Light vs Heavy and Extreme Spread

[deertroy1]

Thanks for all the replies. I replaced my firing pin assembly but it made no difference. I guess it's time to try heavier bullets.
I have tried finding a node with several powders. No luck yet.
I think the chronograph is okay as I have a smokeless muzzleloader and other rifles that regularly shoots low ES.
There are no doughnuts on my brass. I've also tried new brass.

 

[Mike Matteson]

I am getting here late but, bedding of the action is done? Is there pressure from the forearm against the barrel? I have generally found that the barrel like to be free float, but not all.

 

[HARPERC]

....I would replace your fireing pin and spring, as it has been modified........Cratering is likely not totally due to the firing pin shape, if protrusion is good and you want it gone then have your firing pin bushed. Sloppy firing pin holes cause craters.....As far as velocity spread, if you want it more consistent with the lighter bullets, after you have tried all that you stated, and it still doesn't work with the light pills but does with the heavies, it simply doesn't like the light bullets....,,Get a new barrel. After all that load developement and being rechambered, your barrel may be getting towards the end anyway....,,,

I'd start with the changes Cody suggested, whatever you do about the barrel this needs fixed.

Round count, and bore scope sounds relevant.

I've had good luck with H4831sc, and Federal 215's, and 70 grain Sierra Blitz Kings.

Curious about barrel length, I didn't see it.

Good Luck!

 

[deertroy1]

I missed it when I read Cody's earlier post. My barrel isn't rechambered. The rifle started life as a 243 Win. I put a new barrel on it. The barrel is a 22" McGowen. Round count is about 400. As mentioned I replaced the firing pin assembly.

 

[deertroy1]

So apparently this is only with the lighter weight bullets. I loaded up some 90gr A-Bonds and B-Tips. Had a couple three shot strings with 0 ES and 2 ES and most were in the single digits.