Just wondering what the deal is with different manufacturers varying so much on chamber, thoat dimensions for the same round. I have a sako 75 in .300 ultra that I can load out to 3.775" without tounching the lands.(3.8" to the lands) But my box only alows me to load to 3.7". Factory ammo is loaded to 3.585". That's a 215 thou. difference. Not optimum for accuracy. If I tried to stick one of those rounds in any other .300 ultra it probably wouldn't chamber. I have noticed most rifles vary this way. This may be a dumb question but my question is why? Shouldn't there be some sort of standard? If buddy got a hold of one of my .300ultra rounds and stuck it in his rifle it would over-pressure for sure assunming it would chamber. I won't list loads but they are over max listed in any manual because my overall length allows me to do this and my chamber is very generous to say the least. I just don't get why they aren't the same. A 3/4" bolt made by any manufacturer will fit a 3/4" nut made by any other. See my point?

I know what you mean about the long chambers of some rifles. I know a guy that bought a new Ruger M77 LSS in 300 Win Mag that I couldn't get the bullets anywhere near the lans because of the freebore, let alone get one to fit in the mag with it out that far. You didn't say what kind of accuracy you are getting with your 300RUM, is it decent? A long throat doesn't automatically render it to doorstop status as far as accuracy is concerned. Take a look at the Weatherby rifles chambered in any Weatherby Mag cartridge, they can be real shooters even with a freebore that would make reloaders cringe. I have an older custom built Belgian Mauser chambered in 308Norma Mag that has a long throat and tried loading the slugs out near the lans and it wouldn't group for nothing so I loaded some cheap ole Remmy Cor-lokts to about what the Norma factory ammo OAL and it put them into sub MOA. Let us know how that Sako shoots.

The rifle shoots great, once I started loading the bullets out farther. Have shot a couple 1/2" groups at 100. Shot one 5 shot at .45"(thats the one hanging on the wall) Usually more like 1.25". I just dont understand why there needs to be such drastic differences. We are talking about machined parts where .010" tolerences are considered very generous. No reason why there should be .3" differences between rifles for the same round. Just my opinion. There also should be a standard on magazine dimensions if you ask me.