Lighter cast bullet in 300blackout.

[Maher1510]

I have the rcbs 7.62x130 spl bullet mold and they weight almost exactly at 140grs powder coated, sized, and gas checked. My question is I have LilGun and don’t really know how many grains of powder to start with. I want to start low but what do you think is a good starting point? It’s a 300blackout pistol. Thanks for y’alls input.

 

[Park ranger]

I use 16 of lilgun for 140 nosler CC. That's warm in my gun. Not sure how that relates to cast.

 

[Maher1510]

I was thinking starting off somewhere around 11 1/2 grains of lilgun but didn’t know if anyone else has used this cast for 300 blackout here.

 

[Park ranger]

That's going to leave a good bit of room in the case. My experience is LG is kind of weird, spiky pressure. Might want to try 4227 or even AA1600. 4227 is a Slower power and more bulky.

Again, I dont shoot cast so I'm worthless for you here.

 

[j8064]

OP,

I've not used the same bullet but one close. I shoot 150 gr pills cast from a Lee .311 mold and sized to .309. And I've not tried 'Lil Gun. I use IMR-4227 like Park Ranger suggests. The combo has given me excellent performance and accuracy in both my AR platform and Ruger American Ranch rifles.

Best of luck working up a load for yours.

 

[John from MD]

I have the rcbs 7.62x130 spl bullet mold and they weight almost exactly at 140grs powder coated, sized, and gas checked. My question is I have LilGun and don’t really know how many grains of powder to start with. I want to start low but what do you think is a good starting point? It’s a 300blackout pistol. Thanks for y’alls input.

I shoot 150gn cast with 16.5 gn of H110 and 17.0 of Lilgun. I'd say start at 15gns and go from there. Hogdon says you can go from 15.1 to 17.8 with 140gn bullets.

 

[John from MD]

I was thinking starting off somewhere around 11 1/2 grains of lilgun but didn’t know if anyone else has used this cast for 300 blackout here.

Way too low. It won't cycle.

 

[John from MD]

I use 16 of lilgun for 140 nosler CC. That's warm in my gun. Not sure how that relates to cast.

Cast can be shot at any jacketed velocity without worrying about pressure. The cast alloy has to be able to take the velocity however.

 

[John from MD]

4227 is slow in a rifle. In a pistol I think it will be worse.

 

[Park ranger]

4227 is slow in a rifle. In a pistol I think it will be worse.

A 150 SMK with 17.5 grains of 4227 is a tad over 1800 fps in my 16" gun. That not speedy, but the ES and SD are very low.

Same gun, 16 grains of lilgun pushes that 140 at 2000 fps.

But my favorite load is a 110 barnes tacx with 19 grains of lilgun at 2300 fps.

Sorry OP, but data is data, maybe it can help.

 

[outrider58]

Great discussion guys.

 

[Maher1510]

I’ll make a few at 15grs of LilGun and go from there. Thanks y’all!