by 1gewehr » Sat Jul 06, 2013 11:38 am
It depends. Many of the Webleys in the US were cut to use .45acp with clips or the .45 Autorim. If yours was cut, it will not work with .455 Webley as the rounds will be too deep into the cylinder to fire reliably.
Many folks recommend downloading .45acp for these revolvers. Considering that many are nearly 100 years old and parts are getting very scarce, that's not bad advice. IIRC, the .455 Webley had a max pressure of ~13,000psi. The .45acp has an operating pressure of about 19,000psi.
Now, I've fired a bunch of factory .45acp from Webleys without ill effects. But, I don't do that any more as I don't want to take any chances with revolvers which are getting to be very valuable and scarce.
If your Webley was not cut for the .45acp, congratulations! It's worth a lot more. The kinda, sorta good news is that .455 cases are really easy to reload. The Fiocchi ammo is very high quality and cases last almost forever due to the low pressures. More good news is that due to low pressures and low velocity, leading of the bore is very rare. So you can use soft lead bullets without concern.
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