Do I need a rail with built in MOA?

[wethington123]

It’s not just low-end optics. Short, compact, high-magnification scope designs tend to struggle with this more than others, IME. The Bushnell DMRII 3.5-21x was one of the worst I’ve seen.

Good to know! Haven't heard that, thanks.

 

[JDMBEND]

What is the downside to a 20 moa rail?

 

[Fred@Exterra]

Personally, I prefer rails that have mil elevation, instead of MOA. But that’s just me.

I definitely use a Mil rail with my FFP fixed power scope. Bomb proof combo.


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[Dave Thomas]

I didn't know that was an option, that shows how much I've looked into this. My scope is in mil, so going this route would only make sense.

It's a joke just like a metric crescent wrench.

 

[fuzzymarindave]

I'm in the middle of a rifle build, Rem 700 in 280AI. I plan to shoot 180 ELDm @2800, hopefully. I currently have a Nightforce 4-14x50 that I plan on using. I now need a mounting system, but I'm unsure what to go with.
My plan is to shoot out to 1000.

My experiences: I took two rifles to a long range course and both had 0 MOA rings mounted directly to the receiver. Both scopes allowed me to get to 1000 yards easy. The Leupold VX-6HD ZL3 almost got to 1-mile with dialing but came up a little short and I had to use the hash marks on reticle to hold over. The Leupold VX-6HD ZL2 did not have enough travel to get much past 1000 yards.

 

[coyotekilla]

So I plugged in a 280ai into the hornady app... 180 eldx I think @ 2600 fps. Maybe your barrel will be shorter, maybe the barrel will be slow. Basic calculations say 30 moa.

Id go with a 20 moa rail cause there really isn't a downside. Plus if you want to stretch it farther your good to go.

 

[Jordan Smith]

Good to know! Haven't heard that, thanks.

The DMRII Pro is a bit better with its improved glass coatings, but it still struggles when the erector gets much more than 5-10 mrad from mechanical center. A the extremes of the erector travel, the DMRII (non-Pro) is like looking through a fish bowl - darn near unusable if there is any mirage at all. The Pro is decent and usable, but not great.

FYI, I've owned and used 5-6 of each with the same results, so it wasn't just a single bad sample.

"Cheap" scopes aside, I've seen this behaviour in other mid-to-high-grade compact, high-mag scope designs, as well, but the DMRII is one of the worst I've used.

 

[Brandon_SPC]

I would try it without it first. My 6mm ARC doesn't have one and I am able to reach out to about 800 yards without one and that's shooting 108 eldms at 2550 fps around sea level with my Leupold Mark 4HD 2.5-10.