What velocity can I expect to achieve in 300 Blk with GC CBs?

[atl5029]

For those of you guys that cast for, load, and shoot the 300 Blackout, can you tell me what muzzle velocity I can expect to achieve with a gas checked 125-130 grain bullet? The alloy I was thinking of using was the 6% tin 2% antimony "hard ball" from rotometals. Hodgedon's website lists velocities around 2000-2200 fps for bullets of that weight. Could I get that without leading my barrel with a gas checked bullet?

Not sure what kind of coating or lube I will use. Most likely powder coat or pan lube.

Thanks!

[Blammer]

I'd venture to say. Yes you can.

[blueeyephil]

Just interested in what cast bullets you are going to use. I'm fairly new to 300 BLK myself and I have the Lee 155 gr I'm working with for plinking but would like to explore the lighter cast.

[rda72927]

I'm running a little heavier plinking bullet, Lyman 311041 173gn FP (COWW air cooled) at 1750 fps with very good results in (2) different 300 BLKOUTs.

[Butchman205]

Powder coat is the way to go IMHO. Shoots clean with good performance well over 2200 fps from what I've seen. 2200 is a good speed to expect with 300 blackouts from a 16" barrel, if using 125-130gr pills.

I've ran several weights of cast boolits (powder coated) until I'm getting flattening on the primers...with no leading.

Powder coating (again IMHO)...is hard to beat.

[Jupiter7]

Accuracy would be of concern, alloy content aside, about 2200-2250 is max. Depending on platform, bullets that short may not feed well from magazine. Most run 150grn+ in the 2000fps range with cast supers.

[atl5029]

Just interested in what cast bullets you are going to use. I'm fairly new to 300 BLK myself and I have the Lee 155 gr I'm working with for plinking but would like to explore the lighter cast.

From what I've read on here it seems a lot of people use the Lee 155 grain .312 diameter designed for the 7.62x39. I was browsing Midway USA's 30 cal molds, and I found the RCBS 7.62mm-130-SPL. Looks like a good blackout bullet for supers according to the reviews.

Boolit mold link;

http://www.midwayusa.com/product/305808/rcbs-2-cavity-bullet-mold-762mm-130-spl-762-mm-30-caliber-309-diameter-130-grain-spitzer-point-gas-check

[atl5029]

I'm running a little heavier plinking bullet, Lyman 311041 173gn FP (COWW air cooled) at 1750 fps with very good results in (2) different 300 BLKOUTs.

Do you GC your bullets even though they are fairly heavy for supers? Lube or coat?

[rda72927]

I GC and pan lube. They look short loaded but have not had any feed issues out of either gun. My brother got to test them last weekend and had a great time busting eggs at 50 yds and ringing an 8in medal plate at 100 yds. Loading 15gns of H110, COL 1.940