So one of my buddies calls me up yesterday afternoon, says he blew up his new Ruger SR1911 Commander Lightweight, that "the round just went off in the magazine." My immediate first thought was "No it didn't."
So grab my trusty Brownell's red toolbox and head out to his place. He was insistent that he fired and the 1911 cycled and ejected but the next round went off in the magazine. Blew off the bottom grip screws on each side. Couldn't retract the slide but about 1/4".
He also said that when he pulled the mag out, the next cartridge was still in place with the side blown out and the bullet still in place.
Also very insistent that he loaded 4.5gr of Power Pistol, with regular LPP and a 230gr FMJ.
When I looked, first thing I did was shine a light into the chamber witness hole that Ruger has on their SR1911s: yup, case still in the chamber. Took the nylon side of the Brownell's hammer and was able to get the slide off the frame and we knocked out the case. The case head had blown out and down into the magazine.
Speculation now but it appears that the force from the BOOM cranked down on the next cartridge, smashed it against the rear of the magazine with enough force to pop the primer and ignite the powder. Both combined charges blew out the bottom of the grips.
All theory at this point, so I texted up brother Hemi with the following photos. He stated the same, that the case in the chamber blew out by the loading ramp and that it was most likely a double charge of powder.
Using my buddy's calipers, we measured both the slide rails and frame rails. Both had a slight swelling of a couple of thousandths of an inch near the feed ramp if in battery. When trying the slide to frame fit afterwards, there was a binding between the frame/slide forward of the battery position. After I left, he cleaned it and said the binding is gone and everything moves well and clear.
There were no visible cracks or other damage to the naked eye, other than the one lower grip screw he found had the lower 2 threads stripped off. The grip bushings were fine. Grips were fine. Hard to see in the photo, the top round in the mag that went off imprinted the case head shape onto the magazine!
I have to say, having read that Ruger made the slide and barrel from one solid forged piece of steel, I now believe it. Pretty damn strong!
Be careful reloading! Check, double check, recheck!
You can see in the one slide photo the bit of primer cup that is stuck in the firing pin hole.
Thanks again Hemi!