Drank the .300 Black Out Kool-Aid (Again)
About 8 or 9 years ago, I built up a 300 BLK AR. I liked it, but brass and bullets were scarce and terribly expensive, so I gave up and sold the 300 upper and went back to 5.56 M4gery.
Well, I still hankered for a 300. I like the concept of a 7.62x39 like cartridge that uses 5.56 mags, which I have a multitude. .300 BLK brass and bullets have settled down to the price of good 5.56 brass and heavy .223 slugs (75 & 77s). Then two things happened at once which made me take the plunge again.
One, I started working part time at my friends gunshop. He had a bunch of factory .300 BLK ammo (Hornady American Gunner 125 HPs and Jamison 125 JSPs) at pre-panic prices. I grabbed 400 rounds. Secondly, PSA had a Daily Deal of a .300 BLK complete 16" carbine kit for $419 including a bolt of Carpenter 158 steel.
Came in only a week after ordering.: I put it on my JD Machine lower with Colt LPK, Phoenix Technologies California legal grip, and a pinned early CAR-15 type Fiberite stock. Replaced the flash hider with a no-name short brake, added no-name BUIS front and rear, and my old school Bushnell TRS-32 red dot. I'm a cheap old man and use what I have! Besides, the TRS-32 is a great red dot. I'd rather spend the money on ammo instead of fancy-dancy stuff... The BUIS is actually a decent pice of kit, made of steel and aircraft aluminum. Tight with no play when it locks up or down.
https://www.milsurps.com/images/impo.../YB7gmxL-1.jpg
Even though I have 400 rounds of factory 300 BLK, I don't want to take it to the range until I can try some of my handloads. I have 1000 rounds of brass, primers, 3 pounds of WW296, and 1,000 Hornady 125 HP (#30192) which is the same as they use in their American Gunner .300 BLK I have. I'll load up some the load I used before on my first 300 BLK: 125s with 19.2 of WW296 and see how she does.
I have dubbed it "Thumper" as an homage to Jeff Cooper, who came up with the concept of a Thumper (a compact, semi auto, 200 yard, large bore carbine. While he envisioned .44 Mag or .45 Winchester Mag for a cartridge, I think Jeff would have given the nod to the n.300 BLK. I'm 68 and this is my first high-tech handguard. I'm "old school" liking M1 Carbine and Mini-14 wood and steel, and early retro CAR-15 handguards and stocks. I wish I could afford a Mini-14 in 300, too.
For me, the use of my 5.56 mags was a plus. I tried a 7.62x39 AR upper a few year ago, but never found any magazines that were 100% reliable with the 7.62x39. The .300 BLK is close, with my 125 grain loads being 2200 (or 2300 FPS if I want to absolute max load it).
