.300 win mag barrel length and twist...

Well I am sure all of us have been caught out before because we did not know what we did not know! I once bought a rifle chambered in .243 and then found out I could not shoot the VLD target rounds I wanted to shoot. Latter when I looked into it more I found out that no one at the time produced a factory rifle that would handle those your only option was to build your own. A lot of factory rifles are terrible in that regard. There is no reason to be using twist rates today that do not support the VLD bullets on the market. I have always thought you should be able beat the CEO of a gun company over the head with their product when they do mind numbingly archaic things like build and sell a rifle in 308 Win with a twist or 243 Win with 1:9. It like they have an IQ bellow 83 or they are living under a rock for the past 20 years. You know they have to be retooling regularly which means they could make a change at that time and incur no additional cost above the existing cost of retooling.

I have never understood why factories do not build what we really want to buy and we all keep buying it anyways!

My first 300 Win Mag was a Browning A-Bolt with Boss. I was 1 year out of high school and away at college. I am 45 now so that was a long time ago. The heaviest bullet most where shooting was SMK 190gr. but today that is not even considered a heavy load.

https://www.americanrifleman.org/articles/2017/5/24/unsung-hero-the-mk-248-mod-1/

jpfrog said:

A 1:9" is fine but when I rebarrel my 300wm I'll be looking to go 1:8" if possible so I can shoot the big solids like the 227gr Hammer Hunters (https://hammerbullets.com/product/308-cal-227g-hammer-hunter/), but with a 1:9" you can still shoot their 199gr and 214gr offerings.

I agree with going between 26-28" on length, especially if doing the carbon barrel over the steel.

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Ditto!

I guess I dont understand all the heavy bullet craze if you say are running a 300 Win. Mag at 2950 with the 215 and you say step up to the 230 and your muzzle velocity drops to 2875 you dont gain anything, so to me if you dont keep up your MV it's a wash. I guess it you just like to experiment then so be it.
I guess my thinking is if it ain't broke dont fix it.
Now something like a 300 norma is a different story.

My 300WM has a 26" 1:10 twist with a .298 bore and it shoots 190-215 weight
bullets pretty well. I'm going this week to try some 200 ELD-X loads that should
wack a whitetail?

L.Sherm said:

I guess I dont understand all the heavy bullet craze if you say are running a 300 Win. Mag at 2950 with the 215 and you say step up to the 230 and your muzzle velocity drops to 2875 you dont gain anything, so to me if you dont keep up your MV it's a wash. I guess it you just like to experiment then so be it.
I guess my thinking is if it ain't broke dont fix it.
Now something like a 300 norma is a different story.

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Have you read the NRA Article Link on the Mk248 Mod 1? It allows you to match or outperform the 338 LM with a standard length action chambered in 300 Win Mag. It saves you weight and it saves you money by building on the existing long action Remington actions that the Army and the Navy already have on hand. Previous to this they used 190gr. SMK on the 300 Win Mag.

50 BMG, 338LM, are super heavy and expensive and standard 7,62 NATO is too under powered to take out material or to effectively kill at a safe distance consistently!

I routinely use a 30-06 and Mauser 8x57 to do everything that most would use a 338 Win Mag for. Modern powders are also opening new doors and a lot of companies and competitive shooters are doing compound loads. If you really want to not "fix what is not broken" I would expect you to think that all Ackley Improved cartridges are a fools folly! Which would put you at odd's with at least 75% of this site since they love to fix what is not broken by means of the insanely wasteful AI cartridges! By wasteful I mean the waste of barrel life fire forming cases and waste of time that the entire process incurs over just selecting a better more modern case.It only makes sense if you are sitting on a huge stockpile of old government surplus or cheap brass from long ago.

I am sure it made some sense many decades ago. In this case the Mark 248 Modification 1 makes more sense than just buying a 338LM and it is far better than anything Akley ever developed that is still with us today. It does not matter if you work the numbers from a miltary sniper stand point or from a long range hunting stand point it is not opinion it is a fact that it will do what thr far larger heavier 338's do as well or better for less money and less weight!

johnlittletree said:

Have you read the NRA Article Link on the Mk248 Mod 1? It allows you to match or outperform the 338 LM with a standard length action chambered in 300 Win Mag. It saves you weight and it saves you money by building on the existing long action Remington actions that the Army and the Navy already have on hand. Previous to this they used 190gr. SMK on the 300 Win Mag.

50 BMG, 338LM, are super heavy and expensive and standard 7,62 NATO is too under powered to take out material or to effectively kill at a safe distance consistently!

I routinely use a 30-06 and Mauser 8x57 to do everything that most would use a 338 Win Mag for. Modern powders are also opening new doors and a lot of companies and competitive shooters are doing compound loads. If you really want to not "fix what is not broken" I would expect you to think that all Ackley Improved cartridges are a fools folly! Which would put you at odd's with at least 75% of this site since they love to fix what is not broken by means of the insanely wasteful AI cartridges! By wasteful I mean the waste of barrel life fire forming cases and waste of time that the entire process incurs over just selecting a better more modern case.It only makes sense if you are sitting on a huge stockpile of old government surplus or cheap brass from long ago.

I am sure it made some sense many decades ago. In this case the Mark 248 Modification 1 makes more sense than just buying a 338LM and it is far better than anything Akley ever developed that is still with us today. It does not matter if you work the numbers from a miltary sniper stand point or from a long range hunting stand point it is not opinion it is a fact that it will do what thr far larger heavier 338's do as well or better for less money and less weight!

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I believe this is the article you are referring to.

https://www.americanrifleman.org/articles/2017/5/24/unsung-hero-the-mk-248-mod-1/

Basically it says using the more modern powders we can achieve more than satisfactory results beond 1,200yds using the heavy for caliber offerings up to 220gr by exceeding SAAMI spec for OAL loading essentially to mag length which is basically what most of us here have been dong for several years.

It essentially shows that there's very little difference betwen the .338LM and .300wm when loaded appropriately at ranges from 800-1,200yds or so.

It's hard to be H1000 for consistency but the Alliant powders showed less variation with temps.

My best results have been with RL23 and RL26 rather than RL22 but then I'm shooting longer barrels than they are with their limit being 24" which requires faster powders to achive similar velocities.

Most of that article is about improving a sniper's ability from 1200 to 1500 yards.
I'm comparing a 215 to a 230 to 1000 yards for a hunting situation. Run the numbers on Bergers calculators you will see what I refer to. Let's be honest how many of us can shoot effectively to the 1500 yard mark and consistent I doubt there's many Chris Kyle's among us me included.
All I'm saying is be honest with yourself with your capabilities, run the numbers before you jump on the band wagon about these heavier bullets if you just wanna wear out barrels and experiment then so be it.
But if you expect big gains you may be disappointed.

Another factor in a this is how many of us have a place to shoot to a 1000 yards to do any testing let alone out to 1500.

Responding to the .300 winmag vs .338 Lapua. There still is a difference in performance even if you push the .300 WinMag well beyond it's rated capabilities (as in the MK248 mod1- with a ballistically inferior bullet), by that I mean run the pressure up so high that they stop issuing that ammo. Having been issued the M2010, owning a .338 Edge & RUM and firing multiple .338 Lapua configurations (both domestic & foreign military) there is no way I would take the .300 (especially the way our ammo is) over the more long range ballistically superior .338!

L.Sherm said:

Most of that article is about improving a sniper's ability from 1200 to 1500 yards.
I'm comparing a 215 to a 230 to 1000 yards for a hunting situation. Run the numbers on Bergers calculators you will see what I refer to. Let's be honest how many of us can shoot effectively to the 1500 yard mark and consistent I doubt there's many Chris Kyle's among us me included.
All I'm saying is be honest with yourself with your capabilities, run the numbers before you jump on the band wagon about these heavier bullets if you just wanna wear out barrels and experiment then so be it.
But if you expect big gains you may be disappointed.

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You don't need to be Chris Kyle to appreciate the benefits of the 210-220gr class bullets from 600-1000yds.

WildRose said:

You don't need to be Chris Kyle to appreciate the benefits of the 210-220gr class bullets from 600-1000yds.

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I agree the 210- 215 is a perfect 300 win class bullet from 600-1000 but step up to the 230 and with the velocity drop you aren't gaining anything. All I'm saying is just because you step up to a heavier bullet with a higher B.C and you lose velocity you aren't gaining anything.
Just run the numbers if you dont believe me.
Im not trying g to start a p****** match to each his own, enough said.

WildRose said:

You don't need to be Chris Kyle to appreciate the benefits of the 210-220gr class bullets from 600-1000yds.

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I like the heavier bullets but not to where you are getting diminshing returns from it. I sure don't want to get shot with either though.

Im going with Bartlien 26" 1/9 plan to shoot 215's or 230 bergers… hopefully good.

I,m thinking of a 180 gr .224 solid bullet in a 375 weatherby case, running a 1x5 twist and a 34" barrel for 3000 yard shooting as 4500 fps.