For what you describe an ACR is probably your best bet then have a barrel made in non restricted length in 300 blackout. You can buy ammo and it uses same bolt and mags as .223 so it's an easy swap and has similar ballistics to 7.62x39 but is much more versatile. 450 will be a long wait and 50 beowulf is just too expensive to be practical until the manufacturers catch up on mags and ammo.
If your inerested Ian at Herron Arms can make a barrel for you and I found a guy in Southern Alberta who can do it as well. Both will have it reclassified to non restricted once the longer barrel is installed.
If your inerested Ian at Herron Arms can make a barrel for you and I found a guy in Southern Alberta who can do it as well. Both will have it reclassified to non restricted once the longer barrel is installed.
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