Probably the newbiest AR build questions you'll read all day

[GSoD]

So I'm slowly working my way through my first AR build and have some questions.

a) LPK - do they all pretty much do the same thing. For example, is getting the RRA one from Questar satisfactory or should I be putting alot of work/research into this.

I'm assuming that if I'm not building a precision target rifle I really have no use for things like a 2 stage match trigger. Is this correct?

BTW: if anyone has an extra LPK to sell I'm buying one anyways and could take it off your hands.

b) Uppers - my plan is to buy a complete upper in a couple of months. The question I have is, how complete are they? For example: do I need to worry about things like bolt, carrier, charge handle etc when buying a complete upper? Or is a complete upper ready to fire after mating with a complete lower?

Any helpful advice appreciated.

Advance apologies if too newb.

 

[Grizzlypeg]

Can I add another question to your list? If a guy buys a lower from once company, and an upper from another source, how likely are they to be 100% compatible? Does a gunsmith need to be involved at times to fit them together, or do they alway mate up?

 

[X-man]

RRA makes fine parts and just about every company's lower parts kit include the same parts. A little known fact is that many of the current "big" AR manufacturer's all purchase their small parts from a small group of outside suppliers such as CMT.

As for the definition of "complete" uppers, some makers sell them complete with BCG/bolt, others don't. Ask before you buy, although, you'll probably be better off keeping an eye on the EE and picking up a low mileage used upper.

Unless you're dealing with a Colt "large hole upper" or lower, essentially all current AR manufactures should be within specs and thus able to correctly mate with another manufacturer's lower/upper. There are some exceptions, however, so that is why it is better to pay a little extra for an upper tier manufacturer rather than the lowest/cheapest you can find.

The one thing you will find though is that often the finish on different uppers/lowers, even from the same manufacturer will often not match! Can be annoying to some, to others...m'eh. Doesn't affect shootability in any way. No gunsmithing required and if it is, you have a defective upper or lower that is out of spec and should be replaced at no charge.

 

[Hungry]

RRA's stuff is great. Mark and his crew over at Questar in Barrie are fantastic to deal with. You will not go wrong buying from them.

LPK's ?? I've been successful (about 10 builds now) with all of them from DPMS, Bushmaster, RRA, etc. Everything worked out well.

You are wise to ask questions here!! We are all helpful!

 

[GSoD]

Excellent, thanks guys.

Two more:

1) Barrel length - Like I said, I'm not looking to build a precision rig. I already have a bolt gun for that. I'm looking for a CQB styled paper puncher.

Looking through the AR pictures thread I found one that I really liked the look of. It was a 10.5".

Now my question is: is there any disadvantage to going short that I'm not seeing? Or is it all a matter of taste and preference.

2) I'm looking to go with iron sights. Does this affect what type of upper I get? Or do I get an upper and then worry about the sights after?I change my mind and decide to go with an optical setup afterwards do I have to get a new/different upper or can the upper be modified to accept optics?

 

[lmar]

Excellent, thanks guys.

Two more:

1) Barrel length - Like I said, I'm not looking to build a precision rig. I already have a bolt gun for that. I'm looking for a CQB styled paper puncher.

Looking through the AR pictures thread I found one that I really liked the look of. It was a 10.5".

Now my question is: is there any disadvantage to going short that I'm not seeing? Or is it all a matter of taste and preference.

2) I'm looking to go with iron sights. Does this affect what type of upper I get? Or do I get an upper and then worry about the sights after?I change my mind and decide to go with an optical setup afterwards do I have to get a new/different upper or can the upper be modified to accept optics?

Shorter barrels are "LOUD". I purchased a longer 14.5" version for this very reason. Noveske (sp) sound modulators are used to cut down on the bark generated by the still burning powder as it exits the shorter tubes.
Also, the longer sight radius of 14.5" allows me to reach out to 200 yards with it. While I liked the look of the 10.5" tube I figured another 4" made a significant difference in the sound signature.
Haven't had any personal experience but the shorter barrels have a tendency to foul up quicker and have timing issues based on my research.
Can anyone with real world experience confirm or add to this point?

Your 3 main options are to

1. Get a flat top with no front base which means you have to purchase extra BUIS for the front and rear or use optics only.
2. Get a flat top with the front sight base and use the detachable carry handle with built in A3 sights. Should you want optics you'll remove the carry handle and put optics with high enough mounts to co-witness with front sight.
3. Get a tactical handguard that contains a short rail and A3 rear sights. This allows you to use sights and then add optica aiming device to co-witness with built in sights.
4. Repeat 3 without front sight base and have flip up BUIS on the front.

Have I missed any other obvious options?

L