Hey Guys

WOW after signing up a million years ago  and forgetting about this site , ( how is that possible right ) this is my first post here.

Ordered a Quarter Circle 10 9mm colt  lower other day and am trying to put together a build list to complete it.  I also have a Liberty Mystic X ordered and will be using on this.   Here is what I am thinking of going with so far.  

-Adco's 4.5" barrel

-RRA's A4 9mm upper receiver

-JP's JPBC-9MMA enhanced 9mm bolt ( states it is compat with Colt smg-style and Glock mags, emailed them and they say it is ramped )

-JP's JPSCS-9mm silent captured spring - Any one have experience this bolt and buffer spring ?  Ultimate goal is have quietest combo possible, but dont want to suffer in reliability of course  Also thought maybe using RRA ramped bolt from Adco and using a diff buffer and spring . Had recommendation of a Vltor A5H4 buffer or a heavybuffers.com 9mm-Q Buffer with wolf spring ?  I see that one weighs in at 8.5oz . Not sure how what the JP silent spring weighs in at ?

-Still looking at different handrail options. Prob a 9" hand rail. My suppressor will be 8" without the barrel adapt ( 1.375" in dia) . Should I look for the largest dia hand rail so I get less heat buildup on the rail. Sounds like heat isnt a issue.

-Magpul ctr stock

-also will need a flash can of some sorts till I get the can to get it out past my handgaurd.  

Still trying to figure out my lower parts kit deals out there,  also need to  find a decent trigger that I can use ,  I heard that some multi-stage triggers that have rounded hammers have issues?   Just want to be sure I get all my specs right before I start placing my orders for all this.

Thanks for any help
Bob

2003 join date and this is your first post?!  Welcome!

That looks like a good list of parts you have.  I also used the RRA 9mm upper.  I know it's more expensive, but I really couldnt find any other dedicated 9mm uppers.

Here is a picture of mine with a 9" rail.  4.5" Adco barrel and Octane 9.

Hi Edcurtis

That is a sweet looking setup,   Yah can't believe its been that long since I did sign up.  Just recently acquired  a 300 blackout pistol with a 10 1/2" barrel that peeked my interest to do a SBR 9mm build.  That led me to this site and finding out I was already signed up
IF you dont mind what buffer and spring are you running in your setup and what rail is that ?    THat is the exact look I am shooting for in my build. ALso any issues with your build and how does it run.  
Thanks
Bob

I am using a Spikes ST-9X buffer (8.5oz)  $49.95 from AIMSurplus.  At first I was using a standard carbine spring and the rifle was perfect.  Then I decided to try a Wolff Extra power spring and it's still perfect.  So I'm not sure it really helped anything.

I know a lot of people like the JP stuff, but I was also trying to save a little more to put towards other things.  Since you will only be using Colt mags, no need to really get a bolt cut for Glock.  A CMMG ramped bolt would be a little cheaper.  As well as a Spikes buffer.  But that's just my opinion.  But I guess if it's more "silent" and that's what you want, maybe you should try it.  

The rail is a Samson Evolution.

I love the ALG ACT trigger in mine. Awesome first post and welcome.

I have a similar setup to what you're building. DDLES Colt style lower and Sun Devil slick side upper with an Adco 4.5" barrel.  I have the JP BCG and silent spring too, it cycles very smoothly and has very little recoil.  So far it's been flawless with all kinds of ammo, supers and subs. It is shot 100% of the time suppressed with an Octane 45.

Thanks so much for the info.  It is greatly appreciated

Edcurtis & Dvp18  - What lower parts kit  and triggers are you guys running in your setup?  

Thats good to hear the Jp bolt and Silent spring are working good,  it seems like alot of $$ but my ultimate goal is to get it as quiet as possible.  I assume you all are just running standard mil-spec buffer tubes ( or receiver extension, technically ) ? I suppose a buffer tube is a buffer tube, besides commercial vs mil spec

What was suppose to be just a slow build, buy a part hear and there seems to be gotta get built now lol .  Hope the wife doesnt see the receipts

Was also wondering are there  issues with gas blowing back in the face when running a can on a setup like this.  Saw a few posts of ppl using the PRI gas busting charging handles  or something about a RTV trick.   Thought about even maybe a side charging uppers would maybe help, but seems they would be considerably louder even the non-reciprocating kind.

Don't recall what brand of LPK I used, but it was nothing special and it just has a standard mil-spec FCG.  There is a good bit of gas blowback out of the ejection port, but it's not terrible and the gas deflector helps a good bit.

I'm using a standard Palmetto Armory parts kit.... I want a fancy trigger but haven't decided yet.

DDLE lower
CMMG 9mm dedicated upper
Colt LPK
ALG Defense QMS trigger
Tango Down BG-16 grip
Metalform Colt pattern 32rd magazine
Heavy Buffer six position mil-spec receiver extension
Heavy Buffer 9Q-T (Tungsten) 12 oz. buffer (full time suppressor)
Wolff XP spring
Impact Weapons Components rotation limited QD end plate
Yankee Hill Machine diamond series 9.675" Specter Length

Waiting on:
Green Mountain 9mm barrel cut to 5.75"
CMMG 9mm bolt
AAC TiRant suppressor
Norgon Ambi-catch
B5 stock
Troy sights

HK416 Sights
VLTOR MUR Upper
Adco 5" Barrel
Chopped Wilson Combat TRIM
Wilson Combat TRIM Vert Grip
KAC URX 3 Hand Stop
PRI Gasbuster

QC10 Lower
Troy Battle Grip
LWRC Ultra Compact stock

Missing the JP Glock bolt and Slash's heavy buffer for the LWRC stock.

Russell Athletic

How did you get the TRIM rail cut down?  Love that look.

Hack saw . Clean it up with a file and then some Birchwood Casey black.