FPS variance in loads

For one thing, the Hodgdon starting load data you used is for a grease lubed lead bullets.
But you are shooting Copper Plated bullets.

Copper has a higher coefficient of friction then greased lead.

Berry Bullets suggest you use low to mid-range jacketed bullet data, not lead bullet data, for that reason.

See this Berry FAQ for recommended load data to use:
http://www.berrysmfg.com/faq.aspx?n=633800

rc

Assuming 45acp...

I've loaded some really low velocity loads like JimGun. The bullet seems to roll down the barrel, fall aimlessly to the ground and walk over to the target, where it climbs up and lazily pokes a hole somewhere in the paper, then it goes and sits down somewhere for a rest.

At least that's what explains the random pattern of holes all over the target.

ants said:

I've loaded some really low velocity loads like JimGun. The bullet seems to roll down the barrel, fall aimlessly to the ground and walk over to the target, where it climbs up and lazily pokes a hole somewhere in the paper, then it goes and sits down somewhere for a rest.

At least that's what explains the random pattern of holes all over the target.

Click to expand...

I had something similar happen to me in trying to figure out if some strange primer signs in my 50GI 1911 were pressure signs or just artifact from the humoungous cartridge cycling in a 1911 gun. Since I wasn't about to use a $3,000 gun with heavier charges to see what happened, I came up with a unique and somewhat perverted solution. I shot my trial 50 GI loads in a 500 Smith with cut-up and ground down (to 20 mils) moon clips. Obviously, I could do anything i wanted here with a 50 GI and the gun wouldn't blow up. Now, the really revolting thing about doing this is that whn you fire the round, the bullet rattles down a full 1.5" of chamber before it hits the end of the cylinder and the forcing cone in the barrel. First load I shot chronoed at about 350 FPS, and there was a discernable pause between the BANG! and the SPLAT!! Didn't see the bullet stick its thumb out to hitch a ride, but maybe I just wasn't looking good enough. I ran the powder charges all the way up until I was getting 1,000 FPS out of the Smith, with the primer and the case looking fine, so whatever was going on in the 1911 was case motion atrifact. Alex Zimmerman, owner of Guncrafter industries, was both amused and grateful for my data.