New build 300 BLK

[dj454]

Hey guys. I have been casting pistol bullets for about a year now and I have thought about getting into casting rifle as well. I was going to try casting for my AR 15 in 5.56 but after researching it the extra trouble of gas checking those little bullets doesn't seem worth the trouble.
I have decided to build a 300 BLK with a 16" barrel. I have started shooting a local 3 gun close quarters tactical match. I am interested in making some cast loads for the 300 BLK to help cut my costs. I have no plans to run a suppressor but I mainly interested in the heavy 220 bullets. I coat my pistol bullets with the Hi-Tek coating and I would imagine it would work fine for the slow heavy bullets in the 300 BLK.
The farthest distance we shoot is maybe 25 yards with a rifle so I am not interested in long range accuracy with this load.
I have been digging trying to find all the info I can before I spend a lot of money. It looks like Reloader 7 works well for the heavy bullets. But there isn't a lot of load data I can find. All the guys I know running the 300 BLK use jacketed bullets. I am concerned about leading and cycling and of course it has to be reasonably accurate. Thanks for any help.

[HATCH]

I do AA1680 and use a accurate molds 240E.
I cast them on my automated Master Caster and size them using a lee push thru .309 sizer.
I coat them twice using Hi-tek black 1035 and then size them.

No leading. My dad can put 3 shots in a nickle at 25 yards (longest indoor)

He shoots them out of a Remington 700 AAC 16 inch barrel bolt gun.
I plan to shot them out of a my SBR AR (10.5 inch barrel with a pistol gas system)

Now you were asking about cycling. I do 10.4 grains of AA1680 and it gives me 1078 FPS.
I have shot the factory Remington 220 grain jacketed across the chrony and its at 1050 FPS.
Both the above were out of the 16 inch barrel.
Based on the performance of the factory ammo (it being slower), I suspect that there shouldn't be any issues with the reloads cycling out of the AR 10.5 inch barrel.

[StromBusa]

I finally got my SBR blackout yesterday, I tried my 130 grain powdercoat load & it cycled fine...AAC MPW

[Colohunter]

I have loaded the Lee 309-230 in my 300 Whisper over AA 1680 and it cycles just fine in my 16" upper with carbine length gas. I haven't shot a lot of cast through it, but so far PC and LLA have worked just fine.

[Moonie]

We have 2 300BO uppers that have never had jacketed bullets run through them. Neither has ever leaded, barrel, port, tube, bolt tail or BC. Gas check for loads over 1,500, plain base for below. Over 1,000 shot through both, with just a bore snake run through the barrel on occasion. Regular cleaning for upper receiver and BCG.

We have shot 170gr Lee (checked, shot ok, feeding was an issue because of the short length), Lee 312-155 (checked, probably my favorite loading for this cartridge), Lee 230 (not impressed with it), 245gr Accurate ( Checked and unchecked, when loaded to the right length it is flawless in my Lancer mags) and will soon be shooting the new A.C.E. 230 through it.

[petroid]

Reloader 7 will work but it is a little too slow for blackout. Mine leaves unburned powder with anything less than a full case for supers. For subs the lee mold works fine. I PC but hitek should be similar. Start with 11.5 gr and confirm function and work down. H110/296, lil gun, any of the 680s should be fine. And IMR 4198 has load data but I haven't used it

[Moonie]

Yea, for supers I stick to H110/W296, for subs I've found RL-7 works well for me, but I do not have access to any of the 680's.

[sfcairborne]

Moonie,

Good morning, may I ask what charge your using for your subs. Ive got RL7 the 311165, 311414, 311247 Noe molds, and group buy Ace mold. Ive been running 10.2 5744 with the 208 Amax in both my AR and Bolt gun, but want to really use my cast. This is for my Rem 700 bolt. ive got my loads for my AR SBR, powders on hand, Rl7, h110/296. red dot, unique, bullseye, 231, 5744 and 1680 and trailboss, do a lot of loading for other calibers, hence the powder

Thanks

[wordsmith]

I run 10.0 gr WC 680 (Mil Pull Down roughly equivalent to AA 1680), 100% function in two 16" carbines and one 10.5" pistol length, 1035 fps (10.5"), NOE 311247 PB, Hi-Tek Gold two coats, sized to 0.309" with Lee Sizer. I've seen others use RL7 successfully for heavy subs, but I've not tried it.

[Moonie]

Moonie,

Good morning, may I ask what charge your using for your subs. Ive got RL7 the 311165, 311414, 311247 Noe molds, and group buy Ace mold. Ive been running 10.2 5744 with the 208 Amax in both my AR and Bolt gun, but want to really use my cast. This is for my Rem 700 bolt. ive got my loads for my AR SBR, powders on hand, Rl7, h110/296. red dot, unique, bullseye, 231, 5744 and 1680 and trailboss, do a lot of loading for other calibers, hence the powder

Thanks

Right around 11gr of RL-7 with 245gr boolits.