I have decided to go with another magnum caliber and want to go with the .30 cal. I have narrowed it down to the 300 Win Mag and the 300 WSM. I would like some pros and cons on both of these and a direct comparison if anyone can provide that. The information that I read about the 300 WSM suggests that many are not getting the numbers published in the reloading manuals in terms of velocity. I am looking for the cartridge that will take game at the longest distance. I also read that some people have a hang up with the belted cartridge. I have never understood this. I have spent plenty of time behind a 7mm RM and never saw were the belt made any difference in terms of accuracy say compared to a 30-06. If I can get the velocity out of the 300 WSM, and since I can use the same bullets with both cartridges, what is the advantage of the 300 Win Mag, especially since I would be using less powder with the 300 WSM.
Basically, for the mid and low range weight bullets, there really isn't much difference (other than the WSM being more efficient and shorter action). For 180gr and up bullets, the 300WM will give you a little bit of an advantage in velocity.
You said "I am looking for the cartridge that will take game at the longest distance." The heavier bullets will be better at long range and the WM will push them harder. If you really want the .30 hotrod, what about the RUM, or the 30-378? Those will really push the envelope on those heavier pills.
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I agree with AJ. You said at the longest distance. The 300 win mag will push the 200 grain class bullets faster for long range work. I built a 300 wsm last year and am getting 3419 fps with a 150 grain bullet out of a 24.5" barrel. That is equal to the 300 win mag. But the wsm falls off with the heavier bullets. Those long bullets take up a lot of capacity in the short case. If you want to kill stuff a long way with a 30 caliber then get the 300 ultramag and push the 200 grainers at 3200 fps.
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If you really want to get out there, look at the .338 RUM and up. ballisticlly better at long range. if I was to go with something a little lighter recoil wise I really like the 7mm WSM or 7mm-300 WSM. sorry that that is not even close to what your question was asking, but I think that ballisticlly ther are better options. If I had to go for one or the other I would say whatever you find for a good deal or in the model your after.
I selected the 300 Win Mag because of the reasons already mentioned and because Lapua brass was available. Then Lapua stopped manufacturing 300 Win Mag brass about 1 year ago. But RWS still manufactures 300 Win Mag brass to the best of my knowledge, and it's as good of brass as Lapua. So I'd still go with the 300 Win Mag and use RWS brass with 210 gr Berger VLDs for long range hunting.
Thanks gentlemen. This helps. My goal is to push the heavier rounds, say above the 180 gr mark. I am really looking to stay with the 30 cal bullet, but I do appreciate the suggestions on the 7mm. I like the 30 cal over the 7mm just because I can use a heavier round. I really am looking for something to throw rounds that weigh over 200gr. It sounds as though the 300 Win Mag is the better option.
If I decide to build this rifle and not go with a factory model, what length barrel would you recommend as optimal? I am not that concerned about the weight, I am just looking for performance. Is a twist rate of 1 in 10 good for the heavier bullets, or does it need to be slower than this?
Food for thought, I just put together a 300 WSM round of 71 grns of H1000 w/ a 200 SMK. My velocity is 2922 avg. with an ES of 14fps. I am cutting .5 MOA or less with this bullet if I do my part on a stock SS 26" Savage 1:10 twist barrel. This load according to 1500 ft lbs puts me right at 920 for elk. I can get to 1300 for Whitetail with 1000 ft lbs. Just thougt I would put that out there. The 200grn. SMK has a BC of .570 according to a calculator I use.
There is a smith that I know that is using longer barrels with the 300 WSM and getting 3000+ fps. (30-32 inch Barrels), but these are all hand loaded rounds. If you went with a 1:12 twist barrel or even a custom 1:11 you would get better speed. If you went with anything heavier than the 200 grain round then you would definitely need a 1:10 twist. Not sure if you are a loader. The 300 Win Mag would probably push that round to about 3050 or more. Good luck on your decision.
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