Spin drift seems excessive

[XBBR Shooter]

One thing you could look at is bullet holes shot on good quality white target paper at 100 yards. Look to see if the hole is perfectly round,, or is it slightly egg shaped horizontally.

It is possible that the bullet is traveling with the nose slightly to the right, the bullet may be stabilized and a sleep.

This is what I think the guys talking about the slightly curved barrel theory mean.

If this is the case, you will have to have a smith mark the barrel and clock it straight up then run a reamer in and set the barrel back a smidge. I have lots of Savage barrels for 2 actions and never have seen this issue.

Myself I would mark the end of the right side of the barrel near the muzzle and play with head space to see if it can be clocked up or down. It shouldn't effect head space a whole lot but it will. I set my head space up snug to new Lapua brass, and there seems to be some lee way with head space tolerances.

I think this is pure, unjustified silliness - bullets do NOT turn sideways and go to sleep - they come out of the barrel on axis, and stay that way, unless an external force acts on them. To do otherwise would be in total opposition to Issac Newton's 2nd law of motion.... which (in 328) years, has NEVER been found wrong.

 

[expiper]

I time all my bbls either left or right to help with the crosswind,,,,Roger

 

[STOMP442]

Ok guys I think we have this figured out. Cant was the issue. Turns out that although the scope is leveled properly while shouldering the rifle in the bag the wife was in fact tilting the rifle to make it comfortable to her and to me as well sometimes as I would also experience the drift at range. At 100 though I never seemed to have the problem. I think the varying heights of the benches at our range was messing with our ability to get comfortable in the rest and our shooting position. I borrowed a level from a buddy to install on the scope while we shot and made sure to keep it perfectly level during our course of fire and that seemed to improve things a lot. Thank you all for the input.

 

[XBBR Shooter]

Ok guys I think we have this figured out. Cant was the issue.

I have long felt that if you are shooting "long", whether on paper or beasties, and your gun is nnot equiped with a well set up bubble, you were just kidding around.

Bubbles are your friend. Get a bubble, or go home

 

[DanSavage]

I think this is pure, unjustified silliness - bullets do NOT turn sideways and go to sleep - they come out of the barrel on axis, and stay that way, unless an external force acts on them. To do otherwise would be in total opposition to Issac Newton's 2nd law of motion.... which (in 328) years, has NEVER been found wrong.

Well, I'm glad the problem is solved!

I got the silly idea from my experience throwing football. I can throw a stabilized perfect spiral with the ball's nose pointing at 45 degree to the right. The football will initially head straight toward the target for about 5 yards then it will start veering to the right maybe a foot off target. After about 30 yards the ball has straightened and is still stabilized. The force off the wind on a coned object while spinning will straighten after a given time.

I guess I'll call it Wilson's theory lol,, actually not a theory but a fact! if anyone is interested I could make a video clip!

 

[DanSavage]

I do get your point xbbr, a bullet can't come out of the bore side ways.

 

[walt willis]

I have built a 6mmBR for the wife on a Savage 11 action with a 26" Mcgowen 8 twist varmint contour barrel. The action is bedded in a Bobby Hart Bench Rest stock. She is running 105gr Berger hunting VLDs pushed by 29.0gr of H4895 in Norma cases and CCI small rifle primers at 2855 fps. Accuracy is excellent holding high .2's low 3's for five shots at 100 and 2-3" groups at 600. She uses this to compete in our local Prairie dog matches and she does very well even shooting perfect 10 for 10 scores on more than one occasion. She is a better shooter than me for sure. The problem we are having is there seems to be excessive spin drift beyond 200 meters. She can be zeroed at 200 and on a calm day she will impact about 2" right at 300 meters 4" right at 400 meters and 6" at 500 meters. I understand there may be wind components we may not be reading at various ranges but it is consistently running to the right beyond 200 meters on any given day. If she has a 5mph left wind she can hold center target and hit every target no problems. I am trying to figure out what the problem could be and any help would be appreciated. I am thinking of trying a different bulllet but I really do not want to give up the BC the Berger provides.

The scope she is running is a Leupold VXIII 6.5-20x50 mounted in lapped Talley rings. I have run the tall box test and checked for scope cant and the scope seems to track and function fine. I just don't know why this rifle wants to run to the right and spin drift seems to be the only logical explanation I can come up with but it seems excessive. Any help would be appreciated.

Have you tried more then one FPS load to see if the resident frequency can be improved?

 

[Dgd6mm]

I have long felt that if you are shooting "long", whether on paper or beasties, and your gun is nnot equiped with a well set up bubble, you were just kidding around.

Bubbles are your friend. Get a bubble, or go home


I took my .300 Lapua to Manatee. This is the first time I ever showed up and shot the 1000 yard 8" steel plate match. No bubble level. I was told in not a so much of a nice way by Mitt and some buddies that I could not be competitive without a bubble level. I shot 2 club records that day, took the cash and the trophy. When Mitt came over and shook my hand he said, nice shooting, even if you didn't have a level. My good shooters buddy Jim Carr aka Teele1 responded with, be didn't need one to beat you today.... Love this story. All kidding aside, I have used a bubble level on all my competition rifles ever since. I know without any doubt they have helped my score and made me a better shooter.

 

[XBBR Shooter]

Well, I'm glad the problem is solved!

I got the silly idea from my experience throwing football. I can throw a stabilized perfect spiral with the ball's nose pointing at 45 degree to the right. The football will initially head straight toward the target for about 5 yards then it will start veering to the right maybe a foot off target. After about 30 yards the ball has straightened and is still stabilized. The force off the wind on a coned object while spinning will straighten after a given time.

I guess I'll call it Wilson's theory lol,, actually not a theory but a fact! if anyone is interested I could make a video clip!

Bullets and footballs have less than nothing in common. "Coned" bullets (a misleading term, they do not cone) will not find it's way back to it''s original axis - it goes into "precession" which is a degenerating spiral... there is no way back.

 

[STOMP442]

I have long felt that if you are shooting "long", whether on paper or beasties, and your gun is nnot equiped with a well set up bubble, you were just kidding around.

Bubbles are your friend. Get a bubble, or go home

Well I shoot long range a lot and have killed at very long range more than once and have never used a bubble. This is the only rifle I have ever encountered this problem with.

 

[savagedasher]

Well I shoot long range a lot and have killed at very long range more than once and have never used a bubble. This is the only rifle I have ever encountered this problem with.

As long as the cant is the same every time and the scope is is adjusted for that yartage the bullet traveling the same speed the impact should be the same if conditions don't change. Larry

 

[Eddie Harren]

As long as the cant is the same every time and the scope is is adjusted for that yartage the bullet traveling the same speed the impact should be the same if conditions don't change. Larry

Does it matter if the yartage changes?

 

[savagedasher]

Does it matter if the yartage changes?

A bullet going vertically no . A bullet horizontal yes . Larry

 

[Eddie Harren]

Hee, Hee, Hee!