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7/8/2017 8:00:24 PM EDT
Really wanting a 9mm, but I'm definitely between torn between a 16" and a pistol/sbr length.

Which did you choose and why?
7/8/2017 8:11:49 PM EDT
[#1]
Im itching for one in the 7" sbr range but biggest thing stopping me is putting in for the stamp.

From what i understand 9mm doesn't need much over 5" or so
7/8/2017 8:13:16 PM EDT
[#2]
I'm in the process of building two uppers.

One is a 10.5" upper, a clone of the colt 635.
So that's why I chose that...I like clones.

Second is a 5.5" upper.  I have a 9" long 9mm subgun suppressor that I plan to bury in the handguard with the barrel.  The barrel and can will come out to 14", and I'll do a 10" hanguard over it.

These will both be used on a colt m16 lower.

So those are what I chose and why.  HTH
7/8/2017 8:56:11 PM EDT
[#3]
If you're in a state that lets you have AR pistols, I say the current best option is a 9mm pistol with a brace because we can shoulder them now.  Build one of those and you can always file the form1 on it later.  And if you do a pistol first, you are allowed to flip flop that lower receiver back and forth between a pistol and a rifle.
7/8/2017 9:19:14 PM EDT
[#4]
Quote History
Quoted:
Im itching for one in the 7" sbr range but biggest thing stopping me is putting in for the stamp.

From what i understand 9mm doesn't need much over 5" or so
View Quote
It really depends on what you plan to do with it and the load you plan to shoot in it.

If you're going to suppress it and shoot 147-165 gr sub sonic rounds, a 7" barrel is great.

If you are not going to suppress it, then there is some benefit to a longer barrel.  If you're shooting a load optimized for a 3.5" to 5" handgun with faster burning powder, you won't see much increase - but you'll still get an increase.  However, if you're shooting a hand load with a slow burning pistol powder like Blue Dot you'll see a much more significant increase.

For example I have both a 10.5" (actually 11.125" bolt face to barrel end) pistol and a 16" carbine, and depending on the load, I'll see differences in velocities varying from 110 to 300 fps second.  That's a difference of only 22 fps/inch to a much more significant 60 fps/inch, depending on the bullet and the powder used.    

I have developed loads that launch a 124 gr bullet at over 1,450 fps, as well as loads that will launch a 90 grain bullet at over 1,600 fps in a 16" barrel.   That's at least 300 fps faster than you'd get out of a 5" pistol, and still about 100-150 fps faster than you'd get with a 5" .357 Sig.

In that regard, I have a 16" carbine in order to maximize performance with a 9mm in an AR, and I have a 10.5" pistol, mostly because it's a sweet spot between ballistic performance and slick handling.
7/8/2017 11:13:57 PM EDT
[#5]
Quote History
Quoted:
I'm in the process of building two uppers.

One is a 10.5" upper, a clone of the colt 635.
So that's why I chose that...I like clones.

Second is a 5.5" upper.  I have a 9" long 9mm subgun suppressor that I plan to bury in the handguard with the barrel.  The barrel and can will come out to 14", and I'll do a 10" hanguard over it.

These will both be used on a colt m16 lower.

So those are what I chose and why.  HTH
View Quote
Take a look at our "guaranteed to feed" 9mm barrels...they run awesome on my smg lower.....
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