Originally Posted by Riflecrank
Quote
The 458 WCF looks like a great conversion. A friend has an early 71 with a terribly pitted barrel. This cartridge looks to be the perfect solution. Who does this conversion? Hopefully they can use the original barrel. Is there a 40 caliber version of this non blown out conversion?


That .458 WCF is just a figment of wildcat fever dying slowly within me.
Somebody has probably done it before, since the .348 WCF has been necked up to all larger calibers including .510".

Actually you have to blow the case body out a little to form that shoulder where it is.
Surprisingly it is almost the same capacity as the .450 Alaskan, which is just a few grains smaller than the .458 WM in gross water case capacity.

Start with a .50 Alaskan from Starline use some Imperial Sizing Wax on it and work it far enough into the .45-75 WCF FL die to produce a caliber-length neck.

Dave Manson could make the reamer. Custom reloading dies.
Even if the COL is limited by the lever action,
I would have that reamer throated like a SAAMI .458 WM, for many reasons.

All the .348 AI and 45/348 AI and 45 Alaskan and 50 Alaskan reamers drawings I have seen have very short/tight throats.

The .348 WCF has basically no throat.
The SAAMI chamber is only 0.010" longer than maximum brass length, with a 45-degree chamfer down to 0.346" diameter before the leade starts.
Therefore any throat beyond the chamber mouth is smaller than groove diameter and bullet diameter.
You would see partial rifling starting right at the end of the chamber case mouth !
Basically no throat.
Trim that brass religiously for a .348 WCF !
maybe the AI is good for something, reducing case stretching and need for trimming.
It would really be a humdinger if it had a longer throat.
The Dave Kiff/PT&G reamer for the .348 AI is leade-only starting at 0.349" diameter right at chamber mouth and tapering to bore diameter at 1*30'00" angle,
zero parallel-sided freebore, again, basically no throat.


I did a 450 AK conversion on my M1985G 45-70 just recently, and it has been wonderful. Feeds flawlessly, only needed to lengthen the loading gate slightly, to be able to load 2.64" COL, if I stay with 2.55" COL then no mods at all.
It feeds them as fast as I can move the lever, never jams. I did all the work myself, including smoothing out the action, I have the tools and mills to do it all, so for me it was a no brainer.

People have asked why do it, including my brother..basically this is the only way to get more MV without excessive pressure. Keep the load within the 44.5K and you can push a 400 grainer to 2100fs which is 450/400 NE loads. This is about 3900 to 4100 FPE. If you match the P+ 45-70 loads, you keep the pressures down below 40k..which is easier on the gun, and why I mostly did it, to save the gun.

577nitro