Rifling marks?

[BAGTIC]

Do recovered paper patched bullets retain an impression of the barrel's rifling or are they a bare smooth 'stealth' bullet?

[Harter66]

Lead boolits will have lands and grooves but the paper doesn't allow the highly defined ''signiture'' unless it slumps above the paper. 303 Guy has lots of pictures of the above as well as base powder peening. Harder projectiles would tend to mark less ,IE, a jacketed 277-8 patched up to 284-6 or a steel jacket in 308 up to 312-4 would have next to no marks.

[303Guy]

73865 Sometimes it's hard to see. [smilie=1:


73866
This one was a half patch so it shows the difference between a naked boolit bore impression and the patched impression. The forward section obturated so that's why it looks slightly bigger than the patched section - it is bigger.


73867
These two are an alloy/pressure test I did, the idea being to check for mid section obturation without nose slump. I used the equivalent of Red Dot for the test because it keeps the velocity low enough to capture the boolit intact. The first one is basically intact with no mid-section bump up while the second with a higher charge has fully obturated without nose slump. It also shows rifling impression through the patch. (Now if I can just replicate this with rifle powder .... ). It does demonstrate that smokeless powder does bump up a cast boolit.

[Harter66]

Thanks 303, your pics are amazing.