300BO pistol mags...

I'm planning on a 300HAM'R project actually and from the info I can glean from stateside 300BO mags are pretty much a requirement.
I'll certainly give the 5.56 mags a go first
 
I'd be curious to know what the differences are between a 5.56 AR mag and a blackout mag. The blackout was designed specifically to use everything 5.56 from the get-go.
I've got a blackout, but never played with a HAM'R, so hopefully someone else can chime in.
 
The follower is slightly different in .300Blk specific mags. I haven't had any feeding issues using .223/5.56 mags myself but .300 isn't something I have shot much yet.
 
with heavier bullets (180gr +) 556 mags do not work reliably. The follower and internal ribs on the mag interfere with the heavy projectile.
 
gvanzeggelaar said:
with heavier bullets (180gr +) 556 mags do not work reliably. The follower and internal ribs on the mag interfere with the heavy projectile.
Click to expand...

I have heard that too, I load 230 SMK and 247grn LRN with no feeding issues using Magpul M3 and LAR mags. I am only a few thousands rounds into playing with it though.
 
Loading factory 125gr fmj into MFT 10rd mags works great in my 300 Blackout. Have not tried anything heavier in that mag, as noted above I believe it is the internal rails/ribs that have been tweaked to better feed the BO. The MFT 223 mag rims push the rounds slightly "toed in" but that doesn't seem to affect feeding in my straight pull.
 
300BO feed lips, follower, and internal stabilization ribs are different on pmags. Maybe the front notch also


pmag300feed.jpg


d7RAeSh.jpg


 
Last edited:
You must log in or register to reply here.
Back
Top Bottom