Ordering a CDS for 308

[Duckslayer89]

Trying to figure out what my muzzle velocity is on a 22 inch barrel with 308 nosler 165 grain accubonds. I can't find on noslers website what inch barrel they get their ballistics from. I have a feeling it's 24 and mine is only 22. Kimber mountain ascent. Any help appreciated

[Blacklab]

To get the full benefits of a CDS, you'll need to chronograph your loads.

[Duckslayer89]

Id like to try to get away without having to purchase one but that would be the best idea. Anyone else with a Mountain Ascent in 308 that shoots 165 factory accubonds ?

[Taco280AI]

Don't get the dial without knowing what your rifle is shooting at.

[Duckslayer89]

Don't get the dial without knowing what your rifle is shooting at.

So you wouldn't go by the Nosler ballistics for the accubonds from factory

[Taco280AI]

I've chrono'd Nosler ammo from my 280AI and would say no. Of three different factory loads of theirs one was about 24fps off. Not a big deal. Another was over 100fps slower than advertised and the third was well over 200fps slower. You just never know until you shoot it through your rifle and note the temp conditions when doing so.

[Duckslayer89]

I've chrono'd Nosler ammo from my 280AI and would say no. Of three different factory loads of theirs one was about 24fps off. Not a big deal. Another was over 100fps slower than advertised and the third was well over 200fps slower. You just never know until you shoot it through your rifle and note the temp conditions when doing so.

What kind of chronograph are you using? Thanks for the heads up sounds like it could be a big difference

[hogslayer]

I have 2 chronographs if you want to come shoot through one or borrow it for the day.  I wouldn't chance it with getting a CDS.  All the factory ammo i have shot was less than advertised on the box by quite a bit with the same barrel length.  Other way to do it would be take the fps marked on the box and enter your info into a ballistic app.  then go out and shoot at 300 yards and 600 yards and measure your drop.  Then you can adjust the fps in the app until it matches the real world drop. 

[b23]

The majority of factory centerfire rifle ammo, regardless of who's it was, that I've chrono'd has been substantially slower (100-200fps) than was advertised on the box with Nosler being one of the worst.  Doesn't mean it shoots bad but never go off of what the box says for velocity.  Rimfire ammo, surprisingly, is typically pretty close to advertised.

[Magnum_Willys]

Looking at their loading data kinda makes you suspect their 2800 fps for factory loads might be a little high.....

[Bob33]

To take advantage of a CDS dial you need accurate inputs of the variables, including velocity. The best way is to shoot several rounds over a chronograph.  You can't trust factory published data to be accurate enough because every gun and barrel may produce different results.

If you don't have access to a chronograph, you can get a pretty accurate estimate of the velocity by reverse computing it with ballistics software. Shoot the load at 100 yards, measure the vertical distance from point of aim, and then repeat at progressively longer distances. If you can shoot at 400 yards or longer, you should be able to compute the velocity fairly close by playing around with the velocity in the software until the drop results match your actual results.

A chronograph is really the best way. Also remember that air pressure as estimated by altitude, and ambient temperature affect bullet drop and that data will need to be provided for the dial. If you can do your velocity testing in conditions close to those where you hunt, it will help.

[Duckslayer89]

Ended up buying a chronograph today and a bunch of other stuff. Wheeler FAT WRENCH, P3 gun vise, competition electrics  Pro-chronograph, wheeler professional level system, and new talley lightweight rings just because. Going to do everything right and get that CDS dialed in perfect. Can't wait. Thanks for everyone who offered to let me borrow everything I just figured I should finally own my own

[Magnum_Willys]

    I dialed a one-shot elk at 460 yards this year and buddy did the same at 660 yards on a 330 class bull.  Both leupold CDS.   System works ! 

[Taco280AI]

I didn't do the custom dial but do have the standard MOA dial and love it. I might hunt anywhere from 8500 feet to 12,500 so have multiple charts to look at if needed

[wsmnut]

Ended up buying a chronograph today and a bunch of other stuff. Wheeler FAT WRENCH, P3 gun vise, competition electrics  Pro-chronograph, wheeler professional level system, and new talley lightweight rings just because. Going to do everything right and get that CDS dialed in perfect. Can't wait. Thanks for everyone who offered to let me borrow everything I just figured I should finally own my own

You'll be really glad you did that.  Those dials are amazing.  I've got two, and just put one on my wife's rifle.  Headed out this morning for testing!
I have one on a 300 WSI that put a rag horn bull in the freezer at 452 yards!  It's great fun to get out and start testing them at longer ranges.  Enjoy!

[Duckslayer89]

Ended up buying a chronograph today and a bunch of other stuff. Wheeler FAT WRENCH, P3 gun vise, competition electrics  Pro-chronograph, wheeler professional level system, and new talley lightweight rings just because. Going to do everything right and get that CDS dialed in perfect. Can't wait. Thanks for everyone who offered to let me borrow everything I just figured I should finally own my own

You'll be really glad you did that.  Those dials are amazing.  I've got two, and just put one on my wife's rifle.  Headed out this morning for testing!
I have one on a 300 WSI that put a rag horn bull in the freezer at 452 yards!  It's great fun to get out and start testing them at longer ranges.  Enjoy!

That's sweet dude let us know how it works! I'm stoked to have the capabilitys of the longer shots. The way I hunt I usually never shoot at anything over 150-200 yards but I want the capability. Plus I like to shoot so it will be fun to practice. When leveling the scope I'm thinking about hanging a string from the ceiling and lining the vertical line of the cross hairs instead of using a bubble level. Any opinions on this?

[CAMPMEAT]

My 20 inch was right at 2750fps 168 Berger VLD handloads.

[Blacklab]

Ended up buying a chronograph today and a bunch of other stuff. Wheeler FAT WRENCH, P3 gun vise, competition electrics  Pro-chronograph, wheeler professional level system, and new talley lightweight rings just because. Going to do everything right and get that CDS dialed in perfect. Can't wait. Thanks for everyone who offered to let me borrow everything I just figured I should finally own my own

  as said b4 you'll be glad you did  Having real number readings is the "start" to long range 

[hogslayer]

I just picked up a VX6 and will be ordering a CDS soon.  I am going to see if they can/will make a dial for MOA on the bottom and custom dial on top with numbers.  My hunting areas and conditions change so much that a CDS dial can become not useful.  From playing around with some numbers on my app, it seems that 500 and under stays pretty consistent in different elevations and temps.  Thought is that 500 and under could be a quick range dial send.  Anything over that i should have time to look at dial chart.

[Magnum_Willys]

I just picked up a VX6 and will be ordering a CDS soon.  I am going to see if they can/will make a dial for MOA on the bottom and custom dial on top with numbers.  My hunting areas and conditions change so much that a CDS dial can become not useful.  From playing around with some numbers on my app, it seems that 500 and under stays pretty consistent in different elevations and temps.  Thought is that 500 and under could be a quick range dial send.  Anything over that i should have time to look at dial chart.

http://kentonindustries.com/custom-turrets/leupold

[Duckslayer89]

did any of you have a scope that wasn't set up for a CDS dial and you added one later? Just seems like the 3 set screws are just putting pressure on the dial inside the scope caps what's keeping it from slipping? Would make sense if they had grooves or something to screw into

[Duckslayer89]

I have 2 chronographs if you want to come shoot through one or borrow it for the day.  I wouldn't chance it with getting a CDS.  All the factory ammo i have shot was less than advertised on the box by quite a bit with the same barrel length.  Other way to do it would be take the fps marked on the box and enter your info into a ballistic app.  then go out and shoot at 300 yards and 600 yards and measure your drop.  Then you can adjust the fps in the app until it matches the real world drop.

Thanks for the offer on the chronograph man! I ended up picking one up. Prochron I believe it's called

[dscubame]

I am excited for you.  I went through all what your describing last year and had a CDS made.  I had a blast doing it. 

Then got to elk season and ended up with a 50 yard shot to the head in timber with the 30-378.  Still laughing about it.  Hope to knock one down next year at some distance anyway.

[baker5150]

I am excited for you.  I went through all what your describing last year and had a CDS made.  I had a blast doing it. 

Then got to elk season and ended up with a 50 yard shot to the head in timber with the 30-378.  Still laughing about it.  Hope to knock one down next year at some distance anyway.

Thanks dude I did 2 rifles today, then broke my T10 bit on the third gun removing the scope rings from my mini 30. Can't believe ruger uses a T10 bit on the scope ring screws. Ridiculous. Talley uses a T15 bit. Much stronger and more realistic. I went and got a forged T10 bit from Milwaukee tools tonight going to try again in the morning when I'm home. I talked to leupold, looks like I have to send my Vari X3 in to have the CDS system installed. 90 bucks for the elevation install and 60 for custom dial. Hope it doesn't mess with my scope but those guys are professionals. They want to know height of the bore to scope length? Not sure why

I had to send mine in as well.  They did a perfect job, and did a full "tune up" while it was there.  Couldn't be happier, took about 2 weeks.  Maybe 2 1/2.

[Duckslayer89]

I am excited for you.  I went through all what your describing last year and had a CDS made.  I had a blast doing it. 

Then got to elk season and ended up with a 50 yard shot to the head in timber with the 30-378.  Still laughing about it.  Hope to knock one down next year at some distance anyway.

Thanks dude I did 2 rifles today, then broke my T10 bit on the third gun removing the scope rings from my mini 30. Can't believe ruger uses a T10 bit on the scope ring screws. Ridiculous. Talley uses a T15 bit. Much stronger and more realistic. I went and got a forged T10 bit from Milwaukee tools tonight going to try again in the morning when I'm home. I talked to leupold, looks like I have to send my Vari X3 in to have the CDS system installed. 90 bucks for the elevation install and 60 for custom dial. Hope it doesn't mess with my scope but those guys are professionals. They want to know height of the bore to scope length? Not sure why

I had to send mine in as well.  They did a perfect job, and did a full "tune up" while it was there.  Couldn't be happier, took about 2 weeks.  Maybe 2 1/2.

So when you sent yours in did it have to be dialed in perfectly at 100 yards or can you still adjust when it gets back with the dial and everything?

[dscubame]

I had to send mine in too due to a older model they needed to replace some stuff to accept the CDS.  You will tell Leupold at what distance you want zero to be;  100 or 200 is most common.  Frustrating on your wrench!  Taking my scope off was the hardest part for me mentally.  That scope leveling kit you bought is great.  I measured for eye relief for when it was time to remount.  Called the gunsmith and got the info on proper locktite too, I'll check on that.  Gunsmith also suggested a drop of locktite centered on each of the four rings pieces.

[dscubame]

Having the scope dialed in before it is sent in never came up in communication with Leupold during this process.  I am confident that is not necessary.

[wsmnut]

Having the scope dialed in before it is sent in never came up in communication with Leupold during this process.  I am confident that is not necessary.

It's not necessary.  When you get the scope back and reinstall it you'll have to re-zero anyway.  Then install your CDS dial and enjoy!

[Duckslayer89]

I had to send mine in too due to a older model they needed to replace some stuff to accept the CDS.  You will tell Leupold at what distance you want zero to be;  100 or 200 is most common.  Frustrating on your wrench!  Taking my scope off was the hardest part for me mentally.  That scope leveling kit you bought is great.  I measured for eye relief for when it was time to remount.  Called the gunsmith and got the info on proper locktite too, I'll check on that.  Gunsmith also suggested a drop of locktite centered on each of the four rings pieces.

I got the rings off and remounted with blue loctite and everything for my mini30. Luckily the new bit was strong. So I guess the last thing I need to do is measure from the very center of the barrel to the very center of my scope on my 308. Do you guys have any methods for this? I was thinking about just using a tape measure and eye balling it but I want everything to be spot on correct. I'm not sure why this information is necessary even but I'm not a ballistics guy

[7mmfan]

Will be mounting my new VX3i with CDS this weekend hopefully getting out to break it in.