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73Dustr
12-25-2008, 06:46 PM
Well, I got a new DPMS flat top. I am going to set it up as a predator gun with a 4-12 or 4-16 scope. What do you guys recommend for rail extensions?

Russ Jerome
12-25-2008, 10:51 PM
Your DPMS may not need extentions, most of the newer
Varmint grade guns have a slightly longer rail. If you
can, keep it as low as possible, there are lots of good
scopes with as little as 3" eye relief, relief is actualy
setup for high power rifles and not knocking your eye
socket out :)

My plan is to settle on the scope I am buying (this week)
and then trial fit without extentions. For all out target
accuracy you want it low as possible with your eye happy
with the scope mount. Adding a big LaRue extention will
also raise your scope away from the barrel, great for human
size targets but we want to hit dime size holes from 20yrds
all the way to 300yrds.

The AR15.com guys are cool but there idea of accuracy is
a halo with no zoom mounted 3+ inchs off the barrel, not
the cool varmint setup. Graybeard.com outdoors is pretty
good.
http://www.go2gbo.com/forums/index.php/topic,159743.0.html
As you can tell I am looking into the subject of target
accuracy with high mounts myself, he makes a good
point on the POI and 220yrd zero.

Russ Jerome
12-25-2008, 11:06 PM
Undoubtably someone will bring up "longest point blank"
range as a reason to mount the scope higher to the bores
axis and the bell of the scope. These arguments dont hold
true on small center fires with such high ballistic efficency.

The 3000+fps 223 is like a fast pitch MLB player and the
308 (that I love!) is more like a bar league softball guy
lobbing one to the plate, they can take advantage of that
smooth arc where the 5.56 gets there yesterday and dies
quickly later (55gr vs 150gr). The flatter the bullet (223
is up in the top 5 I believe still today) the closer the scope
to the barrel to have the longest POI accross the field. We
dont want 3.5" of holdover for Bobcat up close.

73Dustr
12-26-2008, 12:12 AM
Yeah, I completely agree, you want the scope as low as possible. Goes hand-in-hand with the concept of the Leupold VX-7. I have the scopes on all my rifles as low as possible. Just like you, I am setting this thing up for long range accuracy, not tactical use (like many of the guys on AR15).

I was also thinking about test fitting a scope without the extensions to see if it would work. I am thinking about a Burris Fullfield II in a 4.5-14. I also want to toss a vented handguard on it. Eventually, I'd like to throw on a Magpul PRS stock. Right now, my main priority is getting a scope on so I can get out shooting.

Thanks for the link.

Russ Jerome
12-26-2008, 04:05 PM
Right now, my main priority is getting a scope on so I can get out shooting.




Me too! Im gonna buy a cheap azz 50mm thats the same
external dimensions as the one I want just to get a feel.

The only drawback to the AR chassis is the dam spring
in the stock, your gonna have to have it elevated a bit
regardless.

I've always liked 50mm scopes for low light, here is a
stupid Idea I have.... Since it has to be mounted high
why not buy a HUGE objective like a 55,60 or hell even
a 70mm! I mean if the scope has to be high why not
buy the biggest objective you can since the scope stands
no chance of touching the handgard??? Im gonna ask a
high end rifle guy, he will probably laugh and say I should
have kept my 700 action 243 and had a better long range
gun :)

73Dustr
12-27-2008, 02:07 PM
Since it has to be mounted high
why not buy a HUGE objective like a 55,60 or hell even
a 70mm! I mean if the scope has to be high why not
buy the biggest objective you can since the scope stands
no chance of touching the handgard??? Im gonna ask a
high end rifle guy, he will probably laugh and say I should
have kept my 700 action 243 and had a better long range
gun :)

Not a bad idea. I ended up mounting a scope on it last night. I was going to get the Fullfield, but I had a brand new 4-12x44 scope that I was going to put on my old varmint rifle. I figured, I'll upgrade to the Fullfield in spring. I had very good results with Warne Maxima Series rings at a medium height. The bell is probably 1/8" above the handguard and there is enough clearance for the charging handle. I did try mounting with some low rings I had laying around, but they were just a hair too short. Plus it would've been almost impossible to operate the charging handle. I also had enough room on the receiver so I didn't have to get any type of rail extensions. I would definitely look into the Warne rings if you haven't gotten any yet. They are very solid. The best part was that they only cost $29.99 at Cabelas.

Russ Jerome
12-27-2008, 04:32 PM
Oddly enough Im going to Cabelas and Gander in minutes!
I like the Burris Tactical rings, will look at those too.

Get some pics up!

73Dustr
12-27-2008, 08:08 PM
Oddly enough Im going to Cabelas and Gander in minutes!
I like the Burris Tactical rings, will look at those too.

Get some pics up!

I like the Burris Tactical rings as well. The things are little tanks. Unfortunately, I did not see any at Cabelas when I was there. I'll try to get some pics up after I'm done with my batch of handloads.

Reverend Cooper
12-27-2008, 09:40 PM
2-7x35 vortex scope for the win just got it today

Russ Jerome
01-01-2009, 10:51 PM
Matt Burkett came up with this great 45* mount, keep
your scope up and center and hang your RedDot at 1:30
position on same rail:
http://www.mattburkett.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=21&category_id=3&option=com_virtuemart&Itemid=28

There is a great picture of it in action in this months G&A
Book of AR but I cant find an online pic. All you do is turn
your AR 45* and there is your quick Halo sight for running
rabbits....or other fleeing game.