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Thinking of building a 9mm AR

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I've been reading up on ar15.com about different 9mm options and I think I'm going with the magwell insert for modified uzi/colt mags option. It looks like most of the magwell inserts run $150-$200 except for promag. They make an insert that goes for $40. I'm wondering if anyone has experience with building up an AR along this route or had any input on the promag insert. Also wondering if there's any 15rd mag option for this route. I think the colt smg mag is available in a 10rd but I believe the only other option is 32rd.

I have never seen a ProMag product that was worth the money paid for it. I have owned several magazines from them and they were garbage. Their other products do not get any better reviews online. Please use some Google before you throw away money on ProMag.

The promag adapter is a flaming pile of shit. Actually just threw mine in the garbage today. Don't wast your money. I picked up a spikes for 135 ish a few mnths back. Haven't fired it but just manually cycling it shows a huge improvement. It actually feeds!

I have never seen a ProMag product that was worth the money paid for it. I have owned several magazines from them and they were garbage. Their other products do not get any better reviews online. Please use some Google before you throw away money on ProMag.

 

Agreed, it's hit or miss with their products. And of course for me it's been misses.

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The promag adapter is a flaming pile of shit. Actually just threw mine in the garbage today. Don't wast your money. I picked up a spikes for 135 ish a few mnths back. Haven't fired it but just manually cycling it shows a huge improvement. It actually feeds!

 

That's what I needed to know. Thanks. What mags do you run and where'd you get them?

I e been using stoner and cproducts 10 rnd mags from midway. Colt smG style.

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What do you want for the buffer? I'm keeping my eye out for different options which include "kits" which include the buffer so I'm not sure if I'll need it yet.

If its going to someone who is actually gonna use it you can have it for free.

 

I wouldn't just give it away to someone who wants free parts they won't use though.

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cool, I have a complete lower so the build is definitely happening. Not sure how I'd meet up with you though, you're in salem county?

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I live in New Egypt about 10 minutes from great adventure.

Like freejersey, i also have a Double Diamond glock lower and its truly a work of art. For the cost of a new lower plus a mag block, you can buy a DDLES glock lower for the same money. Of course, if you are trying to re-purpose an existing lower, then the retrofit makes more sense financially. Also, a 9mm lower will only ever be a 9mm lower, you can never convert it back to shoot 223 or any other rifle caliber so you lose that utility. The DDLES lower does have some advantages over the magwell conversions in that it will lock back on the last shot and Glock mags are far more abundant, reliable and inexpensive. It should also be disclosed that using glocks mags with a 9mm AR bolt will require some extra machining on the bolt carrier to clear the glock feed lips, so that is another factor to consider. DD also sells a bolt with this modification already performed though so solving this issue is easy unless you already have purchased a 9mm bolt. The upside is that they also provide the proper ramp angle on the 9mm bolt that, for some reason, most bolts aren't produced at the factory with. These are some of the things that i found when spec'ing out my build and what led me to the DDLES lower.

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I am going the 223/magwell insert route as I already have a complete lower that I traded for. Yeah the magwell block is going to cost more than a dedicated lower but I'm working with what I've got. I also will probably pick up another 5.56 upper at some point to have that option as well, as I'm selling my 5.56 AR to a buddy to fund this and have a few extra bucks. I have my eye on a hahn or spikes mag block. Is there any advantage to going with the bottom loading hahn over the top loading? More permanent/secure fit?

 

I'm seeing 1/10 twist and 1/15 twist rates on barrels. Am I going to be ok shooting 115/124 grain rounds in a 1/15?

http://www.model1sales.com/index.cfm?fuseaction=category.display&category_id=304 I'm guessing these are bottom of the barrel quality but it seems like a decent route to get it up and going and worry about other upgrades later. I want to go with a lightweight barrel profile but I'm not sure on the 1/15 rate.

It depends on the particular mag block what the specific pro's and cons are. But generally the bottom load ones will need some pressure tensioning mechanism so they don't fall out and make sure you check it from time to time. Top loaders will insert from the top and simply rest on the receiver and so they cannot fall out. Depending on the model, it may have some implications as to how the bolt hold open works, whether the stocker is retained or a proprietary one is used instead. Some slip in easily, some need the BHO removed, it all depends, but generally i prefer this style and the Hahn comes in this configuration. Hahn makes them all anyways (hahn, RRA and spikes) so they're all well made, just have different features to whatever the brand specifies.

 

Not sure about the twist rate, I never had a selection so i just took whatever i have. Try searching the web for what the Beretta Storm, Keltec, Mechtech conversions, ruger PC9 and other 9mm carbines have as a comparison. I'll have to ask what mine is now that you bring it up.

Well if your down this way I can give it to you in person. If you pm me your address I can ship it to you.

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