[Werewolf]

I reload .45ACP.

My two loads are:

1) 5.3gr HP38 under 230gr FMJ Fed 150 primer
2) 8.5gr AA#5 under 230gr FMJ Fed 150 primer

Both loads are well under SAAMI spec for the .45ACP according to published data.

I shoot load 1 out of my Sig and load 2 out of my S&W 1911.

When shooting load 1 out of the Sig I often find a small secondary dimple in the primer that intersects the firing pin dimple. In other words it kinda seems like the pin is hitting the primer twice. When shooting load 1 out of the 1911 no such double hit is happening.

Question: I shoot Hornady .45ACP +P 230gr XTP's out of the Sig and don't get the apparent double strike. Is this a double strike in the Sig resulting from high pressure or is something else going on?

I'm betting on something else since the load works fine in the 1911 and a +P load works fine in the Sig.

What could be happening here?

[cslinger]

I have heard that when SIGs fire the firing pin stays forward or whatever on the ejection, supposed to keep gunk out of the firing pin channel or something. This tends to cause either an additional mark or dimple on the spent brass.

[Jim Watson]

Firing pin skid marks seem to be common on SIG-Sauers, mine do.
It probably shows on your reloads because the Federal primers have softer cups than whatever Hornady is using.

[Black Snowman]

I think the 1st two nailed it. So I guess this post is just to increase my post count since all I'm doing is agreeing with them ;)