Well, crap. WTF.

mr.orange

mr.orange

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Looking for some thoughts on what went wrong here...

Made up a new load for my 1972 Winchester Model 70 in 30.06. New Leupold VX-Freedom scope. Shooting with a bipod and sand bag rest, or a sled.

I went to the range a number of weeks ago with 5 test rounds of increasing charges (ie. 5 at 46.0 grains, 5 at 46.5 grains, 5 at 47.0 grains, etc.). Found that the rounds at 47.0 grains performed best with a group of about an inch, at 100 yards. Went home and made up 25 more...

Winchester brass
Winchester LR primers
IMR 4895 powder
180 grain Nosler Partition Spitzer, BC 0.474

The lightest of possible crimps was used. The bullet was seated to the max overall length.

Went back to the range and thought to sight in at 200, and started getting groups of 8-10 inches. After much cursing & confusion, I took it back to 100 yards and got groups of three quarters of an inch to one and a quarter inches....now I'm really confused. Why is the group tight at 100, but all over the map at 200, and back to tight at 100 again? Am I throwing curveballs and sliders here???

Weather was calm, with next to no wind, bright sunny morning with temps increasing from 15 to 20 degrees as the morning wore on.

Would appreciate some thoughts and suggestions from those who might have seen this behavior before, and could advise on maybe something I'm missing.

Thank you.
 
mr.orange said:
Looking for some thoughts on what went wrong here...

Made up a new load for my 1972 Winchester Model 70 in 30.06. New Leupold VX-Freedom scope. Shooting with a bipod and sand bag rest, or a sled.

I went to the range a number of weeks ago with 5 test rounds of increasing charges (ie. 5 at 46.0 grains, 5 at 46.5 grains, 5 at 47.0 grains, etc.). Found that the rounds at 47.0 grains performed best with a group of about an inch, at 100 yards. Went home and made up 25 more...

Winchester brass
Winchester LR primers
IMR 4895 powder
180 grain Nosler Partition Spitzer, BC 0.474

The lightest of possible crimps was used. The bullet was seated to the max overall length.

Went back to the range and thought to sight in at 200, and started getting groups of 8-10 inches. After much cursing & confusion, I took it back to 100 yards and got groups of three quarters of an inch to one and a quarter inches....now I'm really confused. Why is the group tight at 100, but all over the map at 200, and back to tight at 100 again? Am I throwing curveballs and sliders here???

Weather was calm, with next to no wind, bright sunny morning with temps increasing from 15 to 20 degrees as the morning wore on.

Would appreciate some thoughts and suggestions from those who might have seen this behavior before, and could advise on maybe something I'm missing.

Thank you.
Click to expand...

I'm not the most knowledgeable but I'm thinking paralax or something scope related.but there will be some astute people coming to help.
 
Yes, I'm thinking there's three options:

- operator error, but I think the bipod and sandbag, or sled would have eliminated most of that
- the scope
- mismatched rate of twist, velocity, and weight of bullet (approx 1:9.5, 2638 ft/sec, 180 grain nosler bullet). No evidence of keyholing or tumbling. Just wildly inaccurate.
 
Only speculating since I was not there. Assuming no mix up on the reloading bench, the following are all issues which I have experienced that have caused (or maybe caused because I don't know for sure) random fliers or more open groups:

Scope and rings: Rings torqued too tight stressing the scope? Are the rings not in line and not concentric, with an edge of a ring stressing a point on the scope tube?

Action screws: Check for torque. Sometimes action screws work loose causing random movement and fliers.

Stock barrel channel: Check with the 5 dollar bill for any stock contact with barrel. Can cause random fliers especially as barrel heats up.

You mentioned using a sled? As a beginner I bought a lead sled and used it at the range, thinking it would help to control variables. My benchrest friends mentioned to me that I would shoot better without the sled. They said it can interfere with recoil management, and can cause inconsistent muzzle jump. They also said it can be hard on the rifle and optic (depending on how weighted the sled is). Since then I have never used the sled, and now shoot only with a rear bag that allows for backward recoil movement. Never done a side by side test so can't confirm if it made a difference, but I trust my BR friend's advice.

Benches: was there any difference in the benches used? Our range has solid concrete benches that don't move, and old rickety wooden benches that move.

Eyes, target design, and parallax: Were the aiming points very small for both 100 and 200? My Leupold 3-9 scope has no parallax adjustment, and failing to check parallax before firing each shot is a cause of more open groups for me. A bigger aiming bull or diamond or cross or whatever it is at 200 can be fuzzier and cause me parallax errors because of lack of crisp small reference points to check parallax, especially if there is mirage that day. My older eyes are also no doubt allowing my reticle to wander more on a bigger aiming point without me realizing it. The old saying: "aim small miss small" is true for me. That target pattern aiming point chosen at 200 can make a big difference.

Just some thoughts, best of luck in solving the mystery.
 
Shooting a 9x scope at 2-300 yards is easier with a different target compared to what you can get away with at 100 yards.
Try a larger black square or diamond.
 
As I have written here, many times, 100 yards only proves the rifle will shoot at 100 yards. If you want 200 yard or 300 yard performance, do your development at that range.

The larger group is not related to twist. If it was a twist issue, you would not have good 100 yard groups. That twist will shoot a standard 220 gr bullet.

It is not the rifle (bedding). 100 performance proves that.

Is the big group tall and skinny? That would suggest a compensation issue (ammo). If flyers are also left and right, that suggests the scope.

If that scope does not have a parallax adjustment, it is set for around 125 yards. If you do not deal with the issue, you add about 4 inches to the group at 200 and about 6 inches at 300.

Put the rifle in the sled and look at something at 200 or 300 yards. Move your head around and watch the crosshair. The amount of movement you see across the target is what is added to your group.

Can you return the scope and get one with adjustable parallax?
 
Having issues with the same model of scope currently. Running out of elevation adjustment- at 25 yards 8" low. Proven combo- rifle and bases worked just fine with other scopes. 3 ring types, 2 standard, one Burris internally adjustable with 10 moa shims adjusted 10 up in front, 10 down in back. Thought that somehow it was installation issue, read, redo. Three times redone, not nearly the first or 30th scope/ring/bases I've installed successfully. Double checked base numbers for model compatibility etc. Called the experts at Leupold, said shimming of base or 20 moa rail may be needed. Maybe. But on a standard base at 25 yards initial sight in????
I optically re centered crosshairs, remount. No dice. Trying another scope next. If that works out, they can have it in for warranty. Frustrated with that Freedom scope. Keeping an eye on the thread to hear more about how your issues pan out with it.
 
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Shua said:
Having issues with the same model of scope currently. Running out of elevation adjustment- at 25 yards 8" low. Proven combo- rifle and bases worked just fine with other scopes. 3 ring types, 2 standard, one Burris internally adjustable with 10 moa shims adjusted 10 up in front, 10 down in back. Thought that somehow it was installation issue, read, redo. Three times redone, not nearly the first or 30th scope/ring/bases I've installed successfully. Double checked base numbers for model compatibility etc. Called the experts at Leupold, said shimming of base or 20 moa rail may be needed. Maybe. But on a standard base at 25 yards initial sight in????
I optically re centered crosshairs, remount. No dice. Trying another scope next. If that works out, they can have it in for warranty. Frustrated with that Freedom scope. Keeping an eye on the thread to hear more about how your issues pan out with it.
Click to expand...
Did you shim it backwards?
 
If you compare length

0.308 180.0 E-Tip™ 1.464
0.308 180.0 Partition (Litz) 1.188
0.308 180.0 Partition™ Protected Point 1.180
0.308 180.0 Partition™ Spitzer 1.260

your length of your bullet is 1.260

a combination of factors could be the problem
? length......
? twist rate
? velocity
? other
 
Ganderite said:
As I have written here, many times, 100 yards only proves the rifle will shoot at 100 yards. If you want 200 yard or 300 yard performance, do your development at that range.

The larger group is not related to twist. If it was a twist issue, you would not have good 100 yard groups. That twist will shoot a standard 220 gr bullet.

It is not the rifle (bedding). 100 performance proves that.

Is the big group tall and skinny? That would suggest a compensation issue (ammo). If flyers are also left and right, that suggests the scope.

If that scope does not have a parallax adjustment, it is set for around 125 yards. If you do not deal with the issue, you add about 4 inches to the group at 200 and about 6 inches at 300.

Put the rifle in the sled and look at something at 200 or 300 yards. Move your head around and watch the crosshair. The amount of movement you see across the target is what is added to your group.

Can you return the scope and get one with adjustable parallax?
Click to expand...

Best answer of all the comments. I would suggest you look at parallax also. A friend of mine could shoot 1" or smaller (much smaller) groups all day till he hit number 4 or 5 in the shoot string then he would kick a flyer... I watched him and what he did was reach up and grab his sling and pull down on it when he really wanted to get that last shot in there .. Some time the simplest things are the things that ruin your day.

So if you twisting your wrist or gripping the rifle harder /softer all these things will throw your groups, as for a lead sled save you money and your stock.
 
Ganderite said:
If the accuracy falls apart between the two distances it must be a stability issue of some kind, is the twist effective even if it’s correct? I have 2 rifles that do the same thing, one is a corroded bore 32 40 that shoots fine at 100 but all over at 200, the other a 357 that shoots well at 50 but bad at 100.
Click to expand...
 
Actually I had a third rifle that did the same thing it was a 303, and it turned out to be just dirty and very hard to clean
 
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