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M4arc
01-21-07, 10:21
Does the mid length gas system make much of a difference in the 9mm carbines?

I see that ADCO mostly carries the mid length barrels. Now I love mid lengths and I'm interested in building up (or buying) a RRA 9mm but I'm not sure if I want a middy or a CAR length gas system.

LOKNLOD
01-21-07, 10:27
Do 9mm ARs use the gas system? I thought it was blowback operated?

M4arc
01-21-07, 10:28
Do 9mm ARs use the gas system? I thought it was blowback operated?

I have no idea, I just see Mid-Length and CAR systems offered.

LOKNLOD
01-21-07, 10:36
I have no idea, I just see Mid-Length and CAR systems offered.

I think the CAR vs. Mid is only a matter of which handguard length you prefer in 9mm ARs. Unfortunately this is like the blind leading the blind so I should probably shut up until we find a definitive answer on this ;)

Check out the 9mm bolt/carrier at ADCO (upper parts page). No gas key.

M4arc
01-21-07, 10:43
I think the CAR vs. Mid is only a matter of which handguard length you prefer in 9mm ARs. Unfortunately this is like the blind leading the blind so I should probably shut up until we find a definitive answer on this ;)

Check out the 9mm bolt/carrier at ADCO (upper parts page). No gas key.

Yep, I just saw that!

You're right, it looks like it boils down to rail space. However, I also saw the RRA 10.5" upper :eek:

Maybe I'll go ahead and get the lower receiver and send off the SBR paperwork ;)

chrismartin
01-21-07, 11:40
I'm building up a 9mm as we speak.

The 9mm is blowback, not gas operated. I went with a 5.5" TROS 3 lug barrel.
I plan to put carbine length hand-guards for use with my suppressor.
I figure, if I'm going to SBR, I might as well go short :)
The best prices I've found for a lot of the 9mm stuff is ADCO and Rainier.
Also, if you are building your upper, you don't _need_ a 9mm upper, but it will help with the gas blow back, especially if you are a left handed shooter. The 9mm upper has the gas block half-moon thing on it.

My build will be:

LAR Giz lower (SBR'ed lower)
RRA upper
TROS 5.5" bbl
Magpul CRT stock
probably YHM hand-guards, but I haven't decided yet.

Chris

Dport
01-21-07, 12:16
My Colt 9mm is blowback operated. I don't think I've seen a pistol caliber AR that uses anything but blowback.

Although, I'm willing to admit there is way more stuff out there than I've seen, so I could be wrong. In this case, I'd say my confidence is high.;)

C4IGrant
01-21-07, 12:28
9mm is 100% blow back (no gas system). I personally like the middy"look", but it is really just personal preference.

Marc, I have the RRA middy 9mm uppers in as well.



C4

AR-15A3
01-21-07, 12:32
I built my RRA A4 16" with CAR handguards last April and later on when I SBR it, shorten it to 10.5".

Someone also told me that there was another way, get the middy with the gas block model, change the handguards to a middy FF rails (or longer), when converting to a SBR just remove the gas block (it won't have any holes under the barrel like a standard FSB), shorten the barrel and use a can as an option.

If you're going to use a can, make sure the can is compatible with the FF rails you're going to use.

My 9mm carbine have all RRA components except the Hahn top load mag block, Colt mag, duckbill grip and an aftermarket buttstock.

C Products will be releasing their Colt clone 32 rounds mags by the end of this month, their version is a stainless steel with black teflon finish and same as Colt's bolt hold open followers for around $30 each.

M4arc
01-21-07, 12:56
9mm is 100% blow back (no gas system). I personally like the middy"look", but it is really just personal preference.

Marc, I have the RRA middy 9mm uppers in as well.



C4

What about RRA 9mm lowers?

C4IGrant
01-21-07, 13:04
What about RRA 9mm lowers?


Can order you one of those if you like.


C4

Nathan_Bell
01-21-07, 17:33
9mm is 100% blow back (no gas system). I personally like the middy"look", but it is really just personal preference.

Marc, I have the RRA middy 9mm uppers in as well.



C4

How does the RRA mag well adaptor attach to the lower? I have been thinking about your suggestion on feeding the beast and 9MM might be in the future, but I do NOT want to take a chance on damaging my lower.

SuicideHz
01-21-07, 18:51
what's a "gasblock half moon thing?"

Dport
01-21-07, 19:37
what's a "gasblock half moon thing?" I'm guessing the brass deflector, which for the 9mm is also supposed to deflect gases.

C4IGrant
01-21-07, 19:42
How does the RRA mag well adaptor attach to the lower? I have been thinking about your suggestion on feeding the beast and 9MM might be in the future, but I do NOT want to take a chance on damaging my lower.


You tighten a screw at the bottom that locks it into place.



C4

M4arc
01-21-07, 19:42
How does the RRA mag well adaptor attach to the lower? I have been thinking about your suggestion on feeding the beast and 9MM might be in the future, but I do NOT want to take a chance on damaging my lower.

Yeah, does the RRA 9mm lowers use an adapter? Is it forged that way or is there some sort of permanent adapter?

Nathan_Bell
01-21-07, 20:22
You tighten a screw at the bottom that locks it into place.



C4

Two questions on that. Is it possible to over tighten and break stuff? Do you still use standard mag release lever?

Resq47
01-21-07, 22:25
Yeah, does the RRA 9mm lowers use an adapter? Is it forged that way or is there some sort of permanent adapter?

Hope so, my spare 5.56 lower is a 9mm marked RRA. ;)

IOW - They're the same as 5.56 other than the marking.

mark5pt56
01-22-07, 06:27
I suggest the top loading block. "drops in" from the top, mine was really tight, they are pricey for the good ones.

I strongly suggest having the bolt ramped by Lee Minor and you need the 9mm hammer. If you don't ramp the bolt, the hammer/trigger pins take a beating and are subject to breaking, hence the suggested ss pins. The hammer "hook" will also beat the piss out the disconnector. Cure for that-ramp the bolt and grind it(hammer) down some. If I remember correctly, once the bolt is ramped, you can keep the regular hammer.

M4arc, For info, Bob Yurina did all of my work, modified th emags, cut the barrel, installed the tros 3 lug, etc.
Simply Dynamic has the upper now and is on one of his pic threads.

My true suggestion-save the money and don't do any of it. Unless you need a secret squirrel suppressed limited range sniper stick.

oh yeah--the set screw block is a piece of crap, doesn't stay, will mark the lower up. I've seen peopl edo permanent mods to the lower to keep it locked in.

C4IGrant
01-22-07, 09:09
Two questions on that. Is it possible to over tighten and break stuff? Do you still use standard mag release lever?


I guess, but you would have to be an idiot to do it. :D They use the standard mag release button.



C4

C4IGrant
01-22-07, 09:11
I suggest the top loading block. "drops in" from the top, mine was really tight, they are pricey for the good ones.

I strongly suggest having the bolt ramped by Lee Minor and you need the 9mm hammer. If you don't ramp the bolt, the hammer/trigger pins take a beating and are subject to breaking, hence the suggested ss pins. The hammer "hook" will also beat the piss out the disconnector. Cure for that-ramp the bolt and grind it(hammer) down some. If I remember correctly, once the bolt is ramped, you can keep the regular hammer.

M4arc, For info, Bob Yurina did all of my work, modified th emags, cut the barrel, installed the tros 3 lug, etc.
Simply Dynamic has the upper now and is on one of his pic threads.

My true suggestion-save the money and don't do any of it. Unless you need a secret squirrel suppressed limited range sniper stick.

oh yeah--the set screw block is a piece of crap, doesn't stay, will mark the lower up. I've seen peopl edo permanent mods to the lower to keep it locked in.

The drop in ones are nice, but on the pricey side for sure.

I run the standard Colt mag block and have NEVER had an issue with it. Did I get lucky with mine or did you get unlucky with yours?


C4

mark5pt56
01-22-07, 09:19
The drop in ones are nice, but on the pricey side for sure.

I run the standard Colt mag block and have NEVER had an issue with it. Did I get lucky with mine or did you get unlucky with yours?


C4

I think you got lucky Grant. I remember alot of people complaining about the set screw ones. One guy drilled a hole in his recvr and added a detent, actually was a good job.
I had to crank mine down and it would still loosen up. I went the top loading block and it worked great.

C4IGrant
01-22-07, 09:23
I think you got lucky Grant. I remember alot of people complaining about the set screw ones. One guy drilled a hole in his recvr and added a detent, actually was a good job.
I had to crank mine down and it would still loosen up. I went the top loading block and it worked great.


When I was on TOS, I hung out in the pistol calibers forum and really don't remember anyone complaining about them. I wonder if this is a new thing?

The top loading ones are nice (no doubt), but they are almost double the price!

It is my opinion that if you can get the standard Colt model to work then just go with that. If it doesn't then go with the top loading one.



C4

Nathan_Bell
01-22-07, 12:52
I guess, but you would have to be an idiot to do it. :D They use the standard mag release button.



C4


Hmm, I guess that means I should not try to do it before at least two cups of coffee:D

Will ponder

SuicideHz
01-22-07, 18:34
I have a NM 2-stage RRA from Steve in my Noveske lower. I am planning on SBRing it and just swapping uppers. I don't need the LCW pistol only lower my Colt RO635 came on...

I have heard that I can used the NM trigger fine with this upper, maybe because there is no traditional hammer hook on it?

Also, it seems that the pictures of "ramped" bolts I have seen have a lot of material taken away where mine doesn't have all that material. It's "ramp" is quite far back on the bolt.

Maybe I just don't know enough and it's wishful thinking.

I'll have to get some pictures up so I can get a conclusive answer.

What are '99 RO635 uppers going for? I heard at least $650 or so for the upper only, is that true?

Pep
02-09-07, 10:06
....................New to the forum, sorry for the hijack...............


(mark5pt56) , I've read your reply to a post & this caught my eye.

(I strongly suggest having the bolt ramped by Lee Minor and you need the 9mm hammer.)

I was wondering if you would have any info on Lee Minor . I was considering having my 9mm RR bolt ramped & using a DPMS hammer on my lower.
I was also going to ask if a standard 9mm hammer would work reliably w/ a ramped bolt. I thought a 9mm hammer would not be needed w/ the bolt ramped.

I like the Hahn blocks, ($$$). I was going to use the Hahn top loader for a quick change upper setup, but I guess the BHO feature is an extra i would like to have so I was left w/ spending $25 more for a dedicated Hahn top loader.

thanks & take care.

Pep.

SHIVAN
02-13-07, 10:03
I use the dedicated Hahn (http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=1548&title=AR-15+9MM+CONVERSION+BLOCK) block since I am using Colt pattern mags.

http://www.brownells.com/Images/Products/100000443a.jpg

I use a Specialized Armament ramped and tungsten weighted bolt/carrier. I also run KNS Anti-rotation pins.

My upper is a RRA 9mm with a DD M4 7.0 and a TROS 5" 3 lug barrel. I shoot it with the Trident 9 in place 100% of the time.

My upper looks like this:

http://title2.com/v-web/gallery/albums/album02/Alphasd.jpg

SuicideHz
09-29-07, 13:42
Update-

RRA 2 stage would get caught up on a lip on the bolt. I filed it off myself but had it ramped for good measure.

Runs like a champ and bumps like a sewing machine when suppressed.

The Archangel
09-29-07, 21:06
Here's another Tros 5" barrel upper with a 7" Daniel Defense FF Rail. Pictured with my AAC Phantom.

http://www.mustangmods.com/ims/u/128/7703/198236.jpg

http://www.mustangmods.com/ims/u/128/7703/198234.jpg

edlmann
10-13-07, 09:47
I think the CAR vs. Mid is only a matter of which handguard length you prefer in 9mm ARs. Unfortunately this is like the blind leading the blind so I should probably shut up until we find a definitive answer on this ;)

True. I like the look of the mid-length handguard better with a 16" barrel, but that's a matter of personal preference.

There's a couple of other benefits with the mid-length handguard and the 16" barrel:

1. The bayonet lug becomes functional; and

2. The sight radius is a bit longer.

If you plan to use an optical sight and never intend to mount a bayonet, then you're back to the looks of it.

RyanS
11-09-07, 16:44
So how are the RRA 9mm ARs? Do the issues apparent in their 223/556 rifles come into play when dealing with the 9mm?

CONKLE73
01-08-08, 11:53
It only matters as to where you want the fsb.
It is not gas operated