25x45 or 25/223

[320pf]

Here is a photo of the 6.35x43mm wildcat. It is basically a 223 Rem necked up to 25 cal and shortened (~2mm) from 45mm to 43mm. I had to shorten the case a bit so when the bullets are seated deep enough to fit in an AR15 mag. the case mouth does not ride up too far on the bullet ogive.

CH-4D had a set of 25-223 dies in stock so I was able to put together several dummy rounds and see how they fit in an Ar15 mag. Others have had reamers made for this wildcat so the reamer drawing only have to be modified to accommodate the throat and lead. Kurtz gave me some suggestions and for throat and lead dimensions... The drawing is pretty much finalized, so on Monday the drawing and dummy rounds go off to PTG.... Hopefully, in about 4-6 weeks I get my reamer.



The reloading data for the 257 Kimber listed below should give one an idea of the velocity potential. I am going to build a 20" barrel for this cartridge so I expect to get velocities about 75 to 100 fps slower than those listed below.

257 Kimber (a.k.a. Copperhead) Barrel Length: 22"
Bullet--------Powder---- Grs.------Vel. (ft/s) Grs. Vel. (ft/s)
75GR. HDY HP---H335------28.0------2769---------31.5------3195
75GR. HDY HP---H4895-----28.0------2756---------31.5------3192
75GR. HDY HP---H322------28.0------2806---------31.5------3198
87GR. HDY SP---H335------29.0------2870---------31.0------3030
87GR. HDY SP---H4895-----29.0------2824---------31.0------3056
87GR. HDY SP---H322------25.0------2604---------28.0------2868
100GR. HDY SP--H4895-----26.0------2527---------28.0------2760



From Left to RIght.Black Hills 69g 223, 100g Sierra MK, 6.35x43mm w/100g Sierra MK, 100g Sierra GK, 6.35x43mm w/100g Sierra GK, 75g Hornady V-Max, 6.35x43mm w/75g Hornady V-Max, 85g Nosler Ballistic Tip, 6.35x43mm w/85g Nosler BT, 100g Sierra Pro-Hunter, 6.35x43mm w/100g Sierra Pro-Hunter, unloaded 6.35x43mm case, and Black Hills 77g 223.

Thanks for your time,

320pf