Buffalo bore: 45 +p Auto Rim vs 45 super ??

[surfj40]

Buffalo bore has a 200gr auto rim that, according to buffalo bore specs on their website, matches their 45 super specs for the same 200gr bullet.

I would have thought the +p auto rim would match their +p acp in that same configuration.

So it seems their 200gr auto rim is the equivalent of their 45 super 200gr.

I got the +p 45auto rim for my 625 for woods carry only. Just found the specs interesting and a little surprising as I thought the supers would spec out higher than the +p.

Did I miss something in my schooling? If so, school me!!

 

[Bill Lear]

How many people in 2017 are likely to shoot AR ammo in an original revolver? Probably not many considering those who buy such guns tend to know their value and protect them. What this means is that AR ammo is ideal for any revolver built to use Moon clips in "the modern era" so to speak.

Modern AR and Auto ammo uses very strong, solid head brass easily capable of handling modern magnum pressure when properly supported. There is no "pressure" reason any modern revolver chambered for the .45 Auto/Auto Rim cannot handle loads substantially more potent than the rather modest-pressure .45 Auto load, and so Buffalo Bore is catering to a "known need" as it were.

 

[BLUEDOT37]

45AR (+P) -vs- 45 Super

Buffalo bore has a 200gr auto rim that, according to buffalo bore specs on their website, matches their 45 super specs for the same 200gr bullet.

...a little surprising as I thought the supers would spec out higher than the +p.

.

I'm going to suggest it's a matter of semantics.

First, there is no formal standardized (SAAMI) pressure for a 45 Auto Rim (+P) round, rather only as a standard pressure round listed in CUP (15K), not even listed in PSI.

Second, there is no formal standardized pressure set for the 45 Super. It's loosely defined as being in the 25K-28K PSI range.

Third, the 45 Super is a cartridge design, essentially the same dimensions as a 45ACP cartridge but made with a thicker web to handle the increased pressure in unsupposed chambers.

As a result the 45 Super has about 2% less case capacity than a 45ACP case (26.8gr -vs- 27.3grs H²O in Starline cases).

S-L 45ACP & 45AR cases have virtually the same case capacity.

S-L's 45AR cases are stated to be as strong as their 45 Colt case, which are stated to be as strong as their 44 Magnum case, & as such can easily handle 45 Super power loads, which I load routinely.

A 45AR loaded to 45 Super power doesn't make it a 45 Super cartridge. It makes it a 45AR (+P) which there is no standard for & can be anything over standard 45AR pressure. (A 45AR loaded to standard 45ACP pressure (21K psi) would be a 45AR (+P).)

Typically, neither round is loaded to modern "magnum" pressures.

Buffalo Bore uses Starlines cases for both the 45 Super & 45AR(+P) loads so they can be loaded to the same pressure, & termed differently, but be essentially the same, just in different cases.

Make sense?

.

 

[tommy F]

The new Sierra manual has a 45 ACP revolver section with the highest loadings I've seen. It also states all 45 ACP revolvers are strong. Another thing to consider is that all revolvers completely support the entire case to the rim, as autos cannot.

 

[buffhuntr]

I just picked up a 625-3 with a 4" barrel. I was looking at running the Buffalo Bore .45 Auto Rim +P loads in it occasionally for field carry. I've read that the .45 Super is too hot for the 625; part of the arguments presented being the cylinder walls are thin where the notches are cut out. Not sure of this an issue or just lore. But being that the .45 Super and .45 AR Buffalo Bore loads are almost identical I am curious if the .45 AR load is good to go.

 

[BLUEDOT37]

If you're referring to their 200gr JHP loads in their 45 Super & 45AR (+P), that the OP mentioned, yes BB quotes them as going the same general velocity, 1200fps.

So if you feel comfortable shooting one then the other is no different.

Buffalo Bore shows they tested them in a S&W 625MG, 325NG, Model 1917, & 1955s.

My handloads (45 Super & 45AR +P ) are as hot, or hotter than theirs and I've not had any issues in my revolvers (325NG, 325TR, 625-8). Others here have shot 45 Supers in their's longer, also without issues.

The cylinder stop notch is the thinnest point on these revolvers at ~.030" thickness, on my examples. On my .357 M66-8 they're .034". My 44 Mags run ~.039".

I'm unaware of anyone on this forum reporting bulged stop notches on their revolver from shooting 45 Supers in them.

For "occasional field" use, in a revolver in good condition, I don't suspect you'll have any issues either.

.

 

[stansdds]

I don't think I'd want to fire them in a vintage Colt or S&W model 1917. Metallurgy and heat treatments have improved greatly since then, so I'd stick with more recently produced 45 ACP revolvers for such ammo.

Just my two cents.

 

[cowboy4evr]

Cylinders don't fail where the " notch " in the cylinder is . They fail between the charge holes , at the web . I got this from a custom gun maker . Regards , Paul

 

[BLUEDOT37]

Makes you wonder why the manufacturers would go to the trouble to (re)locate the stop notches between the chambers (where the metal is thicker) if that's not the weakest point.

The metal between the chambers is twice as thick (~.064") as the metal at the stop notches in my modern S&W 45 revolvers.

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