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Posted: 4/2/2017 8:26:34 PM EDT
I just completed a .460 Rowland conversion on a High Standard 1911. I test fired the gun first with a mag of .45 ACP to check for proper lower lug contact on the VIS. I got a good looking bowtie contact area so that was good.

The I fired 5 full power .460 R loads and gun functioned fine and all seemed good. Later looking over the .460 cases I noticed a problem. As you can see in the pic below ( far left is one of the .45ACP and then 3 .460R)

The .45 shows a rather deep FP indent ( all the .45's were like this) the next is an obvious pierced primer and the other two the indent is filled with what appears to be brass from the case.



The .460 case, when plunked, sits .003" lower than the back edge of the hood. The hood to breech face clearance is also about .003", so .006" headspace play.

when pushed through from the striker of the slide the FP protrudes .325", this is the same on my RIA 1911 for comparison.

Upper recoil lugs engage .055" so that is more than good.

I fitted the slide stop by hand until the thumb safety would engage nice but snug.

I'm guessing that all the .460's I fired had their primers pierced and that the indent were filled with vaporized brass from the escaping gasses.

The primers really don't shows signs of over pressure.

So what's happening here and how do I fix it. Both the .45 and .460 were commercial loads.
Link Posted: 4/2/2017 8:43:09 PM EDT
[#1]
Those primers look like the primers did in my 9x23 mm Winchester when I had a titanium firing pin installed.

The problem went away when I switched to a conventional steel firing pin.

May not be a similar situation, though.
Link Posted: 4/2/2017 9:00:37 PM EDT
[#2]
standard stock FP
A pic of the FP
Link Posted: 4/10/2017 12:05:30 PM EDT
[#3]
Diameter at front of pin?

The .38 super pin is smaller for a reason.  Higher pressure.

I have not seen a number for blanking of handgun priers.

Rifle primers blank around 80,000 PSI.

Pistol primers are usually softer brass.


It does not take all that many primer failures to damage the tip of a firing pin and start to mark up a breech face with pitting.
Link Posted: 4/14/2017 7:08:30 PM EDT
[#4]
Yeah, Rowland says to use a .067" FP vs The standard .092" pin. I found changing the firing pin stop with the large radius to one with a very small one retards the slide and helps a lot too. The high pressure leads to primer flow which is the main problem here. I just got a .067 pin and extra power pin spring, just need to try it now.
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