trueing the face of your AR upper receiver.

[oli700]

real good shooting considering an 1/8" is smaller diameter than a 5.56 projo

 

[Heywood]

Dood.. a 1/8 MOA garage built AR that's as accurate as a 2 MOA hunting rifle? Wow.
This is exactly why I use a shotgun on those 25yd beer cans! blammo!

I didn't remember writing 1/8 moa...bro.
Plus many people are still of the impression a home built semi auto can not be as accurate as even a semi custom gunsmithed hunting rifle. Dooood.

 

[Certaindeaf]

I didn't remember writing 1/8 moa...bro.
Plus many people are still of the impression a home built semi auto can not be as accurate as even a semi custom gunsmithed hunting rifle. Dooood.

Yea, I wouldn't worry about it.

 

[DingDongMF]

I have done several and not one upper as of yet has been square. Should I have sent them all back?
This discussion comes up occasionally on another site and opinions are split between people who have never done it that say it is not needed and people who use it and say it's worth it.
Yes you can zero a scope or red dot just fine, but if you have fixed irons and your windage is to one side more than you care then this could be your ticket.
I don't have one upper with crazy windage problems.
If I buy a complete upper that zero's fine I'm not going to pull it apart to square the front but if I am building one then for sure I will true it before assembly. Why not? It is so easy.
On another note the tool more than pays for itself if you have a fixed FSB and you can't get the barrel nut to line up.

 

[Heywood]

real good shooting considering an 1/8" is smaller diameter than a 5.56 projo

Who said 1/8 "? And who said 5.56?
As an aside, 1/8 moa does not always equal 1/8"
Also, properly measuring a group will often result in that group equaling less than the diameter of the projectile.
I.E. Measure group from center to center, or measure outer diameter of the group. then subtract bullet diameter. Which gives you group size. When you start shooting groups that touch, that is the only way to measure improvement.
This group was the first group shot with my rifle and I used factory ammo. I use bags only, no sled or vice or any other aid. I have since gotten better groups from hand loads and shooting at longer ranges. Not every group is that good but I can do close to it or better at least once when shooting at 100 yds.

 

[Velzey]

How are we checking uppers to see if they are square?

 

[mjbskwim]

With the rail on top?

 

[Heywood]

What kind of upper is it?

The most recent is a mega side charging billet upper. Which turned out, did not need to be trued, I also had to heat fit the barrel extension to the receiver. They are good. I also know that the seekins precision uppers I have seen did not need it either. I have second hand knowledge of a few other makers but do not know first hand so I won't say. But I will say most are not squared to "my" expectations. Whatever that's worth.

 

[Certaindeaf]

Who said 1/8 "?.

I said 1/8 MOA because you said "The result is a better than 1/4min. AR15 built in my garage." in post #19.
Last I checked "better than 1/4min" means smaller than 1/4min and guess what.. 1/8min is smaller or "better" than 1/4.
sheesh

 

[ConcreteJungle]

i "trued" my barrel and upper when i was building it years ago. so no problems here.

 

[oli700]

Who said 1/8 "? And who said 5.56?
As an aside, 1/8 moa does not always equal 1/8"
Also, properly measuring a group will often result in that group equaling less than the diameter of the projectile.
I.E. Measure group from center to center, or measure outer diameter of the group. then subtract bullet diameter. Which gives you group size. When you start shooting groups that touch, that is the only way to measure improvement. View attachment 253737
This group was the first group shot with my rifle and I used factory ammo. I use bags only, no sled or vice or any other aid. I have since gotten better groups from hand loads and shooting at longer ranges. Not every group is that good but I can do close to it or better at least once when shooting at 100 yds.

no disrespect but groups start at five rounds in my book.....good shooting none the less.....

 

[Heywood]

no disrespect but groups start at five rounds in my book.....good shooting none the less.....

I hear you, in my book, groups only count for reals with a fighting rifle, When you do them away from a bench...
For this reason, three round groups to confirm zero is more than enough. I'm not made of money.

 

[SheepDog223]

No way guys. Groups only count after 3 days of total sleep deprivation, overland mountain ops in sub 15° weather with two instructors per trainee who are looking for you to give away your position.

Stop measuring wee wee's guys. Groups count. Most people shoot three. Some only count cold bore hits, depending on what your mission is a full auto spray with everything inside of center mass is a stellar group.

If your making hits, that's all that counts. Everything else is just pride.

 

[oli700]

I hear you, in my book, groups only count for reals with a fighting rifle, When you do them away from a bench...
For this reason, three round groups to confirm zero is more than enough. I'm not made of money.

you and I are alike , but I only test reloads in threes ....because as you say money.

Wind is my biggest enemy

 

[oli700]

If your making hits, that's all that counts. Everything else is just pride.

that's great for you but for others just making hits is too ........easy .
I demand quite better from myself, others can do what they want
I am in competition with only myself and take great pride in topping myself and getting better so I'm not measuring nothing with anyone
No one here has a problem with anyone else in this conversation but thanks for the pep talk

 

[Heywood]

you and I are alike , but I only test reloads in threes ....because as you say money.

Wind is my biggest enemy

Wind is my biggest problem as well.

 

[Cameron72]

I bought a Caldwell tool ($35) when I started building uppers. I check the true of all my upper receivers before assembly. Most are fine. Another benefit is aligning the barrel nut for the gas tube.

 

[oli700]

I bought a Caldwell tool ($35) when I started building uppers. I check the true of all my upper receivers before assembly. Most are fine. Another benefit is aligning the barrel nut for the gas tube.

the barrel nut is the reason I've seen it done

 

[Member 5605]

How are we checking uppers to see if they are square?

Against a politician.