Wilson Combat 300 Hammer is now SAAMI accepted.

[Old Bob]

I don't have a 300 HAM'R but I do have a 7.62X40WT also made by Wilson Combat. Yup, the 300 HAM'R will require mags for the 300BLK or modified .223 Rem/5.56 NATO mags. I have some of both... the PMAGs & modified Lancer mags sold by WC. The modification is the milling down of the first ribs at the front of the mag to compensate for the wider 30 cal bullets.

From my experience with these mags, the feed ramps on my Wilson Combat barrel & various bullets I've used for reloads, it really functions quite well. I've had no issues at all feeding ammo from those mags. I've even used blunt, round nosed 110gr 30 Carbine bullets & they functioned perfectly. I thought they might hang up at the feed ramps but they don't. However, I must add YMMV. They work in my rifle... I can't say they will in all rifles.

[Texcl2]

So I’ve built 2 300 ham’r rifles and am in the process of building my 3rd. I’m sold on this caliber, it’s so much easier to get results with than the 7.62x39 or even 6.5 grendel. I love the grendel but for medium sized game at normal hunting ranges The ham’r makes a lot of sense. My 2 rifles shoot sub moa and are light, handy and light recoiling. There’s tons of .308 projectiles out there that will work but it’s sweet spot is 120-135gr. I use magpul 300 blk out mags and function is 100% plus there aren’t the bolt and extractor issues that 7.62x39 based cartridges have. I’m not sure why but recoil is lighter than any of my 7.62x39 ar’s or my 6.5’s. Did I mention this caliber is accurate? Lol. My favorite thing is the utility of being able to convert 5.56 brass and the only non 5.56 parts needed are the barrel and magazine.

My Grendels shoot fantastically and I have hunted everything from coyotes to elk with them but for most folks the 300 ham’r makes more sense IF they start mass producing ammo. It’s just easier and cheaper to run vs 6.8, 7.62 or 6.5 grendel. One last thing is once the brass is converted (which is super easy) it lasts forever. I don’t even anneal them anymore during the forming process.

[brando]

Sighted mine in today. Shoots great I have one issue I’m not smart enough for. I was loading one round into my Lancer 300 blk mags (10 rounder). And after the shot my bolt is hanging up on the mag instead of the bolt catch. If I pull handle back it will hit catch and stay there. Loaded three rounds to shoot some groups ... and it cycled the ammo fine but at last shot same thing. Brass is landing roughly 4-430 for me I have an armaspec stealth buffer H equivalent Wondering if I just need to drop to standard buffer weight??

[Klem]

Sighted mine in today. Shoots great I have one issue I’m not smart enough for. I was loading one round into my Lancer 300 blk mags (10 rounder). And after the shot my bolt is hanging up on the mag instead of the bolt catch. If I pull handle back it will hit catch and stay there. Loaded three rounds to shoot some groups ... and it cycled the ammo fine but at last shot same thing. Brass is landing roughly 4-430 for me I have an armaspec stealth buffer H equivalent Wondering if I just need to drop to standard buffer weight??

This is a familiar issue across AR calibres. You need more gas or a lighter buffer system. Sounds like it's easier to drop the buffer weight.

[Texcl2]

Do you have an intermediate gassed 18” barrel by chance?

[brando]

Mine is a 16” with mid. I kind of half ass knew I should’ve just went the standard buffer. But I’m going to run this gun suppressed. I thought that stuffer might help when that finally gets to me after my wait period. I’ll get over to JSE Tuesday and swap my buffer I bought. Gas block in not an adjustable one

Thanks guys!

[Texcl2]

My 16” mid is running a standard carbine buffer/spring, it runs everything, even 150 grain loads my intermediate rifle wouldn’t lock back with. I found out later that the cheap bcg I was using in the intermediate gassed rifle was leaking gas badly at the key (sealant not applied properly), once I switched it out with a new Aim bcg it worked fine with everything. Bill Wilson offered to look at the upper and possibility drill out the gas port if the bcg didn’t work and it’s not even one of their uppers, only the barrel is Wilson, great service!

[brando]

Yeah. I’m on that Texas thread too I haven’t mentioned it cuz it feels weird having Wilson on there although I’m not sure Shaw doesn’t make the barrels for Wilson.??Maybe not . But my complete upper is from Shaw I bet it’s the stupid H weight buffer I bought. I’ll try that

[Texcl2]

No, Wilson makes most of his own barrels start to finish, Ive heard some say the less popular calibers may be from other manufacturers but have seen no proof. They have a video of them making barrels from bar stock on their site.

Yeah, it could be the buffer, It’s hard to tell with home builds since there are so many parts variations. I’ve noticed a vast difference in carbine spring power between manufacturers, I try to stick with aero buffer/extension part kits but right now they are hard to find. The only reason I ended up with that no name faulty bcg was because it was all I could find at the time. At least it’s fixable I guess. I usually buy Aim BCG’s, they are made by tool craft and I’ve always had really good luck with them.

[sneaky one]

I have the 7.62 x 40 from wilson. It was the original start of making the 300 HMR. It runs best with a std. wt buffer., or 1 that's a bit lighter. Std. spring is fine.