#69212
popper
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McGowan or X-caliber HBAR carbine 1:11,12 280$ normal or 5 grove.

Took a while to get mine from McGowan (220$ IIRC and they put it together for me), several years ago but a good barrel.  I chose 10 as I use 10o – 190gr so it’s general purpose – and the slowest I could find at the time.

Let’s add a twist.  Larry uses 144k for the rpm threshold.  IIRC he uses mostly #2 alloy.  If you want softer alloy, you may want to go to the slower twist.  Bama found he didn’t smoke the fast stuff if he added copper to the alloy.  I used low Sb in my 1:8 pistol, pushed pretty hard and it worked, just Cu/Zn/Sb.  All my moulds are essentially smooth sided so lots of bearing surface.   So it’s not just stability for bullet length but fps & alloy too.

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