Accuracy question

Flashpoint

Flashpoint

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I just acquired a Savage FV-SR 22lr that I believe should be capable of 1 moa, but aside from the random really good group here and there I'm getting about 2 moa out of it shooting what I believe should be capable ammo (Federal Automatch, CCI Subsonic, and various lots of CCI Standard Velocity). First, is it wise to expect 1 moa out of this rifle/ammo combination?

My main question though involves the guy behind the glass. I'm so glad I finally got (what I hope should be) an accurate 22lr to train with because I believe I am discovering things I didn't know. The main thing being it's much easier to see what is really going on without recoil throwing off my sight picture. This is what I think I've learned, you tell me if I'm right:

I used to think that barring other variables (assuming perfect rifle, ammo, no wind, etc.) that assuming the rifle was zeroed, the POI would be where the crosshairs were when the bullet left the bore. I've noticed though that when I screw up and know I pulled one off target the round will impact in line with the direction I pulled it but 2-4 times farther off than my POA at the time the rifle fired. So I think I'm actually slinging the bullet, imparting some off axis velocity to it. So, let's apply this thinking to my group sizes:

I'm shooting off a bipod with no rear bag, just my support hand back there adjusting for elevation, and although I'm on a stable platform, I'm far from rock solid. I've got a 1/4 to 1/2 moa wobble that is coming from me. I used to think this would only throw me off 1/4 to 1/2 moa, but now I'm thinking that wobble is slinging my bullets out farther than that.

So am I learning something or full of baloney?
 
I can't teach you any technique, that's for sure. Use the guy above for that. But trying to guess if you rig is accurate using good 22lr without having a stable platform seems pointless. If I wanted to see if my rifle was capable of 1moa I'd get that sucker loaded into a good stable rack, rig or bench rest fancy butt device. Shoot all my fancy ammo and see what the best group I can get is. That should be pretty close to the rifle's max capabilities. Then you can use a bipod and support hand and anything over your best rested group is about your level of user error. You are trying to calculate your part of the crime with no set point to start. It may be that rifle sucks and you are awesome. Or you suck and the rifles is awesome. Right now you have no clue about either one. Get a good baseline and then work on technique from there if tiny groups is your thing. Good luck.
 
I'm not asking for an analysis of my shooting technique or how to fix me, the gun or anything else. I'm simply asking if a certain amount of wobble causes groups to be larger than the wobble. It's a straightforward question.
 
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I have a FVSR so first off, how many rounds have you shot through it? It'll take 500+ for it to settle down. Second, what are you doing in cleaning? Some amount of lead deposited helps to maintain consistent accuracy so vigorous cleaning can be detrimental to accuracy. Third, what's your screw torque? The Savage MK series of 22lr can be sensitive to torque on the mounting pillars.

To further address the question, I guess maybe, if your wobble is in a certain direction and that round you're shooting is on the outside of the possible dimension of the group, think a double helping of wobble in the wrong way. More likely is the ambient conditions you're shooting in. If there's a possible intermittent draft between you and that 100yd target, it can move the group a bit as well. If the air is gusting a bit, I can see it causing what you've described and it wouldn't take much for a 22lr.
 
Folks over on rimfire central say that the factory synthetic stocks on those rifles are responsible for accuracy issues. I'm assuming that you're not seeing any issues from loose scope mount and/or rings.

American Rifleman tested out the FVSR with a variety of std and high velocity ammo and achieved groups ranging from .8 - 1.6". Best accuracy was with PMC match ammo coming in at .49". So, 2MOA group size that you're seeing doesn't seem out of line with their results at 50yds.

https://www.americanrifleman.org/articles/2014/4/30/savage-mark-ii-fv-sr/
 
Thanks for the informative gun-specific responses. Dave I just bought the gun, that was the first day shooting it. :) So yes it's nowhere near broken in yet if it takes 500 rounds to lay down enough fouling to be at it's best. Have not cleaned it at all. I'm aware of the fouling equilibrium thing, at least that's what this guy calls it (very informative series of vids on long range shooting).
It's funny though how you read these gun reviews and they get these awesome groups and you know they just got a brand new gun from the manufacturer.

Yes there was wind. Sometimes I waited, but I am an impatient soul so mostly I just threw caution to the, well, you know. Shooting low velocity ammo couldn't have helped in that regard (wind) either. It liked CCI SV the best.

I'm still curious about the answer to what should be a straightforward physics question though!
 
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Thanks for the link nbkky71, it looks like they didn't do any better than I did until they immobilized it in a sled, and that was with match ammo.
 
There were some guys over on rimfirecentral.com that have gone to great lengths to accurize their FVSR's. Replacing stocks, bedding the actions, etc. have gotten some folks into the 1/4" club. Worth browsing...
 
Flashpoint said:
I'm not asking for an analysis of my shooting technique or how to fix me, the gun or anything else. I'm simply asking if a certain amount of wobble causes groups to be larger than the wobble. It's a straightforward question.
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Ha, sorry. But 4 paragraphs for a straightforward question? :p
 
Flashpoint said:
Thanks for the informative gun-specific responses. Dave I just bought the gun, that was the first day shooting it. :) So yes it's nowhere near broken in yet if it takes 500 rounds to lay down enough fouling to be at it's best. Have not cleaned it at all. I'm aware of the fouling equilibrium thing, at least that's what this guy calls it (very informative series of vids on long range shooting).
It's funny though how you read these gun reviews and they get these awesome groups and you know they just got a brand new gun from the manufacturer.

Yes there was wind. Sometimes I waited, but I am an impatient soul so mostly I just threw caution to the, well, you know. Shooting low velocity ammo couldn't have helped in that regard (wind) either. It liked CCI SV the best.

I'm still curious about the answer to what should be a straightforward physics question though!
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Yes. If you are wobbling and causing some kind of non-straight line path the distance off center gets larger the farther you go. So at the muzzle your error might be 1/16". Stretched out to 50' that will be larger. And there are math formula's to figure it all out. If you knew the angle off center out of the muzzle you could figure outnhow far off you will be at a given distance.

Kinda why 1 moa at 1000' doesn't equal 1".
 
CZfool68 said:
Yes. If you are wobbling and causing some kind of non-straight line path the distance off center gets larger the farther you go. So at the muzzle your error might be 1/16". Stretched out to 50' that will be larger. And there are math formula's to figure it all out. If you knew the angle off center out of the muzzle you could figure outnhow far off you will be at a given distance.

Kinda why 1 moa at 1000' doesn't equal 1".
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I don't think you understand what I'm asking, which is partially why I took a while to try and explain it initially. This doesn't have anything to do with why 1 moa is 10" at 1000', or even why 1 moa at 100' doesn't always equate to 1 moa farther downrange. It has more to do with the velocity of the off axis movement of the bore at the time of firing. We're talking imparting an off axis velocity here, not just the angle of the bore off the path to the bullseye.

Picture swinging a rifle like a baseball bat and firing it in the middle of the swing. Is the bullet going to go straight where the rifle was pointed when it was fired? No. it will have an additional off bore axis velocity. My question is, is that off axis velocity imparted by the wobble enough to cause the group to widen appreciably, like 2-3 times greater than the angular error of the wobble itself?
 
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IMO you'd have have a pretty oversized chamber or barrel for what you are describing to make a difference. It is almost like putting slider spin on a baseball and the baseball has some movement. Possible, but I can't imagine that with any decent rifle it would add enough to make a difference. I also think you are overthinking this. But hey, maybe I'm the only one that likes to keep things simple.

Get a good rest and don't worry about. The more variables, the less accurate you'll be.
 
CZfool68 said:
I also think you are overthinking this. But hey, maybe I'm the only one that likes to keep things simple.

Get a good rest and don't worry about. The more variables, the less accurate you'll be.
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Well you could definitely be on to something there. :)
 
borrow a sled and clamp it down and then shoot a few groups with the different ammos you have..then try some eley or lapua see if there is a difference. I had read some thread about temp and barometric pressures and the velocities recommended to compensate for each. maybe on thewindisnotyourfriend.com or team40x.com
 
Or you could just lower your standards and expectations to my level. For my rimfires I am perfectly happy if they are minute of squirrel at 50 yards. Beyond that they are for fun and less expensive trigger time.
 
I've got a Savage 22 Mark II that will shoot cloverleaf 5-shot groups at 50 yards when I do my part. The gun is more accurate than I am, most of the time.

I use a front rest and a rear sandbag, and I use high-end premium ammo, like Lapua, RWS, Eley, etc. Standard velocity seems to work best.

When I have used a bipod, and high velocity ammo, my group size did increase some as well.

I recommend trying a solid rest if you can, and try some premium standard velocity ammo. CCI's would make a good starting point. Also check that your action screws are tight, and that the barrel is fully free floated. if there's pressure on the barrel anywhere, that could impact how the gun shoots.

Also, with 22's, you typically do not want to let the barrel cool much between shots, and you don't want to clean it too often. All the .22 benchrest guns I've shot did best when they were shot frequently and the bore cleaned no more than every 500-1000 rounds.

Outside of that, I couldn't really tell you anything without looking at your gun and watching you shoot. Hope some of that helps!
 
Untill you 500+ rounds through it and check the torque, I thinking it might be a loose screw behind the stock :D

My FVSR shoots 1moa with CCI SV regularly if ambient conditions are ok.
 
Although I appreciate all the advice this wasn't intended as a "help me or my gun shoot better" thread, it was a question about what happens when a bullet leaves the muzzle while the muzzle is moving. Should it impact at POI or farther out in the direction of the movement?

If anyone is interested though I did try some better glass and ammo and posted the results here: https://carolinafirearmsforum.com/index.php?threads/savage-mkii-fv-sr.6304/#post-107238
 
Flashpoint said:
Although I appreciate all the advice this wasn't intended as a "help me or my gun shoot better" thread, it was a question about what happens when a bullet leaves the muzzle while the muzzle is moving. Should it impact at POI or farther out in the direction of the movement?

If anyone is interested though I did try some better glass and ammo and posted the results here: https://carolinafirearmsforum.com/index.php?threads/savage-mkii-fv-sr.6304/#post-107238
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Well if nobody else will answer I'm happy to make something up.

Any lateral movement of the barrel will affect the bullet. The math is complicated because what you really do, or at least what I do, is strive to have predictable oscillation of the sight picture rather than trying to hold still. So as I swing back and forth the barrel goes from stopped to accelerating to the target to decelerating through the arc. If I release on target the barrel is at about max lateral velocity.

For grins let's say that the amplitude of my movement is 1moa, the frequency is .5 sec, that the target is at 100' and that the ammo velocity is 100'/sec. When I release the barrel is clipping along at 2moa/sec, the bullet takes .1 sec to get to target, so total error imparted by lateral movement is .2moa. Well, kinda, you see I always release when the barrel is moving left to right, and I strive to maintain consistent amplitude and frequency, so the error will be the same on all shots including my sighting in shots.

So, in theory yes in matters, but in practice I don't think it does.
 
Flashpoint said:
Although I appreciate all the advice this wasn't intended as a "help me or my gun shoot better" thread, it was a question about what happens when a bullet leaves the muzzle while the muzzle is moving. Should it impact at POI or farther out in the direction of the movement?

If anyone is interested though I did try some better glass and ammo and posted the results here: https://carolinafirearmsforum.com/index.php?threads/savage-mkii-fv-sr.6304/#post-107238
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I think your question is self answerable. Barrel harmonics form tight groups.

Poor POA in relation to POI equals very large groups compaired to harmonics alone.

John
 
Magdump said:
If I am understanding your question, this video should answer it:
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Hadn't seen that, but they are testing something different. They are looking at the path of the bullet and determining if it is straight or curved. Physics tells us with great certainty that it will be straight as there is no force exerted on the bullet after it leaves the barrel that would cause it to accelerate in any other direction. Well, they missed gravity which should have caused the bullet to curve downward, but that's not interesting TV. Anyway, back to the point, what the OP wants to know is if movement will cause the POI to be different that the POA at the time the bullet is fired, not if the bullet takes a straight or curved path.
 
JBoyette said:
I think your question is self answerable. Barrel harmonics form tight groups.

Poor POA in relation to POI equals very large groups compaired to harmonics alone.

John
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Barrel harmonics can and will have a Positive or Negative influence and definitely effect POI.
 
Flashpoint said:
Is the bullet going to go straight where the rifle was pointed when it was fired? No. it will have an additional off bore axis velocity.
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Sorry bud, you are wrong. Quit watching the movie "Wanted". The myth busters roundly debunked your theory.

If you swing your rifle like a bat and fire it the bullet will leave straight until gravity takes over....that being immediately. The only parabolic curve will be toward the earth imparted by gravity.

What you are suggesting is junk physics.
 
The Green Heron said:
Sorry bud, you are wrong. Quit watching the movie "Wanted". The myth busters roundly debunked your theory.

If you swing your rifle like a bat and fire it the bullet will leave straight until gravity takes over....that being immediately. The only parabolic curve will be toward the earth imparted by gravity.

What you are suggesting is junk physics.
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Came here to mention the movie Wanted

Was not disappointed
 
YeeHaa said:
???????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????

Barrel harmonics can and will have a Positive or Negative influence and definitely effect POI.
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True, but the level of affect is very small to poor aiming.
 
The Green Heron said:
Sorry bud, you are wrong. Quit watching the movie "Wanted". The myth busters roundly debunked your theory.

If you swing your rifle like a bat and fire it the bullet will leave straight until gravity takes over....that being immediately. The only parabolic curve will be toward the earth imparted by gravity.

What you are suggesting is junk physics.
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If you're going to argue with me at least make it in reference to something I said. :) I didn't say it would curve at all. I said it would fly straight but not aligned with the bore axis at the moment the bullet leaves the bore, it would have an additional horizontal velocity component. Feel free to prove me wrong, I'm here to learn. BTW I have never seen this movie or Mythbusters episode.
 
Wow. Wow. There is so much going on here I don't even know where to begin.

1) To address the point about a 'horizontal velocity component.' We need to understand a few things. First of all, IF it were true that your moving the barrel imparted acceleration on the bullet laterally, it would produce a curve, not a straight line. The acceleration produced by gravity results in a curve, and acceleration laterally (wind drift, etc.) produces a curve as well. There is not a scenario where the bullet could move off the bore axis without moving in a curve.

2) You are vastly overestimating the potential impact that the horizontal acceleration of the barrel could have on the vector of the bullet. The acceleration due to gravity is a much stronger acceleration that moving the barrel a bit to the side would be, and we see how far it takes for those effects to actually cause the bullet to drop a significant amount.

3) You are vastly overestimating your ability to 'call' where the impact of the shot should have been. A lot happens in that split second that you pull the trigger, and a lot of forces are imparted by your hand and arms to push or pull the shot. This is not happening off the bore axis, but is moving the actual bore itself. What is happening in your scenario is that you are actually moving the bore more than you think you are.

4) You are probably underestimating the amount of wobble that could be compounded from all the components of your shooting system. 1/4 MOA wobble would mean 1/400 of an inch at the rifle (roughly). That's an extremely tiny amount, probably close to being imperceptible. The fact that you can perceive the wobble means that it's probably a bit more than you are currently estimating.
 
np307 said:
1) To address the point about a 'horizontal velocity component.' We need to understand a few things. First of all, IF it were true that your moving the barrel imparted acceleration on the bullet laterally, it would produce a curve, not a straight line. The acceleration produced by gravity results in a curve, and acceleration laterally (wind drift, etc.) produces a curve as well. There is not a scenario where the bullet could move off the bore axis without moving in a curve.
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Not sure who you are addressing, but you have a teeny tiny problem with physics.

Gravity is a force that is exerted at all times on the bullet, so the bullet accelerates towards the ground which is why the path is curved.

Wind is a force that is exerted at all times on the bullet, so the bullet accelerates in the direction the wind is blowing so that path is also a curve.

Lateral force from the barrel is only exerted while the bullet is in contact with the barrel, so the bullet stops accelerating laterally once that contact is broken and bullet will travel in a straight line if there are no other forces acting upon it.

Hope that helps.
 
JimB said:
Not sure who you are addressing, but you have a teeny tiny problem with physics.

Gravity is a force that is exerted at all times on the bullet, so the bullet accelerates towards the ground which is why the path is curved.

Wind is a force that is exerted at all times on the bullet, so the bullet accelerates in the direction the wind is blowing so that path is also a curve.

Lateral force from the barrel is only exerted while the bullet is in contact with the barrel, so the bullet stops accelerating laterally once that contact is broken and bullet will travel in a straight line if there are no other forces acting upon it.

Hope that helps.
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No, wind is not constant at all times on the bullet unless you have the same exact wind speed and direction for muzzle to target. A bullet that leaves the barrel in no wind, but crosses through a section of 10 mph wind and then out of it before the target, will be affected with a curve and will not "auto adjust" onto a new vector. Inertia will continue to carry the projectile after the initial acceleration from wind, etc. Nothing wrong with my physics.
 
np307 said:
No, wind is not constant at all times on the bullet unless you have the same exact wind speed and direction for muzzle to target. A bullet that leaves the barrel in no wind, but crosses through a section of 10 mph wind and then out of it before the target, will be affected with a curve and will not "auto adjust" onto a new vector. Inertia will continue to carry the projectile after the initial acceleration from wind, etc. Nothing wrong with my physics.
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To be clear, I'm not suggesting that such a curve would be parabolic, but that the redirection of the vector would be some sort of curve.
 
np307 said:
To be clear, I'm not suggesting that such a curve would be parabolic, but that the redirection of the vector would be some sort of curve.
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When there is a force exerted on the bullet then the bullet accelerates in the direction of that force, when there is no force then the bullet maintains velocity and direction, i.e. it moves in a straight line.

Thanks for pointing out that wind changes.

Why did you put "auto adjust" in quotes, I never used such a term, don't recall you using such a term, what are you talking about? Did you maybe mean change direction?
 
JimB said:
When there is a force exerted on the bullet then the bullet accelerates in the direction of that force, when there is no force then the bullet maintains velocity and direction, i.e. it moves in a straight line.

Thanks for pointing out that wind changes.

Why did you put "auto adjust" in quotes, I never used such a term, don't recall you using such a term, what are you talking about? Did you maybe mean change direction?
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Sorry, that wasn't a reference to what you were saying, but the op's idea of what is going on.
 
Flashpoint said:
If you're going to argue with me at least make it in reference to something I said. :) I didn't say it would curve at all. I said it would fly straight but not aligned with the bore axis at the moment the bullet leaves the bore, it would have an additional horizontal velocity component. Feel free to prove me wrong, I'm here to learn. BTW I have never seen this movie or Mythbusters episode.
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IMG_20160530_133202750_optimized.jpg

Wow, ok, glad you cleared that up. So sorry I wandered in here.

Lemme just

Find the lightswitch and back the f#@& out of here before it rubs off on me.
 
JimB said:
Not sure who you are addressing, but you have a teeny tiny problem with physics.

Gravity is a force that is exerted at all times on the bullet, so the bullet accelerates towards the ground which is why the path is curved.

Wind is a force that is exerted at all times on the bullet, so the bullet accelerates in the direction the wind is blowing so that path is also a curve.

Lateral force from the barrel is only exerted while the bullet is in contact with the barrel, so the bullet stops accelerating laterally once that contact is broken and bullet will travel in a straight line if there are no other forces acting upon it.

Hope that helps.
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It appears you are wrong.
You have been warned.
 
billyh said:
So... back to the original post. Get a 6.5 based round because it's far superior than a .308 witch is leaps and bounds better than a .22
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6.5 curves less than .308 which curves less than .22. I thought that went without saying.
 
JimB said:
6.5 curves less than .308 which curves less than .22. I thought that went without saying.
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Take nothing for granted. The world is a lesser place in the vacuum of the absence of the expression of your knowledge. This is the grand premise of the internet after all...
 
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