I find it odd in the extreme that it's so "difficult" to make a bolt action rifle feed easily from a double stack-double feed detachable magazine when virtually all of them were designed to feed from a double stack-double feed internal magazine.
Can someone shed some light on that?
I believe you are incorrect.
Only a handful of R700 style receivers were designed to feed from a DS/DF mag. Those were the terrible 700DMs.
They were a half assed afterthought in design and sucked big time. F'ing terrible.
R700 style receivers are designed to feed from a
double stack internal box but the actual feed lips are integrally machined into the bottom of the receiver. The mag box just pushes the rounds up and into the receiver's integral feed lips.
Those integral feed rails are fixed and very close to the bolt path of the receiver.
They are a totally different geometry than the AW mag feed lips and retain the rounds in a totally different manner.
They occupy a different point in space relative to the bolt path compared to the AW mag feed lips.
Win 70, Mausers, etc.. all used the same concept of integral feed lips on the receiver and a separate floating mag box below it.
The AW mag feed lips are also formed to allow the larger bolt body (larger than R700) of the Acc Intl to cycle between the edges of the lips.
The AW mag and its feed lips were never meant to run with a 2 lug bolt.
They (Acc Intl) were only interested in the bottom lug of their own front 3 lugs stripping rounds out of the magazine (which it does very well). That 6 o'clock lug digs deep into the mag plus the bolt nose face is nice and flat from the edge of the lug to the drop into the breech face.
In R700 style actions, the host DBM that positions an AW magazine has to be perfectly setup in the Z-axis to place the AW's feed lips as close to the bolt path as possible. Even then, it has zero room for error and doesn't tolerate rounds getting out of position.
So..... you are trying to make a double stack mag designed for a different action work in actions it was never meant to be around.
I ship a lot of SENTINEL spec guns with AW mags and they run "pretty good".
I would never ship a 2-lug work gun to an agency with AW mags.
I am not an expert on the Acc Intl products but those are just a few things I know from dealing with the AW vs. AICS mags. SMEs like Tooley, etc will prolly have lots better info and could relay it better than me.
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