.280 Ross loads for retumbo?

[bagograss]

In the COTW book I have it has 4350 powder but it don't say imr. is this the same powder as imr 4350 that's sold nowadays? I'm using 56gr imr4350 with a 154gr bullet and it has a load listed for 60gr with a 160gr bullet. I've gone as high as 58gr imr4350 but I started having real flat primers with the Winchester primer not so bad with cci tho.

[CINDERS]

Use this and go from there but I strongly suggest you heed discretion I got caught once with experimenting thankfully the bolt held together and stayed in the action remember the Ross is an old weapon of who's past you know nothing of unless it has been in your family since new.
https://www.google.com.au/url?sa=t&r...Kl4T5S-vM8pnpQ

[bagograss]

My m10 was actually bought new in 1916 by my great grandfather but it's been sitting for about 40 years till I started reloading for it. It shoots the kynoch rounds really nice but I don't have many of them. Thanks for the link.

[rcathey]

Just got done reading through the Wikipedia page for this round. Quite impressive round and a pretty big innovation at the time, sounds like.
I must confess, it’s news to me. I’m glad you posted about it!

[wjw]

You may want to check out an article by Jim Foral in the "2002 Gun Digest" where he gives instructions at the end of the article on case forming and loading. He suggests using data for the 7x61 Sharpe and Hart to load for the .280 Ross as the case capacity is the same. 7x61 data, while scarce, is more readily available than .280 Ross data. Some of the loads given for the COTW tend to be somewhat warm in both Ross rifles and also those listed for a .256 Newton. Have been using 67gr of H-4831 behind a 160 gr bullet bumped up to .289 in one of my Ross's in both Kynoch and reformed .300 Winchester Magnum cases. Same load in the other one with .284 diameter bullets as it does not accept the bumped bullets.

[browningautorifle]

Once again I caution you, if you're already seeing flattened primers...be careful of your practises. You're way up on pressures and will never know how high without the pressure test gear.

[bagograss]

How many reloads do you get with the 300 win mag brass? I've used that brass before buy had head separation after just 2 reloads. I've been using 375 ruger brass with way better case life just a little harder to form. My bore is 287 when I slugged it. It keyholes with .284 bullets. Do you know your bore size on the one you shoot .289 in?

[wjw]

Have 9 reloads with the reformed .300 Winchester brass and no losses (old Winchester cases). When forming, size my cases so they just enter the chamber and can then neck size with a 7mm Rem. Mag die. Do the same with my Kynoch cases but my supply of Berdan primers has has been reduced substantially and the last lot does not appear to be hot enough to consistently ignite the powder charge. Haven't been able to get the 375 Ruger cases - seem to be back ordered at the local shop. For your information, the Kynoch bullets I have measure between .276 to .277.

[bagograss]

Just wondering was that meant to be .286 to.287?

[wjw]

bagogras

Your assumption is correct - should read .286 to .287