.308 vs .300WM

[Rumbler]

I'm dealing with third degree burns in parts of my body that don't need to have burns.

You need to wear some asbestos bubble wrap. Always.

[YankeeFingergasm]

I'm dealing with third degree burns in parts of my body that don't need to have burns.

You should try lotion. Going dry is for the birds.

[Jafar]

J, I was thinking about this more. In the recent past you mentioned the desire for a 'general purpose arm that could serve plausibly as a scout type rifle', paraphrasing obviously.

And it occurred to me that in order for the 300 winchester magnum to offer any significant ballistic advantage over the 7.62x51 or .308 cartridge at distance the 300 is going to need a longer barrel. There may be folks here who have researched the 300 more than I have but a little cursory math seems to indicate a minimum length of 26-28 inches will be needed. Less than that and you are pretty much getting slammed in the shoulder just to make a big muzzle flash.



Well . . you know; unless you are up for getting your shoulder badly abused while I do some load development for you.

I've got some ideas I'll run by you tomorrow.

[BlueBronco]

It hurts when im loading 27-28 grains of powder in a .223 case that would hurt my soul pulling the lever on a 75 gr charge with what powder is going for these days, im glad I got some 7.62x54r stocked up

My .22 centerfire bolt guns are .22-250 and .220 Swift. 4000+ fps.

[seadog]

IMO it depends on your objective. Take a look at energy downrange as well as trajectory and you might just find your answer there.

[Jafar]

IMO it depends on your objective. Take a look at energy downrange as well as trajectory and you might just find your answer there.

Thats actually what I'm having a hard time with. 175 grain .300WM Sierra HPBT is running an average of 2800 FPS even though it's still a .308 diameter round. I'm trying to find what a .300 will do that an actual .308 can't to justify another platform. I saw the guy who owns Sniper's Paradise say that they were pushing .300WM to 1900 yards, but I just don't see how they're hitting that without blowing chambers. I'm pretty dedicated to getting answers on this though.

I'm honestly starting to see if I want to dedicate another platform to the ELR zone that it will need to have far superior qualities, like a .338 and load heavy with a super high BC.

I'm loading the .300WM data currently to find out what the trans-sonic zone and find where it falls off the table. I'll post what I find.

[Jafar]

Someone feel free to do the math behind me, but this is what I found;

A SMK 175 gr HPBT for .300WM, at a 1000 yds will have 1361 FPS with 719 FT-LBS, going subsonic at 1200 yds.

A SMK 175 gr HPBT for .308, at a 1000 yds will have 1185 FPS with 546 FT-LBS, going subsonic at 1100 yds.

It would take some radical load development to invest in a .300WM if I already owned a .308.

[GrantA]

As much as I want to keep hoarding 30-06 brass for myself, if you're stuck between 308 and 300wm you need a 30-06.

[Tack Driver]

I'm honestly starting to see if I want to dedicate another platform to the ELR zone that it will need to have far superior qualities, like a .338 and load heavy with a super high BC.

I think you're on to something there.

[Rumbler]

I've got .408 CheyTac dies already.