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jhj32883
06-13-2012, 5:28 PM
Hello All,

I'm considering building an AR 308. Being the newb that I am, I want to purchase a complete upper. I would like an upper with a flat top receiver w/ picatinny rail, 20" barrel, direct impingement and free float handguard.

Also, I would like to spend in the ballpark of $700-$900. However, if there's something cheaper and of good quality, I'll totally take it.

Does someone offer a complete upper that matches what I'm seeking?

I was also wondering if I could take an A2 style upper and ditch the A2 carry handle, front sight assembly and handguard. I found one at DPMS:

http://dpmsinc.3dcartstores.com/20-308-Barrel-Assembly_p_160.html

I was thinking that I could just ditch the front sight assembly and replace it with a gas block. I assume I would use the .936 Micro or low profile gas block as the barrel is heavy contour and I would like to run a 13"+ hand guard over it. Would this work?

Also would I need a new gas tube if I went with just a gas block?

Can I just remove the A2 style carry handle? The description says it's an A3 flat top receiver. Will it have a picatinny rail under it or would I need to purchase one to make it a flat top receiver?

Also, does being an A3 receiver create any issues? I would like to have a full continuous rail at 12 o'clock (I don't like the look of a gap between the receiver and the barrel assembly). If the A3 receiver has a pic rail, will it match the pic rail if I go with quad rail hand guard?


Thanks in advance for the info.

Jay

Hoop
06-13-2012, 6:29 PM
JSESurplus has some regular 20" DPMS HBAR uppers for sale. You could get one of those and then buy some rifle length quad rail handguards and have a smith swap them out for you.

If you are a do it yourselfer you can build your own. They aren't difficult. You could assemble what you want for yourself for about 900.

1Luv4SF
06-13-2012, 9:36 PM
An A3 receiver always has a rail on top so you can just unscrew the carry handle and there it is. As for the handguard I recommend the Troy MRF 13.8. It's uninterrupted meaning there will be no gap between it and the upper receiver. Here's my 308 with the Troy MRF and 24" barrel to give you an idea.
http://img.tapatalk.com/c6e4d4e7-7840-c49e.jpg

1Luv4SF
06-13-2012, 9:37 PM
Sorry I don't know why that pic came out so hazy. It's clear on my iPhone.

jhj32883
06-14-2012, 7:22 AM
JSESurplus has some regular 20" DPMS HBAR uppers for sale. You could get one of those and then buy some rifle length quad rail handguards and have a smith swap them out for you.

If you are a do it yourselfer you can build your own. They aren't difficult. You could assemble what you want for yourself for about 900.

Hoop,

Thanks for the heads up. I think I'm going with the DPMS 20" HBar .308 Classic Factory Built Upper Receiver Complete Upgraded / Fluted. It doesn't have the carry handle so I guess one less thing to do.

Also, I assume I have to buy a low profile gas block in .936 because the upper has a heavy barrel and I want to put a free float tube on it.

If I purchase a complete upper, do I still need to check head space? That's pretty much why I wanted to purchase a complete upper as I don't have any of the gauges and would rather trust my face and well being to the professionals.

Jay

jhj32883
06-14-2012, 7:29 AM
An A3 receiver always has a rail on top so you can just unscrew the carry handle and there it is. As for the handguard I recommend the Troy MRF 13.8. It's uninterrupted meaning there will be no gap between it and the upper receiver. Here's my 308 with the Troy MRF and 24" barrel to give you an idea.
http://img.tapatalk.com/c6e4d4e7-7840-c49e.jpg

1Luv,

I like the Troy MRF 13.8. I was wondering about the proprietary Troy barrel nut though. Would I need to purchase the Troy DPMS Barrel nut separately?

Jay

Also, does the A3 Upper take the High Profile or Low Profile rail? I'm assuming it's the High Profile Rail.

Thanks

1Luv4SF
06-14-2012, 1:07 PM
It comes with the barrel but. Also DPMS .308 uppers come in 2 rail heights. High profile and low profile so make sure when you buy the rail your getting the right one. They always list on the websites as either HP or LP. Also, you do not need to headspace the barrel for an assembled upper. Especially from a reputable company like DPMS. Generally most most all barrels sold by themselves are already headspaced.

1Luv4SF
06-14-2012, 1:08 PM
Meant to say that the Troy MRF rail comes with the barrel nut.

lwbyo1
06-14-2012, 2:06 PM
Welcome to the forum Jay.

Your upper will be the "Low Profile". All DPMS A3 uppers made after late 2009 are the low profile height.

That upper has a standard A2 front sight tower, so you'll need a .750 diameter gas block. I would recommend a low profile clamp on gas block instead of one with set screws, unless you're going to drill dimples in the barrel.

The MRF rails are nice, but they're heavy. The TRX rail is about 3/4 of a pound lighter and would be something to consider. The TRX has a continuous rail also. Both rails should come with the barrel nuts.

Since the upper was factory assembled, the headspace should have been checked at the factory. So you're GTG.

And yes, you can reuse the gas tube.

jhj32883
06-14-2012, 5:34 PM
Welcome to the forum Jay.

Your upper will be the "Low Profile". All DPMS A3 uppers made after late 2009 are the low profile height.

That upper has a standard A2 front sight tower, so you'll need a .750 diameter gas block. I would recommend a low profile clamp on gas block instead of one with set screws, unless you're going to drill dimples in the barrel.

The MRF rails are nice, but they're heavy. The TRX rail is about 3/4 of a pound lighter and would be something to consider. The TRX has a continuous rail also. Both rails should come with the barrel nuts.

Since the upper was factory assembled, the headspace should have been checked at the factory. So you're GTG.

And yes, you can reuse the gas tube.

lwbyo1,

Thanks for the welcome and the information.

You were definitely spot on about the .750 diameter gas block.

You alluded to a clamp on gas block. Does DPMS make one? I searched DPMS' website and could only find the Micro .750 Gas Block with the set screws. If they don't make one, can you suggest one?

Jay

AAShooter
06-14-2012, 5:39 PM
Hello All,

I'm considering building an AR 308. Being the newb that I am, I want to purchase a complete upper. I would like an upper with a flat top receiver w/ picatinny rail, 20" barrel, direct impingement and free float handguard.

Also, I would like to spend in the ballpark of $700-$900. However, if there's something cheaper and of good quality, I'll totally take it.

Does someone offer a complete upper that matches what I'm seeking?

I was also wondering if I could take an A2 style upper and ditch the A2 carry handle, front sight assembly and handguard. I found one at DPMS:

http://dpmsinc.3dcartstores.com/20-308-Barrel-Assembly_p_160.html

I was thinking that I could just ditch the front sight assembly and replace it with a gas block. I assume I would use the .936 Micro or low profile gas block as the barrel is heavy contour and I would like to run a 13"+ hand guard over it. Would this work?

Also would I need a new gas tube if I went with just a gas block?

Can I just remove the A2 style carry handle? The description says it's an A3 flat top receiver. Will it have a picatinny rail under it or would I need to purchase one to make it a flat top receiver?

Also, does being an A3 receiver create any issues? I would like to have a full continuous rail at 12 o'clock (I don't like the look of a gap between the receiver and the barrel assembly). If the A3 receiver has a pic rail, will it match the pic rail if I go with quad rail hand guard?


Thanks in advance for the info.

Jay

Personally, I think your price goal is pretty aggressive. I think something in the $900 - $1000 will get you a decent low end .308. The one I just built ran about that.

jhj32883
06-14-2012, 5:50 PM
Personally, I think your price goal is pretty aggressive. I think something in the $900 - $1000 will get you a decent low end .308. The one I just built ran about that.

AA,

Is DPMS of poor quality or performance? Nothing I've researched would indicate as such. However, I am a complete newb and have no personal experience with DPMS.

I did a quick calculation of what I would want in a complete upper half and I want to go with a DPMS complete upper with some mods. It came up to just under $1,000.

Jay

1Luv4SF
06-14-2012, 6:02 PM
He was confused. He thought you wanted to build an entire .308 rifle for $900. Your budget is for the upper from what you said. And no worries DPMS is a great manufacturer. My upper and barrel is DPMS and it's incredibly accurate.

AAShooter
06-14-2012, 7:14 PM
I am with 1Luv4SF. I thought you were talking about a complete rifle for $700 - $900. I have this upper: http://www.brownells.com/.aspx/pid=26619/Product/LR-308-Upper-w-18-CM-Bull-Barrel

I haven't shot it so don't have much info for you.

I still have an eye on some of these: http://www.fulton-armory.com/FAR-308-Complete-Uppers.aspx

Of course, everything goes sidewise once you start looking at some serious optics. :D

weber_2
06-14-2012, 8:00 PM
I wouldn't recommend a 308 for a noob, go 556. Unless money ain't a thang!

lwbyo1
06-15-2012, 1:07 AM
lwbyo1,

Thanks for the welcome and the information.

You were definitely spot on about the .750 diameter gas block.

You alluded to a clamp on gas block. Does DPMS make one? I searched DPMS' website and could only find the Micro .750 Gas Block with the set screws. If they don't make one, can you suggest one?

Jay

Any low profile AR15 .750 gas block should work. YHM, Vltor, Daniel Defense, Syrac. That's just a few I can think of right now, I'm sure there's a few more I'm forgetting about.

jhj32883
06-15-2012, 10:28 AM
I wouldn't recommend a 308 for a noob, go 556. Unless money ain't a thang!

Weber,

I already have a 5.56.

I wish money weren't a thang!

Jay