9mm AR SBR

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briansbr44
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9mm AR SBR

Post by briansbr44 » Sun Mar 06, 2011 7:14 pm

I am sure this has been asked alot but I want to puchase a short 7" to 10.5" Upper for my registered lower. What is the best one? What is the best magwell block? In conjunction what are the best mags 32 rd preferable. I would like to not have to change my hammer but don't mind changing out the buffer if necessary. Help want to order one soon but keep getting more confused the more I read. Would also like to keep the cost below $1000 for everything including 7 mags or so.
Thanks

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redtazdog
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Re: 9mm AR SBR

Post by redtazdog » Sun Mar 06, 2011 8:14 pm

A hahn magwell block is one of the best as I have 4 of them and they all work good, one of them is the first model that
Hahn made and it has never failed me. http://hahn-precision.com/AR-15_c11.htm I think Brownells has them too.
Or you can get a dedicated 9mm lower like one of these http://cmmginc.secure-mall.com/shop/ind ... =1&cat=101
I dont know how good the Spikes magwell blocks are but I do know that the Cproduct block is not the best.
The Metalform mags are the best as they made them for Colt, Spikes and other venders have them. http://www.spikestactical.com/new/z/9mm ... 68_87.html
Get a ramped bolt and it will cycle smoother and you can use a normal hammer. http://cmmginc.secure-mall.com/item/CMM ... -Bolt-1320
Many barrels out there to decide on, do you want one with the 3 lugs like the Tros http://www.trosusa.com/
or a barrel with muzzle threads http://www.rockriverarms.com/index.cfm? ... ory_id=243

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schnitzeraffe
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Re: 9mm AR SBR

Post by schnitzeraffe » Sun Mar 06, 2011 9:00 pm

I use a Spike's magwell block and love it.

It is adjustable and, as such, took a little fiddling with it's first time of use to find the "sweet spot".

Since then it has run like a top.

I use 32 round Cproducts and modified UZI mags. No issues with either.

I use a ramped bolt with a normal "un-notched" .223 hammer and a 9mm buffer for all calibers.

My 9mm upper's barrel started life as an unused surplus Colt Department of Energy heavy machine gun barrel.

It was cut down to 7" and threaded 1/2-36.

briansbr44
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Re: 9mm AR SBR

Post by briansbr44 » Sun Mar 06, 2011 9:36 pm

Thanks good info so far. Can someone explain what you have to do to modify the UZI mag for these blocks? Does anyone feel the Spikes Tactical uper is better or the same as say CMMG.
As far as the barrel goes I will go with the standard style w/o the three prong and plan on being able to use a standard 9mm supressor or a 45 TiRant with the 9mm piston. Any advice on possible problems is appreciated.
Thanks again

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chrismartin
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Re: 9mm AR SBR

Post by chrismartin » Sun Mar 06, 2011 9:56 pm

Uppers are uppers really. Barrel and upper receiver. I personally think spikes has put more into their uppers than others recently. Evident with them coming out with their own lowers, mag blocks, magazines, buffers, bolts etc.

Issues that you will run into will be failures to load, eject, etc. If you search here these topics have been covered a bunch and there is or was a sticky in the ar15 section. Usually easy to fix but tedious. Adjusting you ejector will be the problem 99% of the time for fte's. Other issues will be mag related (get the spikes mags first, then if needed try c products or pro mags) at this point I'd just get the metalform spikes mags. Cdnn has metalforms.

Get a ramped bolt and a spikes heavy or other 9mm buffer.

There is or was a video on YouTube on modifying Uzi mags. Basically you just dremel a new mag catch slot for the ar. Bolt hold open function will not work however.

http://www.youtube.com/watch?v=HoSLgZIGxFA
Last edited by chrismartin on Sun Mar 06, 2011 10:06 pm, edited 1 time in total.

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schnitzeraffe
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Re: 9mm AR SBR

Post by schnitzeraffe » Sun Mar 06, 2011 10:03 pm

chrismartin wrote:There was a video on YouTube on modifying Uzi mags. Basically you just dremel a new mag catch slot for the ar. Bolt hold open function will not work however.
I prefer my Cproducts mags over my UZI mags because of the bolt hold open issue.

I have also seen vids on the home brew Dremel UZI mag mod, but personally preferred to have mine done by a pro.

M60 Joe is my go-to guy:

http://users.zoominternet.net/~picplace ... z_mags.htm 8)

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Libertarian_Geek
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Re: 9mm AR SBR

Post by Libertarian_Geek » Sun Mar 06, 2011 10:34 pm

I use this lower:
http://www.shop.doublediamondsupply.com ... 9mm_c7.htm

Standard upper (DPMS, I think).
Spikes 9mm Buffer
CMMG Ramped 9mm Bolt
Spikes 9mm 5" barrel
SWR Trident 9

It runs like a champ.

Modified UZI mags. (I used a mill to notch them after removing the bolt-catch and marking them through the hole.)
C-Products mags. Run great and trip the bolt-catch.

I did have a CMMG lower and a DPMS slick-side flat top upper. I'm not sure which was the problem, but I had feeding problems until I switched both. I didn't switch them independently, so I can't attribute the problem to one or the other.
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8th SPS USAF
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Re: 9mm AR SBR

Post by 8th SPS USAF » Wed Mar 09, 2011 4:26 pm

RRA makes a deticated 9mm lower. I made my SBR from one. C products works great.
Even Pro Mag 9mm Ar mag works. If you have a semi auto SBR 9mm , why do you need
a ramped bolt? Mine works fine, but not FA. Thank you

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schnitzeraffe
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Re: 9mm AR SBR

Post by schnitzeraffe » Wed Mar 09, 2011 8:23 pm

8th SPS USAF wrote:If you have a semi auto SBR 9mm , why do you need
a ramped bolt? Mine works fine, but not FA. Thank you
The Colt style 9mm bolts (including RRA) are designed to be used with a dedicated 9mm hammer.

An M16 hammer (or un-notched AR hammer like a DPMS) will work with these bolts as well, but there is a great deal of added stress on the FCG.

Ramping the bolt increases the length of travel before the hammer is completely reset and reduces some of that stress which should increase the life of your firearm.

It also reduces the possibility of a jam. I've seen such a malfunction with a notched AR hammer (like RRA) and an unramped bolt.

Not pretty. It was almost impossible to get apart.

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