Building a PSA AR based rifle

[hatt]

Mid length is going to be easier on the components as well. Port pressure is much lower. It also corrects the problems that led to the carbine gas guns needing extractor o-rings, H buffers and so on. Only way I'd buy a 16 inch carbine gas gun these days is if it said Colt or was a smoking deal.

That rifle gas 16 inch dissipator in the above pic would be a no go.

 

[HankC]

"Only way I'd buy a 16 inch carbine gas gun these days is if it said Colt"
Colt does not offer a mid-length, don't they!

Military M16s have carbine length gas system and fired many many rounds. If solders can use carbine gas system in battle field, civilian can shoot them in shooting range. My first AR was carbine length and heard all these carbine length gas system crap, figure I should either get a mid length or rifle gas system to see how much difference. Bought my 2nd AR in 20" rifle, honestly cannot tell significant difference! Port pressure is higher for carbine, but the gas hole is also smaller. Unless the hand-guard is free float, may want to hold the rifle near barrel nut anyway. I think the biggest advantage of mid-length is 2" longer sight radius, mid-length is nice but I would not pay extra just for mid-length.

 

[Jackal]

http://www.gunbroker.com/Auction/ViewItem.aspx?Item=368277784

Run away. You really have no idea if its a PSA build or not. Also, BCG has 1 sentence devoted to it with no details, likely a $80 el cheapo BCG. I would run away from any upper (or seller) that has 12 lines of text about the cheapo quad rail and barely a sentence about the most important part, the BCG.

Run away and buy from a reputable seller with known components.

 

[ugaarguy]

Military M16s have carbine length gas system and fired many many rounds. If solders can use carbine gas system in battle field, civilian can shoot them in shooting range.

I assume you mean the M4 carbine, and not the M16 rifle. While it's true that the M4 carbine uses a carbine length gas system, it also has a 14.5" bbl. The further the bbl extends beyond the gas port the longer the dwell time. Longer dwell time increases the volume of gas in the system. The mid length gas system on a 16" bbl gets the dwell time much closer to that of a 14.5" bbl with carbine gas, or a 20" bbl with rifle gas.

That aside, the commercial market has been using 16" bbls with carbine length gas systems for decades. Rifle build quality is going to be far more important that gas system length for reliability.

 

[HankC]

Yep dwell time. That explains a lot about an 18" AR with mid-length gas system and 24" AR with rifle gas system!

 

[cowtownup]

Okay, thinking about pulling the trigger on this upper... Is this a good deal??

http://palmettostatearmory.com/inde...ipped-upper-with-bcg-and-charging-handle.html

 

[Jackal]

Its a great deal. The BCG isnt top of the line, but it will be on par with anything coming from any of the other major manufacturers (Stag, RRA, Windham, etc).

Here's a great budget build for $1,038.96 including excellent optics and shipping to WA.

http://palmettostatearmory.com/inde...ipped-upper-with-bcg-and-charging-handle.html
http://palmettostatearmory.com/index.php/psa-blemished-safe-fire-lower.html
http://palmettostatearmory.com/index.php/psa-acs-l-lower-build-kit-black.html
http://palmettostatearmory.com/inde...luminum-flip-up-front-and-rear-sight-set.html

 

[boricua9mm]

I'm not impressed with PSA's abilities in building uppers.

Mine came with finger-tight freefloat rail attachment screws and the rail was improperly installed. Thankfully, I checked the screws for proper torque. I also found that the low profile gas block set screws were only finger-tight and that the barrel was not dimpled prior to installation. There was also no threadlocker of any sort on the gas block screws. Considering the ~30,000 PSI of port pressure, I expected a little more attention to detail on the gas block installation.

It'll be harder for PSA to mess up a basic upper, but I would expect an upper that still needs a good "once over" before running it through its paces. A half-done parts kit upper, if you will. In my case, second-guessing PSA turned up some very poor assembly methods and my corrections were required to make it right.

Since this is your first AR and you might not have all the tools or know-how to correct a poor assembly job, I would suggest buying a complete BCM, DD or Spikes upper and a good BCG from either of them.

If an M4 configuration is the goal, then a Walmart Colt 6920 really is the best answer in the long run.

 

[cowtownup]

Thanks for the help... I ordered that upper.. Looking forward to learning more about these rifles...

 

[cowtownup]

Which rear MBUS sight will I need to work with that upper?

 

[Jackal]

Which rear MBUS sight will I need to work with that upper?

Most any rear sight will work. Fixed or folding, whichever you like.

 

[cowtownup]

Well here it is... Its gonna have to stay like this for a while until I can get some funds saved up, however I was able to get dies, primers, projectiles and a couple pounds of H335 to start rolling my own for it... I need to know whats a good cheap projectile to put thru it for just general plinking? (1:7 twist)

 

[henschman]

Nice... but you have your rear sight on backwards! You want the aperture as close to your eye as possible.

That should be a great rifle for you. You should roll about 400 rounds, put a GI web sling on it, and bring it to an Appleseed: www.appleseedinfo.org

 

[cowtownup]

LOL.. Thanks for helping me out there.. I actually have an Appleseed event about 2 hours away in Ramseur, NC.. I've been looking into it...

 

[heavydluxe]

I need to know whats a good cheap projectile to put thru it for just general plinking? (1:7 twist)

Parallel lives, dude... My first centerfire rifle was a PSA built, similar to yours. And, I'm now starting to get into reloading as a way to shoot more (with 4lbs of H335 sitting downstairs waiting to start going BANG).

When you mention projectiles, I'm assuming you mean it literally in the context of reloading. I've found that the Hornady 55gr FMJBT bullets are readily available and are usually pretty inexpensive. For example, Midsouth Shooter's Supply was selling 250 of them for $23 and change (which comes out to just about $.09/bullet). You can buy them in more quantity and save a little, but even at that price they're pretty reasonable.

There are also sites that sell pulled bullets (like Rocky Mountain Reloading), but I've not found anywhere for less than I can find the Hornadys.

Moreover, I've read in a few different places that people who reload have had really good luck with the Hornady bullets in terms of consistency of 'construction' and getting them to perform well.

Hope that helps.

 

[cowtownup]

I appreciate that information.. I saw the Hornday FMJ with cannelure the other day for $50 per 500.. I knew it was a good deal, but I've never loaded bullets with a cannelure. Are those the same bullets you are referring to?

 

[horsemen61]

I just built a PSA rifle myself nice gun btw

 

[heavydluxe]

Yes, the exact same... see the link in my previous post (the Midsouth link).

I think the general idea is just that you seat the bullet to a depth where the top of the case mouth lines up in the cannelure and then you can crimp the case neck to hold the projectile more securely.

I've also been told, however, that most people agree that crimping a bullet is mostly optional when loading for an AR15 (firing semi auto). The neck tension itself should be enough to hold the bullet securely in most cases.

 

[Onewolf]

I appreciate that information.. I saw the Hornday FMJ with cannelure the other day for $50 per 500.. I knew it was a good deal, but I've never loaded bullets with a cannelure. Are those the same bullets you are referring to?

The Hornady 55gr FMJBT is favorite plinking bullet. The boat tail allows you to seat bullets without requiring the additional neck mouth widening step needed to efficiently seat flat base bullets.

My buddy had been talking about buying an AR for several months and he was looking at low end Bushmasters/etc. I talked him into a PSA blem lower and PSA flat top (Midwest) upper and he is EXTREMELY happy with the rifle.