Hey folks, i have recently purchased and set up a Savage Model 10PC .308 for some longer range plinking. With help from the great folks on here, i've been able to extend my shooting abillities to upwards of 600 yards and a bit. So, my question is, at 600 yards i'm consistently a little to the right, but at 100 yards my gun is absolutely dead nuts. I always sight in 1" high at 100 yards, and perfectly above the bullseye. So, could it be that i'm canting the rifle one way or another, or is this spindrift (i doubt it for these ranges), or do i just need more experience reading wind? The days i shoot these are typically mild when speaking of the wind. I know the wind has a huge effect on bullet path at extended ranges, i just wanted to get some ideas and information. Thanks in advance. hvychev77
.308 @ 600 yards help
- Thread starter hvychev77
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Spin drift at 600 yards will be a factor, and is .4MOA(2.4") to the right with my 308 shooting 175 SMK's at 2600 FPS. I would recommend you install a scope level, and perform a 100 yard tall target check on your rifles/scope set-up, if you haven't already done so. This would assure that your rig is plum and that you are not canting your rifle.
Thanks for the response. I do have a scope level, i just haven't put it on as of yet. I'm sure this will no doubt help. How do you obtain the spin drift data that you shared with me. I see where it would be around 2.4" at 600 yards, but i do not know how you calculated this? I'm assuming this would just be part of a normal ballistic calculator output? I have been using JBM Ballistics as well as G7 thus far with good results.
Also, you stated to do a 100 yard "tall" target. Now, forgive my ignorance as i'm just getting started here, but what would be the purpose of a tall 100 yard target? Would this be for adjusting for a longer shot to see where i visually hit?
Thanks again for the response.
hvychev77
Also, you stated to do a 100 yard "tall" target. Now, forgive my ignorance as i'm just getting started here, but what would be the purpose of a tall 100 yard target? Would this be for adjusting for a longer shot to see where i visually hit?
Thanks again for the response.
hvychev77
I use Shooter with spin drift enabled. If you enter a 0 wind, your windage in the ballistic data will reflect spin drift at a given range. Not sure about the programs you are using.
The purpose of the tall target test is to insure that your scope is mounted plum with your rifle. At 100 yards draw a vertical line using a weighted string to make sure its at 90 degrees. Making sure that your rifle is level fire groups at zero, and with a 20 MOA elevation using your turrets (or calibrated retical if you use this approach instead of turning turrets). If the two groups are on the plum line your set up is properly aligned. You can also, at the same time, measure and confirm you turret accuracy knowing your exact distance of 100 yards, and measuring between the actual impact point of the two groups against your turret adjustments. I do this when setting up all my long range rigs, and faithfully, and use a scope level.
gohring3006
Well-Known Member
I had this same problem and it was scope cant, I dialed mine in at the range I loosened my rings a and rotated my scope till the reticle was dialed in. Keep in mind that it doesn't take much rotation. I could barely see that I rotated it and it made a big difference.clockwise will shift the impact right.
snowpro440
Well-Known Member
+1 Exactly what Greyfox said...Scope Level is very important.
Awesome!! Thanks for the good info. everyone. Now i'm pointed in the right direction and know what to do. I hope this will be an easy fix.
One more question, how would one of the Wheeler brand scope leveling tools assist in making sure that I have my rig set up correctly? They're not that expensive and am just curious as to whether or not it's worth it or would be beneficial? Thanks again.
One more question, how would one of the Wheeler brand scope leveling tools assist in making sure that I have my rig set up correctly? They're not that expensive and am just curious as to whether or not it's worth it or would be beneficial? Thanks again.
snowpro440
Well-Known Member
Wheeler , LEVEL LEVEL LEVEL .........Yes I use mine often , Level your target with a level then I level my rest and bottom of my gun stock then the action then the scope crosshairs on the target, If all is level then your good to go.....
The Wheeler is a great investment. Using it when initially setting up my scope on the bench, my last four long range rigs were lined up perfectly when I did my live fire, tall target test and did not require additional adjustment.
Alright, i just purchased one from Amazon. Thanks for all the help guys. i'll have to make it a point to report back with my outcome. Bare with me though, i got a couple of young 'ens in the house that don't share a lot of free time for daddy!! Thanks again guys. Cheers. hvychev77
just wanted to say thanks for the help on my issue. I did use the Wheeler leveling system and it worked like a freakin' charm!! I shot a tall target at 100 yards after my zero was re-established from leveling everything out. I moved up 15 MOA and it was dead nuts. So, out to 365 yards, then out to 625 yards. With the exception of the wind, it was a major improvement from where i was before. So, all that to say thanks to everyone who provided feedback. What an awesome place for knowledge and help. Cheers.
Unofficial Gun Addict (UGA)
Well-Known Member
Ok guys... Sold me on the wheeler. Never used one, but for 17 bucks, seems like it's worth the peace of mind! I've got 8 different scopes that I move from rifle to rifle via quick release mounts and picatinny rails. This might be a good way to confirm that things stay level when moving from one gun to the next.
Thanks for the great post and info on the wheeler.
Thanks for the great post and info on the wheeler.
WildRose
Well-Known Member
Don't be surprised when you find out they don't. There are little eccentricities in the milling of every receiver. Some will really surprise you how far off they are.
When mounting rails I knew were perfectly straight I've had them visibly bow requiring a good bit of work and devcon to get exactly right.
Well this is a long shot but it can effect the over all. Have someone check to see if the bore is concentric to the barrel, it would and won't be the first or last barrel, if it is out; to slip by the inspectors. Just a thought.
Cheer's
436
Cheer's
436
