First off I am a self admitted groundhog/rockchuck blasting addict, you name it I have killed them with it. From hand thrown rocks to .375 Ultra mags, oh yea I need help...My personal best is 176 in a summer...The two calibers I enjoyed blasting them with the most were the .243 Win and the 6mm Rem both with 75 gr V-max's, makes for instant orchard fertilizer...So I started thinking about what I felt would be the perfect chuck cartridge with out going overboard like I have been known to do. So I came up with a drawing called it the .257 Smack and sent it off to Pacific Tool & Gauge and had the reamer built.
To best sum it up I will be fire forming the cartridge from necked up Lapua .243 brass, blowing out the body and shoulder(37 degree) quite a bit. It will have a little more case capacity than a 25 Souper(25-308)...I decided to go with the 25 cal bullet due to the fact I can shoot the 75gr V-Max's and run the 115gr Berger VLD's for the long stuff and still use a Rem700 short action as a repeater. You can't run the heavier match bullets seated properly as a repeater on a Rem700 short action with the 25-284(To long)...
Bellow is a link to a photo comparing the .257 Smack go gauge(Right) to several other cartridges...I don't have the rifles completed yet so I do not have a fired case to show. This is all new to me, I'll figure it out as I go and hopefully have it all figured out by the time those stinking chucks poke their mangy heads out this spring.
In the photo from left to right... 6.5-284, .308 Win, .243 Win, 6mm Rem, .257 Smack go-gauge..
I will be trying/testing this cartridge with a SS 28" 10 twist med palma Bartlein barrel along with a 24' sporter weight version with the same specs SS 10 twist. I just wanted something different/original. I want those chucks this spring to be proud to be vaporized by a cartridge of the likes they or their distant relatives/family have never seen :-).