A friend of mine purchased a used Dakota rifle from an estate. It's marked 7mm/300 wby on the barrel. I reload his wildcats for him but I'm having a problem with this one. I purchased a set of dies from CH4D and some once fired 300 wby mag brass I've FL sized the brass and I can't get the action to close on brass or a loaded round. I've done a chamber casting and with my measuring abilities, it looks right. I'd like to purchase a couple pieces of brass from someone that has been FL sized so I can narrow down the problem. If your brass chambers then I have a brass or die issue. If it won't, I figure I've got a headspace/chamber issue. Can anyone part with a couple pieces of brass? Or see something that I've missed?
7mm/300 wby HELP
- Thread starter tking308
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Lefty7mmstw
Well-Known Member
Why don't you neck down a couple of 300 h@h brass to 7mm and fireform a few with mild loads to make brass your rifle could actually use and then check the dimension differences.
I'm trying to verify what exactly is wrong. I figured if someone else's 7/300ebay brass fit, then I had a sizing die issue.
Lefty7mmstw
Well-Known Member
yep, I get that, but if you can compare the brass from the die to brass that is known to fit (the ones you just fire formed), you will be able to see what is wrong.
Forgive my ignorance but I'm currently comparing the chamber casting I did to the sized brass and I can't find any differences. I may not be able measure accurately enough to compare the 2.
Lefty7mmstw
Well-Known Member
how about belt height? some weatherby brass is rather tall at the belt; I've had issues with reforming weatherby brass to standard calibers because the belt is rather tall compared with win and rem brass. I found a few 257 wby once and reformed them but they bound in the 7rem I formed them for; I tossed the brass instead of fuddling around. Just an observation and all are probably within headspace spec., but I'd try fire forming necked down 300 h@h before I give up on the dies...
I'd also sharpie a round of formed brass to see where the bind is if it will even start to chamber. The hard contact will scrape off the sharpie and will give you a better idea of what you are up against for binding.
Lefty7mmstw
Well-Known Member
Some people love chamber castings because they should show the problems with dimensions, but that isn't always the case. I had a 7rum a number of years ago that rem had messed up on and belled the tail of the chamber. The brass was getting to .005" over spec. just forward of the web, but rem. couldn't see it in the chamber cast and wouldn't help with the barrel replacement. I ended up giving the rifle back to the gun shop and eventually got another 7rum. The rifle had split three sizing dies down the side because the fat brass was overstressing the sizing die.
Well it sounds like the consensus is to try some 300 h&h. I'll see if I can find some of that brass. Unfortunately a call to Dakota revealed that this rifle was sold as an action only... the only clue to the maker are the initials BAE stamped in the barrel and action.
