Rifle Scopes Do I need an additional 20 MOA scope mount with a 20 MOA scope rail?

[sirricky85]

Hey guys, first off I want to say I'm new to long range shooting and that I appreciate the vast knowledge on Sniper's Hide. I've been reading threads in the background for a week or so now.

Set up: Masterpiece Arms .308 Bolt Action, Vortex Viper PST Gen II 5-25x50, and Federal Sierra MatchKing 175g

Background: The reason why I'm asking this question is that the vendor I'm getting the MPA 308BA from has a concern about the scope mount I ordered (MPA BA Mount - 30mm, 1.125", 0 MOA). He was saying that I would only be able to reach out to 600 yards with this setup and that he wanted me to be happy with my purchase, so he's recommending me to go with a 20 MOA scope mount to reach out to 1000+ yards. For you guys that don't know the MPA 308BA comes with a 20 MOA scope rail. Would I need the additional 20 MOA from the scope mount to reach out to 1000+ yards? With the knowledge, I gained from here, other sites, and similar data... it seems like I would not. Did I fail to pick up some information into my long range shooting journey? Are these the only cons for going with a 40 MOA set up: may not be able to zero at 100 yards, have windage adjustment issue at the extreme end, and reduce in picture quality?

Thanks for your input Sniper's Hide.

 

[brianf]

A average 308 shooting federal 175 will take 35-38 Moa of elevation
Your scope has approx 70 total (35 up and down from center)
A 20 Moa rail adds 20 to the 35
Giving you approx 55 Moa of elevation (say 50 because you use some for zero), more than enough
But the farther you get from the optical center the more the image suffers
That being said, your fine in my book

First 1000 yard shot I took was with a 308 shooting 175's using a lup mk 4
Had 70 Moa of adjustment as well
Had a 20 Moa rail, never bottomed out the scope
First round hit too, although I wasn't callin the wind yet

 

[Ryridesmotox]

I use a howa 308 with a 20 inch barrel. I have a Burris 25moa rail and an athlon argos BTR. 1k is easy peasy. I use a handload with 178 hornady going +/-2700fps.

You won't need 40moa of cant to hit 1k. Maybe he forgot 20moa was built into the rail already.

 

[Steel head]

20 will be fine.


With 40 total you may not be able to zero at 100 yards.

 

[Huskydriver]

20 is more than adequate for a 308 at 1k.

 

[sirricky85]

Awesome. Thanks for your reply guys.
He's actually aware of the 20 MOA on the scope rail already... I feel like he's just trying to push me on buying from his inventory. Kinda shady IMO.