me to bring the front of the scope down to the point I have room to adjust it now. Added a shim to the rings to move it over so it will line up right and left but since it was raining this weekend and I was tied up with doctors appointments allday today I have not had the chance to see if the shim I added will move it enough yet or not. The settings on the scope is as far as it will go right now. For the bullet I am using to hunt with the bc is 0.354 the fps advertised is 2840 out of a 24 inch barrel but the M44 has a 20 inch barrel rounded of course. Using a drag function of G5 and an eight inch kill zone I should be setting the rifle up for a 33 yard near zero and a far zero of 280 yards. That would put the bullet at 3.08 inches high at 100 yards for a MPBR of 328 yards. If the shim I am using doesn't work I guess I am going to have to have the rings modified somehow to line up right.

On the Marlin it ejects fine when it actually fire's the round. It just doesn't eject manually. Probably have to find a good local gunsmith that has a firing range at his location to fix the problem. I do not want to get rid of this rifle though I might buy another rifle to use and still get this one fixed because the rifle was given to me by my granddad before he died to replace the one that was stolen years ago.