Firing pin appears to be piercing primer

[RB II]

I would strongly suggest starting at 38 and work your way up .5 grain at a time, given the problems you have already had. Measure the velocity of each load and analyse the fps gain for each .5 grains of powder added. If you get to a spot where the gain is less than half the extra fps of the previous load gains, or worse zero gain, stop.

I have already done most of what you suggested. The loads I shot were
40 grs at 2984 fps
40.5 at 3001 is +17 fps
41 at 3044 is +43 fps
41.5 at 3052 is + 8 fps
42 at 3087 is + 35 fps
42.5 at 3129 + 42 fps.

So is 41.5 max load for this rifle with these load components. H4350, CCI 400, 103 ELD-X and Alpha brass?

 

[Dean2]

I would check out 39 and 39.5 as the 17 fps gain at 40.5 is a clue and indication you are topping out. For sure I would not go above 41 and all indications are that 41.5 is too hot already. I would be measuring case head expansion to verify pressure.

 

[RB II]

I would check out 39 and 39.5 as the 17 fps gain at 40.5 is a clue and indication you are topping out. For sure I would not go above 41 and all indications are that 41.5 is too hot already. I would be measuring case head expansion to verify pressure.

Thank you for your explanation.

 

[dustbag]

What about neck clearance. Can you fit a bullet in a fired case or is it tight?

 

[RB II]

What about neck clearance. Can you fit a bullet in a fired case or is it tight?

Yes, a bullet will slide easily in the fired cases.

 

[Roperboy87]

By looking at the brass right of the blown primer the primers appear to have lots of cradling my vote to hot of a charge. You chamber maybe be tighter so that could cause some of the issues.