Now I don't especially feel like paying $50 for what is essentially a gas-through. How hard would it be to make your own Vert Adapter for the A5?

What do you mean a Vert Adapter?

Your marker has a Vertical ASA built into the Tombstone Adapter.

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"So you wanna be a agg supastar, and play hard, wit ya ProFlex, lime pods..."

The DOP vert adapter replaces the stock grip with a gas-through. It removes the idiotic placement right in front of the trigger. I don't like it anyhow; I'd like it more like the 98c, where you put your exp chamber off the end of the grip.

see: http://www.pbreview.com/products/reviews/2141/