Question regarding pressure and .45 convertibles

[Gary A]

I am curious about this. It is recommended that SAA clones such as Ubertis be kept to standard pressure .45 Colt loads which is, I believe, 14,000 psi. Some say that Uberti revolvers can safely handle up to 17,000 psi without problems. My question is regarding the extra .45 acp cylinder that is available for the Uberti and other makes of SAA. A standard 230 grain .45 acp is rated at 21,000 psi. Plus P is rated at 23,000 psi. I would not shoot +P .45 acp from my Uberti, but what is it that allows the safe shooting of a 21,000 psi load in a Uberti or USFA gun that is only recommended for 14,000 psi (or maybe a little more) in .45 Colt?

 

[Jim Watson]

Well, you could look at it the other way. Why should a gun made of modern materials be limited to black powder pressures the old mild steel revolvers were built for?

If Uberti sends out a gun with .45 ACP cylinder, it was proof tested for that round as a matter of Italian law.

If USFA sends out a gun with .45 ACP cylinder, surely they have done the equivalent in house, they don't want to get sued.

 

[jim147]

I have wondered about this myself but havn't been able to find a straight answer. Liability issuses I'm sure. But I do think the modern SAA clones should handle more pressure it would just take a careful load work up procedure.

 

[unspellable]

No manufacturer is going to admit that his revolver might take more than the SAAMI spec pressure. The legal department would have a fit. For that matter there are darn few that will admit you can use a hand load even at SAAMI spec pressure.

 

[Steve C]

There is a lot of difference between SAAMI maximum pressure for a cartridge and what its loaded to by the manufacturers, the only safe thing to say about factory ammo is it is no greater than SAAMI spec max pressure. Any modern revolver should easily withstand greater pressure than the old black powder guns, esp those manufactured in Europe where they pressure proof test all their guns.

The reason the Manufacturer only recommend standard loads is that they know their gun will hold up to them and since they don't have any control over reloads they usually void the warranty if they are used. Since there's no commercial manufactured ammo that's splits the pressure level of standard vrs Buffalo Bore Ruger only ammo the gun manufacturer (or importer) just want to CYA and not put themselves into a position of recommending loads greater than standard SAAMI pressures.

 

[Gary A]

Thanks, guys. Your answers follow along what I was thinking but didn't know. I'm not really interested in pushing the limits but was simply curious. I have two convertible revolvers, one being a Ruger Blackhawk. No questions about strength there, but I wondered about the Cimarron. Certainly I understand that Uberti and USFA and others would not offer the convertible cylinder if it was not safe. BTW, I chronographed a few S&B 230 grain ball and a few 230 grain Federal Hydrashoks "tactical" from a 4 5/8 inch Blackhawk. The Sellier & Belot ran from the high 700s to the low 800s, about what I might have expected. The Hydrashoks ran just below to just above 1,000 fps. Can't guarantee the accuracy of the chrony but the S&B ammo seemed about right. Wowsie! Shot very accurately and recoil was mild. I had fired a cylinder-ful (5 rds) of the Hydrashoks a few days before from the Cimarron and they were also easy to shoot and accurate. Based on this, I might only shoot this load rarely from the Cimarron. They are not listed as Plus P.