interesting powder 'print'

[lledwod]

Here are two photo's of a 140 grn Nosler Partition recovered from a mule deer doe. I found the bullet in the snow about 60yds beyond the deer after it had passed through on a 121 yd shot. I believe the front core separated after striking the gravel under the snow. Now I wish I had looked for the front core too. What caught my eye is what appears to me to be the print on the back of the bullet of the powder column. (48 grns of 4350) in a 7x57. Any thoughts?

 

[broncoo]

is that a compressed load?

 

[Camp Cook]

Either that or the powder in the front of the case resting against the bullet did not burn immediately when fired and was pushed against the lead.

 

['Boo]

Pretty normal if that was a compressed load using "stick" type powder. .

I have seen the same markings on the exposed lead base off Partitions that were pulled from loaded cartridges.

 

[lledwod]

I did not think it was a compressed load, but will check that.

 

[shredder0]

Normal. I see that on the base of my recovered 200 grain partitions and they are not compressed loads at all. I use IMR 4350. I will make a giant leap and assume that the powder when igniting from the rear, thrusts forward and makes the impression on the soft lead of the base. If anyone has seen slow motion photography of this event occurring inside the case and can correct me please do.......

 

[lledwod]

Shredder0, your assumption is the one a came to as well, I have just never seen this before as I have not shot lead based bullets before these partitions. I imagine the primer ignites the rear of the powder column and shoves the front of the column into the rear of the bullet before the whole charge has ignited. Would be cool indeed to see a slow-mo video of this...but can't see how that would be accomplished!