This is going to sound heretical but......
I wish the M20 was a tad heavier. A 5lb rifle in 284 or 308 might be a tad sporty. I've never shot one but have heard from more than 1 owner the perceived recoil is less than it would seem. I've been toying with building/buying another 0.284 cartridge and the 284 win always seemed like a good choice. A 139 LRX in a 284 win would likely cover alot of ground
What is the mag box COAL on the M20? If I recall it's close to 3"?
I've been hunting with a NULA .308 for at least twelve years. It has a #1 22" barrel and it weighs just under 6 lbs. with a 6x36 Leupold. Recoil is noticeably less than I anticipated, even with 180 grain bullets and its not uncomfortable to shoot even off the bench. Whether it's stock design or something else, I don't know, but recoil is quite manageable. I can say the same for a NULA 28 in 7x61 Sharpe & Hart, but I had Mr. Forbes put a 26" #3 barrel on that one as I anticipated a heavy recoil. Recoil is not at all unpleasant. It weighs just under seven pounds with a 2.5x-8x Leupold.
I haven't measured the magazine box on the .308 in quite a while, but I know it can handle a longer OAL than other .308 magazines. It may be 3". I no longer do any load development with this rifle; I've settled on a Barnes 150 TTSX and H4895 powder. Works well on elk. OAL is conventional .308 at 2.81".
