I posted a thread on the wrong forum. I have a 25-300WSM that I was waiting for factory ammunition to be available for. Now Winchester may make the 25 cal. on their super short magnum case instead of the longer WSM . I need loading data as I have begun necking down 270 WSM brass to do the job. Any one here have any suggestions.? 257 WBY start loads? 25-06 top loads? Help!
lb404

Don't use .257 Weatherby loads. That cartridge is larger and has freebore also.

Start with an internal program. There is freeware on the net for the Powley formula. One program tht has it is here in the AR archives as "LoadBase".

My internal program "Calculoader" shows H1000, RL22 and IMR 7828 as being best for 100 gr bullets in a 79 gr water capacity similar to the .257 Jamison.

You could use 25/06 data also but only for powders like 4064 and faster.

Good luck.

Ib404- I have a friend with this wildcat,i belive hae has started working up loads,ican give you his email if you are interested in sharing info with him.

diesel_dude, Absolutely would love to share information. I have quick load but the is NO substitution for real time data!
lb404

404;
have you looked at the Reloading pages listed on home page? At least you could get a rough Idea where to start.

IB404, I've got one, So far I've only experimented with RL-22 and 100gr Nosler Partitions. I started out with 59.5gr and worked up to 64.5gr with bullets 0.01 off the lands. It's got a tight neck (.290) and chamber. I ran out of loaded bullets before I got into over pressure territory but I think I was getting close. I've got all avg. velocities written down at the house but I can tell you this round is a screemer. With 64.5gr it averaged 3580FPS with a spread of 37FPS Terry

I have one, a sendero with a 29" barrel,should be shooting it this weekend for the first time, and will let you know.

Savage99, how do I get to the archives???,I would like to look at the internal programs, Loadbase, and calculoader, for some progects that I am working on, Thanks for the help

I'm sure anyone who frequents the forum has read my data all ready but since it was brought up again here it is. 115 Nosler ballistic tip 60 Grs. RL-25 = a little short of 3300 FPS. Groups averaged around .4" at 100 yards. If anyone else has info keep it coming we probably could all use it.

Mat