I was thinking that one way around this would be to have gun clubs set themselves up as buyers to obtain weapons directly from manufacturers for resale (at a discount) to their members.
Then I remembered that the law requires interstate transfers he made through federally licensed gun dealers, right? Not sure a club could attain such a license. So the way all the pieces of the jigsaw puzzle fit together really falls into place: interstate transfers (and within some states all sales) require a gun dealer. So drive all the gun dealers out of business by denying them credit access.
Can't be done. Using your own hypothetical, what is stopping the gun club members from providing the capital and opening their own gun store??? It would have not only the gun club members, but the rest of the "gun buying public" as customers. Use the profits to benefit the club.