Arizona_Mike
Member
- Joined
- Feb 15, 2013
- Messages
- 3,452
I am starting a new thread because things have changed so much. Here was the old thread: www.thehighroad.org/showthread.php?t=747086
My 9mm AR15 experience has been quite a misadventure to this point. I struggled to get the trigger disconnector of my match grade trigger to work with the 9mm ramped bolt and finally had to relocate the takedown pin hole upward to resolve that problem. Why would I do such a thing, you ask? Well, because I have one lower with all the bells and whistles and more importantly an SBR tax stamp. I still have a bit of tuning to do (I can provoke the problem on occasion by firing the gun upside down) but it is essentially solved for a range toy). Besides, when the disconnector fails it fails in the boring way and not the exciting way.
My other problem was FTFs with the rounds overshooting the chamber as in the first picture below. Speaking with Hahn Precision they blamed the C-Products mags and suggested Metalforms. My Metalforms arrived in Saturday's mail and I dry cycled about 500 rounds through them and have the following observations:
1. I have zero instances of the round overshooting the chamber. That was my big problem with the C-Products mags (as shown in the photo below) and it is totally gone with the Metalforms. The lips of the Metalforms sit about 45 thousandths lower in the gun than the C-Products mags which makes me want to try to modify one of my 6 C-Products mags by enlarging the catch hole.
2. With "dry" Metalform mags I got a lot of slow-magazine type FTFs most occurring in the mouth of the mag and occasionally partially in the mag and against the front of the feed ramp. They are nothing like the "bad geometry" fails I got with the C-Product mags but the classic case of the boltface catching the round mid body or on the extractor groove instead of the rear. The metal on metal friction of the metal follower and metal mag body is pretty rough. When dusting with motor mica failed to help, I switched to very lightly lubricating the inside of the magazine bodies with LP. I basically removed all of it except what impregnated in the surface by running a swab of paper towel through after lightly coating. I know you are not "supposed" to lubricate magazines (attract dust and all that) and perhaps I can try graphite or another product. BUT IT WORKED. The follower moves smoothly now and the slow mag FTFs are gone.
3. I have one last FTF issue that happens when the follower fails to rise after the 5th to the last round has been ejected and the last 4 rounds are in the mag. This is rounds 17-20 in a 20rd mag and 29-32 in a 32 rd mag. The last round gets hung up between the follower and the bottom of the vertical ribs near the top of the mag and the other 3 rounds are loose (you can invert the mag and pour them out).
I've dropped my phone a few time too many times and the camera no longer focuses well. The last 4 rounds failing to rise (you can see more clearly in the shadow that they are loose and not raising to the feed lips):
After pouring out the three loose rounds you can see the last round jammed between the follower and the bottom the of vertical ribs on the right side of the mag body:
Mike
My 9mm AR15 experience has been quite a misadventure to this point. I struggled to get the trigger disconnector of my match grade trigger to work with the 9mm ramped bolt and finally had to relocate the takedown pin hole upward to resolve that problem. Why would I do such a thing, you ask? Well, because I have one lower with all the bells and whistles and more importantly an SBR tax stamp. I still have a bit of tuning to do (I can provoke the problem on occasion by firing the gun upside down) but it is essentially solved for a range toy). Besides, when the disconnector fails it fails in the boring way and not the exciting way.
My other problem was FTFs with the rounds overshooting the chamber as in the first picture below. Speaking with Hahn Precision they blamed the C-Products mags and suggested Metalforms. My Metalforms arrived in Saturday's mail and I dry cycled about 500 rounds through them and have the following observations:
1. I have zero instances of the round overshooting the chamber. That was my big problem with the C-Products mags (as shown in the photo below) and it is totally gone with the Metalforms. The lips of the Metalforms sit about 45 thousandths lower in the gun than the C-Products mags which makes me want to try to modify one of my 6 C-Products mags by enlarging the catch hole.
2. With "dry" Metalform mags I got a lot of slow-magazine type FTFs most occurring in the mouth of the mag and occasionally partially in the mag and against the front of the feed ramp. They are nothing like the "bad geometry" fails I got with the C-Product mags but the classic case of the boltface catching the round mid body or on the extractor groove instead of the rear. The metal on metal friction of the metal follower and metal mag body is pretty rough. When dusting with motor mica failed to help, I switched to very lightly lubricating the inside of the magazine bodies with LP. I basically removed all of it except what impregnated in the surface by running a swab of paper towel through after lightly coating. I know you are not "supposed" to lubricate magazines (attract dust and all that) and perhaps I can try graphite or another product. BUT IT WORKED. The follower moves smoothly now and the slow mag FTFs are gone.
3. I have one last FTF issue that happens when the follower fails to rise after the 5th to the last round has been ejected and the last 4 rounds are in the mag. This is rounds 17-20 in a 20rd mag and 29-32 in a 32 rd mag. The last round gets hung up between the follower and the bottom of the vertical ribs near the top of the mag and the other 3 rounds are loose (you can invert the mag and pour them out).
I've dropped my phone a few time too many times and the camera no longer focuses well. The last 4 rounds failing to rise (you can see more clearly in the shadow that they are loose and not raising to the feed lips):
After pouring out the three loose rounds you can see the last round jammed between the follower and the bottom the of vertical ribs on the right side of the mag body:
Mike
Last edited:
