That 1917, at the time, would accept any military ball ammo, factory load. So, any new factory pack should not be a problem what so ever.

A bad box of factory Winchester ammo would be very rare encounter. I've purchased plenty of the white box bulk rounds (hardball) with never a bad round nor anything even remotely similar to your experience.

First, where did you buy the Ammo ? At a retail store or at a show ? Perhaps at a bargain table ?

Many times those who reload ammo just place them back in a factory box but usually a conscientious reloaders, re-labels the box, some old timers do not. That split case is usually relative to cases that have been reloaded several times and / or an oversized cylinder bore.

If you saved all the brass from that box of Winchester ammo, examine with magnifier for the head stamp markings to see if they all match. When I reload for precision target ammo, (e.g. Giles .45 Auto target loads which I used on model 25 target revolvers, too) I match and weigh all the same brand and type cases. However, for bulk reloads, I don't match cases to brand and type and / or weight.

That said, check the cylinder bores to see if the .45 Auto / .45 Auto Rim chamfers are still there or someone honed it out to a .45 LC. A correct cylinder bore gauge should be used but in absence of that a visual check may suffice. Take a new, factory .45 Auto place in cylinder at each of the 6 positions, one at time to determine if they fit properly or are bouncing around in there (loose fit).

Some of the home done, non-professional, boring out of the cylinder to accept .45 LC are just plain sloppy. Usually, a very visible roughness or evidence of a drill (home done) to drill out the chamfered area.

Take a .45 Cal mop, wet with any light oil of your choice (for a good reflection on cylinder bores) then take a properly focused and lighted photo of the cylinder bores, to post picture here.

Although if modified to accept .45 LC the face of the cylinder is sometimes "decked" but not always as there is usually sufficient headspace.

Can you read the serial number on the face of the cylinder clearly ?


This should be interesting to see.

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