how much internal moa at 1oook

[meatyrem]

Supposed I have a 300 RUM 26" with 180 Scirocco @3300fps or 200AB @3150fps Scope has 75 moa of elevation. With flat base ( no taper) will I need more to effectively get to 1k or will I need to move to a 20moa base or more?

 

[dmj]

Sure others will chime in. And I didn't run the numbers but based off my 300 win mag shooting 180 gr. ac. and my memory, you shouldn't need a 20 moa rail for a 1000 yards. Have a nice evening

 

[WildRose]

You need to run it through a ballistic calculator and print yourself off a drop sheet so you have a starting point. Your individual rifle/load combo will be different but it will get you close to start.

You will not need an angled base however to get to 1,000 yds.

Ballistics Calculator - Hornady Manufacturing, Inc

Your correction willl be somewhere around - 19-24 MOA

 

[FEENIX]

Sure others will chime in. And I didn't run the numbers but based off my 300 win mag shooting 180 gr. ac. and my memory, you shouldn't need a 20 moa rail for a 1000 yards. Have a nice evening

Check out #6 of www.longrangehunting.com/forums/f18/20-moa-base-not-87412/

 

[BMF]

Years ago I ran this set up. 185's out of my 300WM with a straight rail. Had a luepold vari-X III 6.5-20x40 on it. I could get about 900yds ( zeroed at 200yds) but that scope, I believe, only had 65 MOA of elevation. You should have enough. Although you may sacrifice being close to optically centered in your scope at that range. Good luck.
____________
Brent

 

[Wedgy]

Do you need a 20 MOA rail ? No. You have about 20 MOA drop with the 200 AB so a 10 MOA rail would keep you closer to the center of the scope. So at zero you would be plus 10 MOA from center and dialing 20 MOA you would be minus 10 MOA from center. The standard rail would put you at minus 20 MOA from center when you dial.
Hope that is clear

 

[4xforfun]

In your "supposed' setup , is the scope centered when you are zeroed at 100/200 yards, or have you already burnt up a bunch of come ups because the scope is not centered on the rifle?


Some times you need to use some of your come-ups just to get a 200 yard zero, and if you're off left or right a bunch, you will loose some more.

So...yes...and no!!

 

[FEENIX]

lightbulbTo the OP, see #4 ... one of the best if not the best advice I ever got when it comes to optics.lightbulb

Cheers! gun)gun)gun)

 

[meatyrem]

The scenario is I removed my old scope (Swarovski 3-10x42) from my 300 Rum and now the 280 Rem wears that. I have on order a vortex 4-16x44 HS-T. So I was just thinking while I have the scope off I could mount on a taper if I needed to. But if I don't all I'll have to do is switch rings out. On it now is Leupold windage bases.

 

[BMF]

You should be fine. That vortex has 75 MOA of vertical adjustment. But you'll never know for sure until you mount it. I would mount it, then bore sight it. This will get you~ close enough~ to determine how much adjustment you have left. If not, Luepold makes a 15 min. rail. I have one of these on my 300WM.____________
Brent

 

[FEENIX]

The scenario is I removed my old scope (Swarovski 3-10x42) from my 300 Rum and now the 280 Rem wears that. I have on order a vortex 4-16x44 HS-T. So I was just thinking while I have the scope off I could mount on a taper if I needed to. But if I don't all I'll have to do is switch rings out. On it now is Leupold windage bases.

From an optics SME ...

Even though the scope adjustment range may be large enough to get to 1,000 yds, you should use a 20 moa base. That's because off-axis optical aberrations that degrade resolution increase with incidence angle. You should set up your rifle so that the incidence angle is minimized for long distance shots (where resolution matters most).

Assume the base is within +/-10 moa of alignment with the rifle bore. Let's also assume your bullet drops no more than 30 moa at 1,000 yds, and you like to zero your rifle at 100 yds. With a standard base, you would need up to -40 moa of adjustment to get to 1,000 yds. That means you need a total 80 moa of adjustment.

With a 20 moa base you would need up to -20 moa to get to 1,000 yds, but up to 26 moa to get to a 100 yd zero (worse case boresight alignment in each case). That means you need a total 52 moa of adjustment. With a 20 moa base, however, the incidence angle at 1,000 yds is 20 moa less, so the image will have less blur.

 

[meatyrem]

Checked on that Leupold 15 deg base and only for a $29 option, and already having to switch rings, I might as well switch the base too, that is worth me switching to that to ensure that I will not have any problems and to ensure I will have enough moa. Which this has now turned me on to thinking about switching the base on my other Rum sendero. That wears a lupy 6.5-20x50ao 1" tall turret target knobs and no taper on the base. From what I can tell there is only about 50 moa of internal adjustment (correct me if I am wrong) with this one. I have looked and cannot find the exact one but from the closest model only has 50moa. So it appears that I will need to trade that base out in order to allow me enough room for movement out to 1k.