The bolt hold open actuator fits between the lower and upper receiver. It interfaces and allows full operation of the bolt catch. Without it, the green follower of your magazine locks back the bolt - until you remove the mag, then it closes thus requiring you to manually use the bolt catch when pulling back the bolt. When you get the evo mag, you should purchase the BHOA, it's only $20 over here and is designed to work with the evo mags. The only other mod you may need to do with the BHOA is cut a coil or two off the bolt catch spring, I did, and I gain complete functionality when I use my conversion bolt.
Webley Vulcan .22, Webley Tempest .177, Beeman Kodiak .25, Beeman R9 .177, Weihrauch HW30 .177, Slavia 618 .177, Colt Commander .45ACP, Browning Hi-Power 9mm, Bushmaster AR-15 5.56/.223
Webley Vulcan .22, Webley Tempest .177, Beeman Kodiak .25, Beeman R9 .177, Weihrauch HW30 .177, Slavia 618 .177, Colt Commander .45ACP, Browning Hi-Power 9mm, Bushmaster AR-15 5.56/.223
On the subject of magazines Black Dog has a new magazine out called the X form.
Black dogs will not operate the BHOA.
Webley Vulcan .22, Webley Tempest .177, Beeman Kodiak .25, Beeman R9 .177, Weihrauch HW30 .177, Slavia 618 .177, Colt Commander .45ACP, Browning Hi-Power 9mm, Bushmaster AR-15 5.56/.223
Lantac / CMMG will have a pay & play range at Shield Shooting Centre Dorset 7th & 8th of July , so come on down have a go & raise some money for a worth while cause. £3 a go.
Full info along with match entry over at http://four4islands.org
Just though i'd do a little update after nearly a year of using the CMMG in anger....
well I'm still happy with it, it's still knocking over bunnies, The only thing i've found is the BOHA can be a little temperamental unless the mags are operating smoothly and the BOHA is spotlessly clean. I got a couple of 10 round mags recently and it makes the whole shooting from the vehicle exercise a lot easier due to not having 4" of the mag catching on the door, all in all still well impressed with it, I've only have a couple of jams but I am using subs so I expected a lot more until the thing has had a few 1000 rounds through it.
CMMG have stopped making the BHOA and the last 2 generations of magazine, they've gone back to the first gen grey mag that works like a blackdog.
Ten round mags are definitely the way forward for hunting, especially from a vehicle. If they are BDM ten round mags you can open them up and remove the stop pin inside to extend the capacity to 15 rounds.
I have a Better-Mag adapter in my CMMG, using 10 round M&P mags is easy enough and they're pretty cheap from Brownells these days.