We went to the range last weekend to see why 12 of my FAL mags (all from DSArms) work just fine in my Argie FAL while 8 did not (and all but one or two of the bad ones work in TimW's AzEx FAL.)
So, at the range we swapped parts. His bolt in my receiver (headspace was okay), his upper on my lower (or was it vice versa).
Nothing seemed to indicate a pattern. Then we decided to see how the magazine seated in the mag well. I noticed that nearly all of the bad mags seated poorly in my FAL but not quite so poorly in the Imbel-receivered AzEx. We found that while the front of the mag was flush against the receiver, at the rear of the mag there was a distinct gap (perhaps 3 mm or so). As well, the mag in the Argie wobbled fore to aft more than in the AzEx.
We deduced that the bad mags in my Argie were actually not so great in the AzEx either. The difference was that the greater-wobbling mags in my Argie made the situation worse.
That is, the gap from the mag (caused by what appeared to be an unrepairable bending down toward the rear of the mag) coupled with the extra wobble in the Argie, allowed the round (always in the left side of the mag) to be low enough so that the bolt would barely get a bite on the rear of the cartridge.
To test this, we removed the dust cover and installed the bolt. We put a few rounds in the magazine, installed it, and tapped the bolt carrier forward millimeter by millimeter as sort of a stop-action.
We repeatedly saw the bolt either completely miss the round and slide over, or the round would be pushed halfway and then have the bolt slide over.
What could be different between the Argie and the AzEx? We guessed that the mag catch was the problem.
We took out the mag catches in both rifles and measured all the pertainant distances. Tim's mag catch measured 0.625" from the pin hole to the catch surface. My mag catch was visibly shorter, 0.039" shorter.
So, my shorter mag release caused the borderline magazines to drop even lower.
The test would be to swap one of Tim's AzEx mag catches (Tim had installed an ambi release).
I did so tonite and found that the mags did, in fact seat tighter. And two mags that were labeled as bad, now functioned (using the stop action method described above, we will go shooting tomorrow).
The problem is that I now have ten mags that work, and ten mags that don't allow the mag catch to snap them in place (as if the catch is too long for my rifle or the mags are somehow out of spec. I measured the now-tight mags to see if I could figure out if the mags needed to be filed or the catch needed to be filed. The jury is out, so far.
I will still be returning the mags (to DSA) which have the bend toward the rear. But I think I am close to getting this thing figured out.
So, which is it? How do I figure out which needs to be filed, the mags or the catch?
Rick
So, at the range we swapped parts. His bolt in my receiver (headspace was okay), his upper on my lower (or was it vice versa).
Nothing seemed to indicate a pattern. Then we decided to see how the magazine seated in the mag well. I noticed that nearly all of the bad mags seated poorly in my FAL but not quite so poorly in the Imbel-receivered AzEx. We found that while the front of the mag was flush against the receiver, at the rear of the mag there was a distinct gap (perhaps 3 mm or so). As well, the mag in the Argie wobbled fore to aft more than in the AzEx.
We deduced that the bad mags in my Argie were actually not so great in the AzEx either. The difference was that the greater-wobbling mags in my Argie made the situation worse.
That is, the gap from the mag (caused by what appeared to be an unrepairable bending down toward the rear of the mag) coupled with the extra wobble in the Argie, allowed the round (always in the left side of the mag) to be low enough so that the bolt would barely get a bite on the rear of the cartridge.
To test this, we removed the dust cover and installed the bolt. We put a few rounds in the magazine, installed it, and tapped the bolt carrier forward millimeter by millimeter as sort of a stop-action.
We repeatedly saw the bolt either completely miss the round and slide over, or the round would be pushed halfway and then have the bolt slide over.
What could be different between the Argie and the AzEx? We guessed that the mag catch was the problem.
We took out the mag catches in both rifles and measured all the pertainant distances. Tim's mag catch measured 0.625" from the pin hole to the catch surface. My mag catch was visibly shorter, 0.039" shorter.
So, my shorter mag release caused the borderline magazines to drop even lower.
The test would be to swap one of Tim's AzEx mag catches (Tim had installed an ambi release).
I did so tonite and found that the mags did, in fact seat tighter. And two mags that were labeled as bad, now functioned (using the stop action method described above, we will go shooting tomorrow).
The problem is that I now have ten mags that work, and ten mags that don't allow the mag catch to snap them in place (as if the catch is too long for my rifle or the mags are somehow out of spec. I measured the now-tight mags to see if I could figure out if the mags needed to be filed or the catch needed to be filed. The jury is out, so far.
I will still be returning the mags (to DSA) which have the bend toward the rear. But I think I am close to getting this thing figured out.
So, which is it? How do I figure out which needs to be filed, the mags or the catch?
Rick