My pistol-sbr plan. Any advice or compatibility issues *update with completed build and ftf issues

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[ARCHIVED THREAD] - My pistol-sbr plan. Any advice or compatibility issues *update with completed build and ftf issues

Posted: 3/21/2017 10:42:06 PM EDT

Just wanted to run my new plan for a build by some more expert opinions. This will be my first full build. I'll build a 9mm ar pistol first, and will probably convert to sbr in the future.

Here's the parts that I'm looking at. But suggestions and criticism is good too.

- matrix arms side charging upper and lower glock mags
- Odin works 9mm 10.5 barrel
- kaw valley blowback bcg
- Midwest handguard 10" G3
- aimpoint comp (I have one laying around already)
- Anderson fcg (also already have)
- shockwave
- kak 9mm buffer

Is everything in this list good to go? I've never bought anything from kaw valley, matrix, or Odin works.

What would you change?

Posted: 3/22/2017 3:50:42 AM EDT

[#1]

Why 10.5? I'd go shorter if you plan to supress and run subsonic ammo.

Otherwise, OdinWorks makes great barrels(I haven't used their 9mm). I used the kaw valley bolt in my side charged SBR and works fine.

Posted: 3/22/2017 5:03:06 AM EDT

[#2]

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Quoted:
Why 10.5? I'd go shorter if you plan to supress and run subsonic ammo.

Otherwise, OdinWorks makes great barrels(I haven't used their 9mm). I used the kaw valley bolt in my side charged SBR and works fine.

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As he said, 10.5 is a little long. But it's your choice.

When I did mine I ended up 8.5". I basically looked at the average of every major smg and figured 8"-10" was it with there really being no benefits to longer. In retrospect, I probably should have gone 7.5, but I am happy.

That said, get a hand stop, even 8.5" will have you checking your finger tips once or twice. It very easy with a pistol build to find your forward hand sliding towards the muzzle.

Posted: 3/22/2017 5:03:41 AM EDT

[#3]

dbl tap

Posted: 3/22/2017 6:50:33 AM EDT

[#4]

Id make sure you comp is big enough for 9mm and has the right thread pitch for your barrel.

Posted: 3/22/2017 9:13:12 AM EDT

[#5]

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Quoted:

As he said, 10.5 is a little long. But it's your choice.

When I did mine I ended up 8.5". I basically looked at the average of every major smg and figured 8"-10" was it with there really being no benefits to longer. In retrospect, I probably should have gone 7.5, but I am happy.

That said, get a hand stop, even 8.5" will have you checking your finger tips once or twice. It very easy with a pistol build to find your forward hand sliding towards the muzzle.

Other than that, it all looks good. I went Thordsens brace, and used a Vltor A5H4 buffer to eliminate any spacers or issues.

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Can we see a pic?

Posted: 3/22/2017 10:37:57 PM EDT

[#6]

Thanks. Going by ballistics by the inch site, it seems like there's a drop off just past 10 inches and about 9 inches is the very best around that range. Difficult to find 9 inch barrels but I've decided on an 8.3 inch from Ballistic advantage. Seems like a good compromise.

Posted: 3/22/2017 10:42:40 PM EDT

[#7]

I have no experience in short barrels. The 5.56mm as designed by Stoner, was brilliantly for 20" to burn all the powered etc..
What type of blast/flash do you get below 10"??? Shouldn't a 5.56mm be designed for this barrel length?

Posted: 3/23/2017 3:22:46 AM EDT

[#8]

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Quoted:
Thanks. Going by ballistics by the inch site, it seems like there's a drop off just past 10 inches and about 9 inches is the very best around that range. Difficult to find 9 inch barrels but I've decided on an 8.3 inch from Ballistic advantage. Seems like a good compromise.

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That what I did... Plus looked at the average length of a bunch of SMGs which were all 8-10 with about 8.5-9 the average. I ended up with the CMMG 8.5, which I really like.

Posted: 3/24/2017 1:00:44 AM EDT

[#9]

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Quoted:

Can we see a pic?

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Sorry, the sling kinda got in the way. Basics are a slick side upper, BCP EF9 Lower, UTG Super Slim 7", put the TLR on it and some Midwest Industies SS panels fit perfect(just used the UTG screws). You can't see it well, but the front HK sling mount is a Samson mounted through one of the vent slots. IIRC, overall is 23.5" as she sits. Haven't decided on a muzzle device yet, either a tri-lug adapter or an AAC Blackout. Over the last year or so she has had about 3000 rds through her. Barrel loosened up at about 2700, but I chalk that up to having a buddy do the torque for me and he was a little leery of the wrench. It's a ball to shoot!!

Posted: 3/24/2017 11:56:42 PM EDT

[#10]

+1 on 10.5" being too long for 9mm. I went 4.5"... not much real estate on that 4" handguard. But if we're going short, let's go short!
9mm does not have the same velocity concerns as 5.56, but I can understand going a little longer for comfort's sake.

Edit: Still trying to figure out how to post images. Seems to be a common PITA.

Posted: 3/25/2017 8:40:58 AM EDT

[#11]

"Haven't decided on a muzzle device yet" You may like the new MI blast can.

Posted: 3/25/2017 12:22:23 PM EDT

[#12]

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"Haven't decided on a muzzle device yet" You may like the new MI blast can.

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I like the idea of a blast can and I'm a fan of MI

But I'm thinking it might look kind of weird unless the barrel is covered by the handguard. I have a 7" handguard and a 8.3 inch barrel. I'll have to see how it looks when I get the parts delivered and can mock it up

Posted: 3/25/2017 1:06:06 PM EDT

[#13]

I agree, maybe a 9" or even 10" handguard would look better and cover some of the blast can (3.375" long)

Posted: 3/26/2017 10:53:58 PM EDT

[#14]

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Quoted:
I agree, maybe a 9" or even 10" handguard would look better and cover some of the blast can (3.375" long)

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Well I just realized I probably made a mistake ordering a Midwest gen3. It has anti rotation tabs and might not work with the new frontier upper which is a bit different than mil spec.

If that doesn't work I'll probably go that way

Posted: 3/27/2017 2:56:41 AM EDT

[#15]

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Well I just realized I probably made a mistake ordering a Midwest gen3. It has anti rotation tabs and might not work with the new frontier upper which is a bit different than mil spec.

If that doesn't work I'll probably go that way

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Can confirm, it won't work.

Posted: 3/27/2017 7:58:49 AM EDT

[#16]

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Quoted:

Can confirm, it won't work.

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Quote History

Quoted:

Can confirm, it won't work.

Damn, I saw this in the Midwest industries picture page and got my hopes up. May have to ask him how he did it

Quoted:
New Frontier/Joe Bob's upper and lower.
Faxon 8.5 9mm barrel
MI 7.25" G3 MLOK Handguard
KAW Valley bolt, buffer and spring
Mil spec trigger
Troy BUIS
Magpul furniture

http://i1298.photobucket.com/albums/ag53/MSUbulldog21/Guns/9A9DFD87-9ABA-411C-87CD-52DADCE648E8_zpskurmxtw2.jpg
http://i1298.photobucket.com/albums/ag53/MSUbulldog21/Guns/BE815A8A-1224-4BCF-BDFA-54238810EC1C_zpsrskcg5uw.jpg

Close fit

http://i1298.photobucket.com/albums/ag53/MSUbulldog21/Guns/8045B1A1-217F-4F5D-A0D8-FF6CBA9219B9_zpsao1997qr.jpg

https://www.ar15.com/forums/t_2_176/217879_Midwest-Industries-Inc--Picture-Thread----Show-off-that-MI-gear-.html&page=3

Posted: 3/27/2017 9:33:47 AM EDT

[#17]

Here is my 5.5" barrel with a 7 something inch SLR rail on it and a KAK Flash Can

Attached File

Posted: 4/1/2017 12:19:32 AM EDT

[#18]

Got it mostly together today.

The Midwest handguard worked fine, but I made the mistake of tightening screws on the anti rotation tab too tightly before putting it on. Made it a bitch to slide up on the barrel nut.

Seems like everything is working alright, won't get to shoot it for awhile though.

Only things left to do is add a handstop, three lug adapter, and get some rounds through it

Posted: 4/8/2017 4:58:52 PM EDT

[#19]

Finally got it out today shooting. Very accurate, but every once in a while I get a jam, where the bullet nosedives and doesn't make it into the chamber.

For some reason it happens more with factory glock mags. The ets magazine actually runs a lot better but it still happens sometimes with that one too.

Any ideas?

I've tried playing with the ejector/mag stop height, thought maybe it was set too low but any higher and the bolt doesn't clear the ejector. Not having any ejection problems though, and the primer strikes are hitting right where they should.

Other than that it was a lot of fun. So easy to shoot at cqb distances. Just needs a little work and a lot more rounds through it before I can trust it.

Posted: 4/9/2017 10:28:51 PM EDT

[#20]

Pic of chamber mouth????

Posted: 4/9/2017 11:18:52 PM EDT

[#21]

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Pic of chamber mouth????

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I will be taking it off soon, will take picture then. I'm going to replace it with a faxon barrel. Reading up on it, it seems people have had better luck with those.

Posted: 4/10/2017 6:22:25 AM EDT

[#22]

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I will be taking it off soon, will take picture then. I'm going to replace it with a faxon barrel. Reading up on it, it seems people have had better luck with those.

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You might just need to have a little work done to the chamber mouth. No reason to replace the whole barrel.

Posted: 4/10/2017 7:57:20 AM EDT

[#23]

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Quoted:

I will be taking it off soon, will take picture then. I'm going to replace it with a faxon barrel. Reading up on it, it seems people have had better luck with those.

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We've been spending a lot of time and effort on those critical ramps!

Posted: 4/12/2017 12:37:25 PM EDT

[#24]

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Quoted:
Pic of chamber mouth????

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Not the best quality photo, but at least you can see where the bullets are impacting the feedramps.

I'm going to give BA a chance to make it right, but I'll be putting on the faxon that I just got too. The feed ramps on this one looks much better.

Posted: 4/20/2017 11:29:28 AM EDT

[#25]

Switched the barrel to faxon and changed to a heavier 10 oz kak buffer. Also switching over to hst 9mm instead of gold dot. Seems to be feeding better just dry testing, but still jams up occasionally. Much less than the BA, but it's not perfect still

Now I have developed a problem with glock mags locking back with one round still in the magazine. Seems like the hook is getting pushed up by the follower underneath. Weird that it wasn't doing this before and I've made no changes to the lrbho system. Not sure what to do with that yet.

Over all I'm having much better luck with the clear ets mags. They have a shallower angle to the feed lips than oem glocks, I think that helps. But then again, the standard capacity 17 mags work the best. Haven't had a jam with one of those

I have decided that I will NOT sbr. The shockwave is actually way more comfortable than I thought. Ringing steel up to 25 yards was effortless

[ARCHIVED THREAD] - My pistol-sbr plan. Any advice or compatibility issues *update with completed build and ftf issues

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