9mm Ar build ? and Suggestions ?
- Thread starter bushwacker's
- Start date
Hi friends so basically what Irunguns sold me is a colt model 6450 LE 9mm SMG - the lower my son and I recently inherited 2 lowers 1 complete the other stripped so this upper Kit came with the Mag block that gets inserted into the magazine well and pinned on the 6450 my next question is do I have to install a 9mm Hammer in the lower ?
I was just watching a video where the guy breaks down the 6450 and he did point out the 9mm hammer , I honestly thought I could use the 9mm upper on my .556 lower that was part of the attraction I am starting to think I should have just purchased a complete 9mm pistol there is a complete pistol on the site for less than I paid for the upper kit .
I have to admit that I personally like the classic AR-9 SMG configuration A2 that is why I did not go for the flat top I have a feeling this unit will be as much fun as a guy can have with 5 rounds haha well anyway friends tell me I need a 9mm hammer and have to pin that Mag block to the lower ?
I think I know the answer thanks for all your help
Bushy
I was just watching a video where the guy breaks down the 6450 and he did point out the 9mm hammer , I honestly thought I could use the 9mm upper on my .556 lower that was part of the attraction I am starting to think I should have just purchased a complete 9mm pistol there is a complete pistol on the site for less than I paid for the upper kit .
I have to admit that I personally like the classic AR-9 SMG configuration A2 that is why I did not go for the flat top I have a feeling this unit will be as much fun as a guy can have with 5 rounds haha well anyway friends tell me I need a 9mm hammer and have to pin that Mag block to the lower ?
I think I know the answer thanks for all your help
Bushy
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Ok so I just found a answer to my question on Ar15.com "Sometimes. You can avoid the problem by just buying the right type of hammer in the first place. DPMS parts kits come with a "smooth faced" hammer. "
The classic M16 a1 hammer will work ok also , but the buffer is still going to be too heavy to switch over too .556 but thats not too bad live and learn .
Maybe this can become the 9mm build thread
Bushy
The classic M16 a1 hammer will work ok also , but the buffer is still going to be too heavy to switch over too .556 but thats not too bad live and learn .
Maybe this can become the 9mm build thread
Bushy
When I was looking for a 9mm AR I priced out all the parts to build and looked into availability and decided to buy a complete rifle. I found a Bushmaster carbon 15 in 9mm that the owner had broken the upper receiver. I got a good price for all his parts and magazines and just swapped in an aluminum flat top upper. The rifle has been running like a top since.
Building a 9mm AR from the ground up is expensive and not many retailers carry the parts.
Magazine selection is a personal choice, I would have gone with glock mag lower just because glock mags are all 10 round legal and they can be found most places. I ended up with Colt mag pattern and while I thought they would be hard to find it turns out they're not that bad and I have 5 pistol mags and 3 pinned 5/32 mags now.
The 9mm AR is a lot of fun and everyone who shoots it likes it. There is virtually no recoil so anyone can shoot it comfortably. I've let my 8 year old nephew shoot mine and the smile on his face lasted for hours.
It's also surprisingly accurate at under 100 yards.
Building a 9mm AR from the ground up is expensive and not many retailers carry the parts.
Magazine selection is a personal choice, I would have gone with glock mag lower just because glock mags are all 10 round legal and they can be found most places. I ended up with Colt mag pattern and while I thought they would be hard to find it turns out they're not that bad and I have 5 pistol mags and 3 pinned 5/32 mags now.
The 9mm AR is a lot of fun and everyone who shoots it likes it. There is virtually no recoil so anyone can shoot it comfortably. I've let my 8 year old nephew shoot mine and the smile on his face lasted for hours.
It's also surprisingly accurate at under 100 yards.
I run my 9mm on a standard 556 hammer and it works fine. Most of the issue can be solved with a ramped bolt. If yours isn't, it is fairly easy to do. Basically it just softens the hit the hammer receives from the BCG.
No doubt ArfCom will disagree but I did a bunch of testing with different buffer weights and it takes a hell of a lot of weight to disrupt the firing sequence of a 556 rifle. You will be fine using a 9mm buffer with a 556 upper.
So I got out to the range and ran about 400 rounds through it, about half half 124gr and 147gr
At first I ran the 9mm hydraulic buffer with JP .308 spring. The rifle shot very smooth with that setup but for some reason the hammer would not reset after every shot. I would have to manually charge it again, ejecting an un fired round and then it would reset and shoot again.
So I swapped out to a regular H3 buffer, and then it cycled fine, no more malfunctions, but the recoil and blowback was much harsher then it was with the hydraulic buffer.
Im going to contact the manufacturer and ask them if they have any suggestions why the 9mm buffer is not resetting the trigger, hopefully I can get it to work because it shoots super smooth with that buffer, just wont reset the hammer right now for whatever reason...
Also loving the new Trijicon MRO optic!
And here is a picture of the 9mm AR I almost bought off a range officer, before I decided to build my own instead. Its using the colt mags and its still for sale in the show room
At first I ran the 9mm hydraulic buffer with JP .308 spring. The rifle shot very smooth with that setup but for some reason the hammer would not reset after every shot. I would have to manually charge it again, ejecting an un fired round and then it would reset and shoot again.
So I swapped out to a regular H3 buffer, and then it cycled fine, no more malfunctions, but the recoil and blowback was much harsher then it was with the hydraulic buffer.
Im going to contact the manufacturer and ask them if they have any suggestions why the 9mm buffer is not resetting the trigger, hopefully I can get it to work because it shoots super smooth with that buffer, just wont reset the hammer right now for whatever reason...
Also loving the new Trijicon MRO optic!
And here is a picture of the 9mm AR I almost bought off a range officer, before I decided to build my own instead. Its using the colt mags and its still for sale in the show room
Personally I paid extra for a GLOCK mag lower, since I already own 10+ Glock 17 and 19 mags for my pistols, its just makes more sense for me to go with a Glock mag fed lower...Now If I owned an UZI.....
