My 9mm sbr I just finished this week.

redtazdog · Post by **redtazdog** » Sat Sep 13, 2008 5:47 pm

Mr8shot wrote:I'm actually pretty sure it's my mag well thats causing all my problems.

Do the mags have the newest followers

redtazdog · Post by **redtazdog** » Sat Sep 13, 2008 5:51 pm

rob_s wrote:Got mine!

Nice

rob_s · Post by **rob_s** » Sat Sep 13, 2008 5:57 pm

Mr8shot wrote:I'm actually pretty sure it's my mag well thats causing all my problems.

You know what your first clue should be? If it says "Cproducts" on the bottom, chances are it's the complete POS mags.

I have a bunch, and I'm not holding my breath that they're going to work in the new SBR.

Mr8shot · Post by **Mr8shot** » Sat Sep 13, 2008 6:05 pm

well somehow the bolt is hitting the top of the mags causing the rifle to jam. So either the mags are crap or the adapter is loose causing the mag to move.

Mr8shot · Post by **Mr8shot** » Sat Sep 13, 2008 6:06 pm

redtazdog wrote:
Mr8shot wrote:I'm actually pretty sure it's my mag well thats causing all my problems.
Do the mags have the newest followers

All miner are marked 9mm

redtazdog · Post by **redtazdog** » Sat Sep 13, 2008 6:20 pm

rob_s wrote:
Mr8shot wrote:I'm actually pretty sure it's my mag well thats causing all my problems.
You know what your first clue should be? If it says "Cproducts" on the bottom, chances are it's the complete POS mags.

I have a bunch, and I'm not holding my breath that they're going to work in the new SBR.

I have 10 CP mags and they all work great if your lower and upper are mill spec.
I have noticed that some lowers to upper fit if not in spec may bring the mag closer to the bolt and will cause the mag lip drag.
There is small mag fitting mods that will fix this problem if needed.

rob_s · Post by **rob_s** » Sat Sep 13, 2008 6:30 pm

Mr8shot wrote:well somehow the bolt is hitting the top of the mags causing the rifle to jam. So either the mags are crap or the adapter is loose causing the mag to move.

I can see in mine that the same thing is going to happen. You can lower the block by loosening the allen screw at the front inside the magwell.

And CP mags are still garbage made by horrible company.

rob_s · Post by **rob_s** » Sat Sep 13, 2008 6:31 pm

redtazdog wrote:
rob_s wrote:
Mr8shot wrote:I'm actually pretty sure it's my mag well thats causing all my problems.
You know what your first clue should be? If it says "Cproducts" on the bottom, chances are it's the complete POS mags.

I have a bunch, and I'm not holding my breath that they're going to work in the new SBR.
I have 10 CP mags and they all work great if your lower and upper are mill spec.
I have noticed that some lowers to upper fit if not in spec may bring the mag closer to the bolt and will cause the mag lip drag.
There is small mag fitting mods that will fix this problem if needed.

What exactly is the "mil spec" for a 9mm AR? What does that even mean?

redtazdog · Post by **redtazdog** » Sat Sep 13, 2008 6:35 pm

Mr8shot wrote:well somehow the bolt is hitting the top of the mags causing the rifle to jam. So either the mags are crap or the adapter is loose causing the mag to move.

Your mags are sitting to high because of the mag notch cut, or your lower is machined off spec or the upper is machined off spec.
Contact Cproducts- Larry has been more than helpful. I love the fact that with one phone call he will make it right-no questions.
I have 1 lower out of 16 at home that will bring the mag and bolt close enough to rub.

Mr8shot · Post by **Mr8shot** » Sat Sep 13, 2008 6:39 pm

rob_s wrote:
Mr8shot wrote:well somehow the bolt is hitting the top of the mags causing the rifle to jam. So either the mags are crap or the adapter is loose causing the mag to move.
I can see in mine that the same thing is going to happen. You can lower the block by loosening the allen screw at the front inside the magwell.

And CP mags are still garbage made by horrible company.

My block in non adjustable

Mr8shot · Post by **Mr8shot** » Sat Sep 13, 2008 6:42 pm

I will call larry monday.

redtazdog · Post by **redtazdog** » Sat Sep 13, 2008 6:48 pm

rob_s wrote:
redtazdog wrote:
rob_s wrote: You know what your first clue should be? If it says "Cproducts" on the bottom, chances are it's the complete POS mags.

I have a bunch, and I'm not holding my breath that they're going to work in the new SBR.
I have 10 CP mags and they all work great if your lower and upper are mill spec.
I have noticed that some lowers to upper fit if not in spec may bring the mag closer to the bolt and will cause the mag lip drag.
There is small mag fitting mods that will fix this problem if needed.
What exactly is the "mil spec" for a 9mm AR? What does that even mean?

I dont think there is a mill spec for just 9mm.
Excuse me

In spec machine work on any upper or lower is the same when it comes to the fit and function, but some maker are sometimes off a little.

If the machine work is off on the lower or the upper things dont work the way you like.

Mr8shot · Post by **Mr8shot** » Sat Sep 13, 2008 6:57 pm

All I know is that I'm getting really fustrated with this gun and also the fact that I'm blowing thru all my ammo to get it to work.

If I get new mags and they work I'll be happy if they don't work then I just don't know....

redtazdog · Post by **redtazdog** » Sat Sep 13, 2008 7:00 pm

rob_s wrote:
Mr8shot wrote:well somehow the bolt is hitting the top of the mags causing the rifle to jam. So either the mags are crap or the adapter is loose causing the mag to move.
I can see in mine that the same thing is going to happen. You can lower the block by loosening the allen screw at the front inside the magwell.

And CP mags are still garbage made by horrible company.

I think CP is making the mags for Colt now

I was luck enough to have 10 real Colt mags that I purchased 15 years ago for cheap.
You can find Colt mags aound for 50 to 60 bucks or go with CP for 1/2
the price.
I have seen Colt mags give hell to 9mm makes of many too,
Remember the 9mm colt was the after thought of the 223.

chrismartin · Post by **chrismartin** » Sat Sep 13, 2008 7:27 pm

Mr8Shot,

Check your ejector alignment too. The default Hahn ejector is straight. You may need to bend it into the center to properly eject the rounds. This problem will appear to be a stovepipe or double feed type problem.

You want the ejector to be as close to the center of the bolt as possible, even riding the bolt slightly (the ejector has a little wiggle, so it will move out of the way a little.)

I had to bend mine up and into the center to get good ejection. Ever since I did this I have had reliable operation. I was experiencing a ton of feeding issues that looked like bolt-over-round (5.56 speak would be over-gassed) type problems. I thought they were magazine related, but were really ejection problems that were causing the feeding issue.

I even tried taking a few thousandths off the top magazine catch to lower the magazines. Doesn't take much to lower the mag enough to get it off the bolt.

tgbrowning · Post by **tgbrowning** » Sat Sep 13, 2008 7:29 pm

For What it's Worth. We sell a lot of 9mm upper receivers where I work. The only magazines we sell are the UZI magazines modified by Rock River Arms for use in AR-15 lowers. They only hold 25 rounds, but they always work. We quit selling C-Products 9mm magazines because we had so many problems with them. My 2¢.

T.

chrismartin · Post by **chrismartin** » Sat Sep 13, 2008 7:35 pm

One more thing that I forgot. When I was getting feeding problems, I also radius the bottom of the bolt face. My Garrison bolt was sharp and the rounds looked like they were hanging up on the flat part as the round was sliding up and into the chamber. This was giving me a 3-point-jam (bolt face, bottom of chamber, nose of round into top of chamber)

I polished the bolt face and broke the corner off the bottom of the bolt where the rounds get picked up.

So, in closing, I got my 9mm AR to run by:

1. Radius and polish the bottom of the bolt where the round gets picked up, inside edges where the round slides up and into the face.
2. Adjusted the ejector to the center of the bolt.

#1 fixed the 3-point jams where the round was picked up, bottom of the round on the bolt, round did not fully chamber as the round could not slide up and into the bolt face.

#2 fixed stovepipe jams and bolt-over-round failure to feeds

The magazine catch thing in my previous post (to lower the magazine) was tried/tested to try to fix FTF's that #2 fixed, but I really didn't have a problem with the magazines sitting high.

For what it's worth, I'm only running CP 9mm mags and 1 promag. All CP's now work (gen 2 followers, and gen 1 all worked for me, though I did have to file the front down so it would not hang up on the hahn feed ramp, preventing bolt hold open from functioning. Once adjusted, BHO works fine)

Mr8shot · Post by **Mr8shot** » Sat Sep 13, 2008 7:37 pm

Thanks chris martin! I will try the ejector fix

chrismartin · Post by **chrismartin** » Sat Sep 13, 2008 8:10 pm

Here is a picture of my ejector:

Top view, you can see that I bent it towards the center of the mag well. I tried to keep it even, bending it at the base, rather than just the tip. I wanted the force from the round to push straight back on the ejector rather than forcing the ejector at an angle. I did have to bend it up as well.

Mr8shot · Post by **Mr8shot** » Mon Sep 15, 2008 8:28 pm

I tweaked my extractor and got it work with only one FTE in 100 rounds. However 3 of my X marked c-products still don't work very well. However the other 2 that are not marked X worked great.

chrismartin · Post by **chrismartin** » Mon Sep 15, 2008 8:32 pm

Mr8shot wrote:I tweaked my extractor and got it work with only one FTE in 100 rounds. However 3 of my X marked c-products still don't work very well. However the other 2 that are not marked X worked great.

TOS 9mm mag fix:

http://www.ar15.com/forums/topic.html?b=3&f=15&t=387562

Not my image, from the above link...

AR15.com USER JONBLACK wrote: Be sure the gun is safe. IE: unloaded and clear.

Lock the bolt back, stick a mag in, and then slowly hand cycle. You should see where the bolt starts to "drag" across the feed lip closest to the ejection port. File a little at a time, and retest.

Take a look at the pic for reference.

jonblack

redtazdog · Post by **redtazdog** » Mon Sep 15, 2008 9:49 pm

chrismartin wrote:
Mr8shot wrote:I tweaked my extractor and got it work with only one FTE in 100 rounds. However 3 of my X marked c-products still don't work very well. However the other 2 that are not marked X worked great.
TOS 9mm mag fix:

http://www.ar15.com/forums/topic.html?b=3&f=15&t=387562

Not my image, from the above link...

AR15.com USER JONBLACK wrote: Be sure the gun is safe. IE: unloaded and clear.

Lock the bolt back, stick a mag in, and then slowly hand cycle. You should see where the bolt starts to "drag" across the feed lip closest to the ejection port. File a little at a time, and retest.

Take a look at the pic for reference.

jonblack

This is the fix I avoided by using a diferent lower that fit better.
The lower that was machined out of spec held the block to high with the mag catch

this was a older DPMS.
The lip grind is one of the fixes that Larry at CProd would do.

Wahoo95 · Post by **Wahoo95** » Mon Sep 15, 2008 10:05 pm

This is all great info.............you're the man Chris! I'll make sure to bring mine to you if it starts acting up

Poacher · Post by **Poacher** » Mon Sep 15, 2008 10:27 pm

Chris is the man on 9mm AR fixes. I have watched him stay with alot of 9mm AR threads, always being helpful in solving problems.

chrismartin · Post by **chrismartin** » Mon Sep 15, 2008 10:43 pm

Poacher wrote:Chris is the man on 9mm AR fixes. I have watched him stay with alot of 9mm AR threads, always being helpful in solving problems.

Thanks! I'm just tryin' to help.

9mm AR story...

I built my 9mm AR for a bowling pin shoot, to compete the the carbine class and so I could use my Evo9. My local range doesn't allow rifles on the indoor and the outdoor is 25 yards+ only. I had only ever laser bore-sighted the rifle before shooting it in competition, luckily it's only 25 feet, so it's not too big of a deal.

It ran great the first time out, several times after that, I was not so lucky. That's when I started fixing all the things above. While I was having jamming issues, I was shooting it in a bowling pin shoot. I had a round jump the bolt and wedge itself between the top of the bolt and the charging handle.

Of course, this was during the competition, so I rip back on the charging handle to clear the round (not knowing where it was) and proceed to bend the gas key area of the CH so bad it cracked, locking up the gun.
it took a while, and strategic use of the craftsman 12oz tactical hammer, to get the thing apart.

I've worked things out for the most part. I only had 1 FTF during the last pin shoot a few months ago and Wahoo95 ran a bunch of ammo through it without any problems a few weeks ago.

When Wahoo95 shot it last, we even used his upper and a few mags to test some things out a little.