After inserting and removing the adapter a dozen or two times, I
found that the latch started engaging the adapter and securing it in position.
At the same time, the aluminum adapter seemed to be self clearencing a
small bit where we milled away that .010". This was enough to improve the length dimension
that we had been having issues with.
My adapter, when it arrived, was missing a piece or two for the
ambidextrous release. You can see the hole for it next to the magazine
latch. During final assembly, it was discovered that one of the pieces had
been machined to the wrong dimension. Rather than delaying the adapter,
MSA shipped it and promised to follow up with the new piece and a couple of roll
pins for assembly once they had the correct pieces in hand.
Here is a view of a Magpul magazine fully inserted into the adapter.
The bolt is held open with the Saiga's bolt hold open catch. In this
position, it has already contacted the base of the .223 cartridge and
began to strip the round out of the magazine and into the chamber.
Viewed from a different angle, you can see the same .223 cartridge nicely aligned at the chamber opening. As I write this, I've not yet been to the range but this is certainly what you want to see at this point. I've cycled .223 dummy rounds (no primer or powder) through the Saiga and they have reliably fed from several different AR-15 magazines. MSA got the positioning of the AR-15 magazine within the adapter right on the money from what I can tell.
We originally started out with an end mill bit and the cuts
looked very clean. We then had to swap over to a ball mill bit as the
end mill we were using was a little too short and we couldn't cut deep
enough. The cuts didn't look clean with the ball mill....I didn't like
the radius type cuts. It looked more like we went at it with a Dremel
We all know the AK pattern rifles were built on loose
tolerances (hence they will run under most any condition). It is quite
possible that some of our problems resulted from slightly different
dimensions than those used during R&D by MSA. I put enough aftermarket
parts on a Jeep to realize that not all Jeeps, regardless of them being the
same model, are not dimensionally exact. I've not doubt that Russian
made rifles can suffer the same.
You do NOT need anywhere close to .94" depth. It will
simply remove more material than is necessary. Note: Stay
with the .88" to .89" depth number.
While the milling didn't turn out as clean as I wanted it, I
would have been less happy attempting it with a Dremel tool. The
Russian metal certainly isn't any too soft in the Saiga rifle.
I know I can wrench a Jeep TJ better than I can gunsmith. I'll admit that I've got a few more hours doing the former.
Since the factory Saiga magazine still fits (I'll function test it too at the range), I'll keep it for shooting off the bench since it's 10 shot profile lends itself to that task. I had read a comment from a beta tester that said the AR-15 magazines drop clean when released from the adapter. Mine do not. I've tried Colt, Brownell, Midway Stoner, and Magpul and they all require manual extraction once the release is depressed. This may be an issue for some folks and it may not be for others. Once I get the parts for the ambidextrous release installed, I am hoping I can release the magazine with my right hand (with hand remaining on the pistol grip) and extract it with my support hand. For what it is worth, not all of my AR-15 magazines drop clean from my Eagle Arms EA-15 rifle either.
I look forward to a trip to the range where I can try out the new adapter. I'll provide an update on this page once I get that taken care of and let you know how it performs under fire.
MSA added some comments to the forum thread regarding the mags dropping free from the adapter. I've added their info here:
With respect to the AR mags, I have found a few to range in tolerance which may or may not affect dropping freely. In my RRA AR15 I two have mags that do not always drop free from the beginning and they need to "wear in".
Another issue that comes to mind is the surface buildup from the anodize process, in this process it does affect the internal and external tolerances and can contribute to this issue.
PMags on their own are wider than most mags and do need
to wear in to properly drop as well.
A easy solution in all cases would be to take a small file to the inside of the adapter where the "Wear" marks are visible and to lightly remove away material till drop free results are achieved. Thanks again for the write up.
Thanks to MSA for sharing this additional information for
getting the most from the adapter.
More AR-15 Mag Adapter
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