What degree picatinny a 20 or 10 degree?

G

gt40

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I have been looking at this EGW picatinny rail. What do you think?

http://egw-guns.com/store/index.php?main_page=product_info&cPath=39_128&products_id=224

The rifle I will put it on is a 6mm BR. Norma using 105 gr. Berger VLDs. If I only shoot out only 600 yards should I get the 20 degree or should I get a 10 degree or will a flat rail be ok? How will it affect my hold at 100 yards for both the 20 & 10 degree rail? Will I be able to adjust the reticule down to be sighted in at 100 yards with a scope that has 80" of adjustment? :confused:

"Aim small miss small", :D

gt40
 
The answer is...

Neither. 10 degrees = 600 minutes of angle, or roughly 603" difference @ 100 yards. 20 Degrees = 1200 minutes of angle, or 1206" difference in point of impact at 100 yards.

Now a 10 minute rail (MOA) shifts point of impact about 10.5" @ 100 yards, while a 20 MOA rail shifts point of impact by about 21" @ 100 yards.

I'm guessing the comeup from 100 to 600 yards for your cartridge is about 15 to 17 MOA. Based on past experience, and given your two choices, I'd go with the 20 MOA rail.
 
gt40

If you are really going to limit your shots to 600 yd don't bother with an angled base. A 600 yd trajectory with a 6BR and a 105 grain-ish bullet will require about 12 moa above a 100 yd zero. With the 80 total moa adjustment (total, 40 moa each way) that your scope claims you will you be using less than 1/3 of the available range and be just fine. If you later decide to shoot out to 1K yd. put a 20 moa base on your rifle. With that setup you're still ok at 100 and have a mechanical zero roughly half-way between 600 and 1K. so no problems with available windage adjustment or funky scope behavior.

Greg
 
I have a .223 I wanted some extra range with and added a 20 MOA. rail. If your gonna spend the money go ahead and get the 20moa. I still have a 100yd zero and probably more range than I may ever use. ( this is not an F class rifle I'm talking about just an experimental for fun rifle)
 
I just ordered the medium Burris Tactical Extreme 30mm rings from SWFA. The scope that I have on it now has a 30mm tube with a 50mm objective lens. It is atop a EGW 20 MOA with 1" high rings. With this set up the bottom of the objective is 3/4" above the barrel. If I used the 1/4" rings the scope would almost touch the barrel and I do not think I could fit lens cover on it. With the 1/2" rings this leaves me 1/4" above the barrel. I do need to mention that I have a heavy barrel with a straight taper to the muzzle.

"Aim small miss small", :D

gt40
 
GT40....

Funny thing is I did the same math the other night for a 6BR for 300M to 600 yds ONLY. What I'm thinking is to get the scope into it's optical center I'm thinking of just mounting it without any rail on it and using the Burris rings and a -10 MOA shim and then just dialing up 20 MOA on the scope. So my math is ... 0 base moa + 20 MOA on the scope less 10 MOA in the -10 shim = 10 MOA on the rifle itself, which should be centered in the scope and on target at 600 yds give or take a click or two. Yes, as I move in to 300M the scope will be 7-8 MOA below it's optical center, but still close enough and 10.8 MOA should be all you need from 100 to 600 yds with a 6BR. I too have a 20 MOA rail on order and if I use it, I'm thinking of putting it on backwards so it is a -20 moa rail and then use Burris shims (the +5 moa) to get some back. Again, my math here is -20 moa via rail plus 5 moa in a +5 moa shim would give -15 moa on the rifle itself, then dial up as needed so 300M would be around 17.3 moa on my scope(200 yd zero, which should be +15 moa on the scope) or 2.3 moa up from 200 yds and 600 yds would be 25.8 moa on my scope or 10.8 moa up from my 200 yd zero. This would allow me to work from 17.3 to 25.8 on my scope and 20 moa should be centered, optically. My scope has 40 MOA in it in total.
 
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I have a Nightforce Benchrest scope with 40 MOA total elevation adjustment. A 20 MOA base will put your scope right at the edge at 100 yards. I use a 15 MOA base and it puts me right on at 600.
 
The new scope I am getting is supposed to have 65 MOA of adjustment. Here is a computer generated drop chart for my 6mm Norma BR. shooting Berger 105 gr. VLDs at 2950 fps.

Which distance should I sight in at so the cross hair would be the closest to center of the scope with my 20 MOA rail? ( I may be getting CORNfused ).

Thanks,
gt40


Here is a program generated drop chart, not exact as you'd have to tune it to your conditions but will give you an idea
6mm BR/105 berger/2950 fps BC .532
zeroed at 100
100 0
200 -3
300 -11
400 -25
500 -46
600 -75

zeroed at 200
100 +1.5
200 0
300 -6.7
400 -19.3
500 -38.7
600 -65

zeroed at 300
100 +3.7
200 +4.4
300 0
400 -10.4
500 -27.5
600 -52.5

Your load retains 1000 ft/lbs of energy to 525 yards, at 500 your hold over or dialing would be
100 yd zero 8 MOA
200 yd zero 7 MOA
300 yd zero 5 MOA
with a 300 yd zero hold under/over with a moa reticle would be
100 4 moa
200 2 moa
300 n/a
400 2.5 moa
 
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Scope MOA

Patience with the obvious answer easy question, please. Not knowing the true or advertised MOA range of a 12 yo scope, is this determination as easy as seeing how many clicks up, down, or both combined ?

The scope under the dust cap is Labeled

1CLICKO 1/4 100yds

Thanks :)
 
Flouncer, the easy way, set the rifle up at the range on a good solid rest and aim at a target, then click it all the way down to the bottom (make sure the hairs move as you click it by watching in the scope) and then click it up and make sure the hairs move as you do it, If you click and the hairs stop moving, you are out of adjustments internally. Yes, some scopes you can click and the hairs will not move once you get to the end of the "clicks". All you have to do it count the clicks that moved your cross hairs and divide by two to get you the the center of the scopes adjustments.

Keith
 
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Captain Obvious

So, with my scope referenced above, if I get 40 up and 40 down, is that roughly 40 x 1/4-inch = 10 inches up/down at 100 yds ?

If the Sierra Table shows the 140g SMK @ 2800fps requires 33 inches over at 100 yds to be 0-inch at 1,000 yds, then I would be SOL without either holding high, or getting a base shim ??? - Thanks.

This is not benchrest precision or accuracy I realize. Reality is a brutal teacher to students with a Lee Loader budget and 1,000 yd X-ring dreams. My eventual goal is to hit a door-sized sized target at a thou with a 98-yo military action and handoads from the garage. I am very aware that goal is far away literally and figuratively. :)
 
You normally want to use an inclined base of less than half of your total vertical adjustment. My scope has 40 MOA and I use a 15 MOA base, any more and I wouldn't be able to zero at 100 yards.
 
20 Worked for me

I am by no means an expert but here is what I did. I used the EGW 20 moa base on my blueprinted 700 action in 6.5X284. The scope is a Leuopold 8.5 X25 with a 30 mm tube. I set it up for F Class shooting. Much to my suprise I could shoot from 100 to 1000 yards with this setup. I used Burris Signature rings so I could mess with the scope but was able to leave the rings alone. I have messed with several other setups and not been so lucky. I would recommend giving the 20 moa base a shot - you may someday want to shoot farther out. The quality of the EGW base was as good as any I have ever seen - you won't be unhappy with their base. Good luck!
 
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