20 or 40 MOA

trueblue

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Looking for feedback on which rail to use. I am shooting 300gr SMK @ 2800fps, but am looking into stepping up to 3200 fps.Either one of these zeroed @ 100 has from 19 to 26 MOA for dial up at 1000yds.Based on using a Nightforce 5.5x22 scope, do you go with the 40MOA rail and dial the scope all the way down, or go with the 20MOA rail and have it more optically centered at the 1000yd distance when shooting ?
 
Looking for feedback on which rail to use. I am shooting 300gr SMK @ 2800fps, but am looking into stepping up to 3200 fps.Either one of these zeroed @ 100 has from 19 to 26 MOA for dial up at 1000yds.Based on using a Nightforce 5.5x22 scope, do you go with the 40MOA rail and dial the scope all the way down, or go with the 20MOA rail and have it more optically centered at the 1000yd distance when shooting ?


.338 Lapua???

With the NXS, I'd think 20MOA would be plenty....


Scott
 
It depends on what yardage you want your zero.
You can't get a 100 yard zero with a 40 moa base, it will be somewhere at 750 yards. Been there.
With a 25 to 27 minute base and an 8x32 NF you will be roughly 8-10 moa off the bottom, have a 100 yd zero, and have about 55 moa left. Enough to get you to roughly 1800 yds.
With the 40 moa base you'll be zero around 750 yds with about 65 moa available. Should get you enough operating space for 2000.

There are a few other options with rings and optics...

It all depends on what you want..
 
Looking for feedback on which rail to use. I am shooting 300gr SMK @ 2800fps, but am looking into stepping up to 3200 fps.Either one of these zeroed @ 100 has from 19 to 26 MOA for dial up at 1000yds.Based on using a Nightforce 5.5x22 scope, do you go with the 40MOA rail and dial the scope all the way down, or go with the 20MOA rail and have it more optically centered at the 1000yd distance when shooting ?

If you are shooting the 300gr SMK only to 1000yds at 3200fps you dont need to add any MOA. The question I have is if you are shooting a 300gr SMK at 2800fps how are you "stepping" it up 400fps to 3200fps ???????
I am shooting the 300gr SMK at 3050fps and was thinking of stepping it up to 3450fps, I only made it to 3075fps before my primers started to crater.
At 3050fps I have 40 MOA added and have shot it past 2000yds. I also have a 70 MOA base but have not tried it out yet.
UB
 
Uncle B,
Been looking at the 338/408 Chey-Tac which will get me 400fps more velocity and a third less wind drift with 300gr SMK.Right now shooting the 338 EDGE at 2800 fps. The 338/408 improved (AM) is what I am seriuosly looking at. Don't plan on shooting past 1500yds for awhile,after all there is a great learning curve at these distances, so I don't think I need a 40MOA rail.Probably go with a 20 MOA rail, but just wanted some responses from those that are in the know.

JOEL,
Thanks for the details on your set up. Until I learn to shoot at these distances, from your post it seems the 20MOA rail would be more appropriate at this time.
 
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Joel,
Quick question about your set up. What ring height are you using with the 8x32 scope, and is that what is determining your zero @ 100 with a 25 to 27 MOA base. Will a 5.5x22 50mm objective with 1" rings have a 100 yard zero with a 30MOA base ? Also, I have not seen a 25 MOA base advertised. They are usually listed as 20/30/or 40 MOA. Where are you getting a 25MOA picatinny rail ?
 
I had the 1" rings with a 27 moa base. In the process of switching to a different ring/base. ;)

I had a 40 moa base in the shop, and put it on. That gave me roughly a 750 yard zero with my combination. All my rifles have a 100 yard zero, so this rifle was no different than the rest. I calculated where I needed to be to get my 100 yard zero, and still stay on the bottom of the scope. Then I made a 27 moa base. That gave me my 100 yard zero and still afforded me roughly 55 moa of useable space with the 8x32 NXS.

The 5.5x22 NXS has 100 moa, so all things being equal, that 27 moa base will give you your 100 yard zero and still afford you roughly 90 moa of useable space. The only difference is that you are giving up 10X, which is significant when you get way out there.

You will be close to a 100 yard zero with a 30 moa base.

Remember, you always want to operate in the optical center of the scope.

If I confused you, give me a call you have my number...
 
Uncle B,
Been looking at the 338/408 Chey-Tac which will get me 400fps more velocity and a third less wind drift with 300gr SMK.Right now shooting the 338 EDGE at 2800 fps. The 338/408 improved (AM) is what I am seriuosly looking at. Don't plan on shooting past 1500yds for awhile,after all there is a great learning curve at these distances, so I don't think I need a 40MOA rail.Probably go with a 20 MOA rail, but just wanted some responses from those that are in the know.

JOEL,
Thanks for the details on your set up. Until I learn to shoot at these distances, from your post it seems the 20MOA rail would be more appropriate at this time.

trueblue,
Now that I know more about what your plans are let me try and steer you in a different direction.
I agree with you there is a "great learning curve" "past 1500yds" but why do it with a 338AM. If you were to choose a capable cartridge such as a 6.5-284 to do your 1500yard learning curve and then switch to the 338AM you will save yourself literally thousands of dollars and learn how to read conditions better.
it is at least worth considering.
UB
 
Uncle B,
I have a capable .338 ( EDGE ) at present that is more gun than I probably would ever need. The reason that I am looking at the 338/408 Chey-Tac is that it gives me a cushion of 20-30% in reading the wind correctly. Being strictly a bow hunter for 20+ years, I do not want to take an irresponsible shot at an animal, so when I started shooting a rifle this winter I want to do everything in my power to make sure I am taking the best shot that I can. There is also something to be said for learning with the rifle you plan to hunt with. Thanks for your comment thou.
 
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