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View Full Version : first build - group is out of sight adj range



joedirt199
04-01-13, 12:43
this is my first build and it was from parts.

dpms slick side upper
black hole 20" SS barrel 1-8"
free floated magpul handguards
troy fixed battle rear
yhm folding gas block front sight

makes really nice groups with factory 55 gr at 25 yrd, less than .5" today but the groups are 5" low and 3" to the right. when i tried to adjust the sights to poa, my windage was going to be maxed to one side. i thought that the dpms receiver was to blame so i trued up the front and tried again. barrel is torqued down to 80 ft/lbs and sights were lined up using an L square on the top rail. i have put it together and taken apart a handful of times and the shots keep coming back to where they started. what else could i check to bring shots closer to poa? not looking to sight it in at 25 yrds, that is just the most private spot i have at the range so that i am not bothered by other shooters. will sight in further distance when i get this a little more diagnosed.

polymorpheous
04-01-13, 12:52
Magpul doesn't make a free float handguard.
What is securing it to the gas block?

Your barrel torque is a bit on the high side.
In my opinion this plays on accuracy.

The choice in gas blocks leave a lot to be desired.
My brother insisted on one and the pin that hinges the sight kept walking out.

joedirt199
04-01-13, 12:55
there is a dcm white oak tube under the handguards so they are free floated. works really well. i got the gas block when all others were out of stock. pretty much the wrong time to build an AR, hence the random parts used. gas block is a clamp down style and i checked to make sure the gas block hole is on the top of the barrel and not canted, which it is straight up.

when i torqued to 75 ft/lbs the first few times there was no shift in impact. they still hit low and to the right.

JR TACTICAL
04-01-13, 13:09
Wait, so you have a FF tube on your rifle, but you have a set of magpul handguards on it as well?

Is this what you have under the Magpul handguards?

http://www.whiteoakarmament.com/xcart/product.php?productid=17658&cat=286&page=1

eodinert
04-01-13, 13:44
Who makes your gas block?

joedirt199
04-01-13, 13:46
yes that is what i have. found a thread on ar15 where a guy used sandpaper over the free float tube to get the handguards to fit. was pretty easy and they fit nice. adds some extra wieght to the front with the steel float tube but not terribly bad.

gas block is a yankee hill folding front sight

Iraqgunz
04-01-13, 14:32
You have a Joe Bubba build slapped together from crap components and you wonder what's wrong? I know its April Fools, but c'mon.