Cast bullets

[charlie b]

I know that when I go over 2100fps with either of the bullets I have used the most, the groups open up, just as yours seem to do. Above 2400fps the 210gn bullet is erratic. FWIW, 2400fps with a 210gn bullet in the .308 is right near max for jacketed at that weight.

Since my goal is MOA or under then I keep the speeds lower with the 1-10 twist.

Why was I pushing the velocity? I wanted to try for MOA at 600yd. I could almost get there at 500yd but the velocity is just barely supersonic. Past 500 they just kind 'scatter' :)

Sent from my SM-P613 using Tapatalk

[PhilC]

Don't need to run them any faster than necessary to punch holes in paper. My goal is sub-MOA groups without frustration and I achieved that at lower velocity in my 6.5CM.

I am quite content with sub-MOA groups @ 100yds shooting cast using simple techniques and processes. Larry's "rpm threshhold" may well be all BS but it worked for me when advice from others who disagreed him didn't.

Posted this in my 7BR topic, results of 10 competitors shooting 30BR at the 2021 CBA nationals suspect they know a thing or two about shooting cast and getting results...

9 of 10 used linotype
8 used Fed 205M, 1 used Win SR and 1 used Win SP
Avg barrel length - 24"
Avg twist - 12
Avg velocity - 1960fps
Avg boolit weight - 194.7gr
All competitors used lube and gas checks
3 used Varget, 2 used A2495, 2 used N135, 1ea used N133, IMR3031, IMR8208

The grand national champion shot a 30BR with a 12T 24" Shilen using 207gr boolit over 29gr A2495, Fed 205M, at a chrono'd velocity of 1750fps.

[charlie b]

Just typical frustration for me with cast. Nice groups with fliers. I am equal opportunity cause I do this with jacketed frequently as well. :)

[PhilC]

See my topic here for more info. 100yds with 6.5CM, 140gr Lyman 266469, shot during match this 10 shot group measured .882".

[Blue Avenger]

always have some .308, .38 S&W .357, .45 and .416 floating around the shop

[charlie b]

Question. Has anyone used moly based lube?

I've been trying some just to see how it does. Will go back to my standard (Ben's Red) to see if there is any performance difference.

[charlie b]

Some may have wondered about my not competing since some of my shooting looks pretty good. This is why. If I shoot a 5 round group I can sometimes get some pretty small ones. But, most competition is more than just 5 rounds. These are both 10 round groups. First round out on one, last round out on the other. Yes, both cases it was due to me lifting my head.




Yes, this is my .308 and both are 100yd, squares are 1/2". I was 'testing' myself and I failed :)

Bullet is the NOE XCB 310-165, lubed with Ben's Red. I was also comparing the performance of small primers (Peterson brass, Fed AR Match) and large primers (Lapua brass, WIN LRP). Both cases have the flash holes drilled out.