18-20" 300 RUM: change my mind..

[7.62 Gunner]

If you wanna do it just do it! Doesn't matter what we think! But do share the results with us!!!!

Ps I think that sounds bada** and share your lack of concern with efficiency and practicality. People talk barrel life and efficiency…so go shoot a .308 and convince yourself that the Chevy Cruze is an exhilarating ride . And I can't stand how when someone suggests an 18 inch 30 mag of some kind right away people are just like "pointless, no better than a 30-06". A 26 inch 30-06 MAYBE…out of a much handier rifle. Practicality and efficiency can go fly a kite, we want PERFORMANCE!!!!! Step on the gas, FLOOR IT!!!!!!!!

After chasing the "efficient" magnums around for years, and blowing primers trying to make them perform like their bigger counter parts I'm in total agreement with you.
Just ordered a 20" 300 RUM McGowen prefit for my anTi

 

[Tidus56]

After chasing the "efficient" magnums around for years, and blowing primers trying to make them perform like their bigger counter parts I'm in total agreement with you.
Just ordered a 20" 300 RUM McGowen prefit for my anTi

What contours are you ordering these shorties in?

 

[7.62 Gunner]

Love The Short Barrels!
230 Berger with 90.4 grains of Retumbo , Fed Mag Primer, 4.04 OAL, 18" barrel 2825 fps

Yeah I appreciate the input, your results originally got me thinking about a shorty RUM. I might call it the "Half Pint"

 

[7.62 Gunner]

What contours are you ordering these shorties in?

I asked for the lightest contour that gives me .730 at the muzzle, I think it'll be a #4.
My 18" mcGowen 7-300 wsm improved has a factory tikka contour with a flared up muzzle.
I really like that option for an ultralight, but with a RUM I like a heavier barrel

 

[Chas1]

Just how long is your suppressor ? Going from 24 to 20" I don't think it'll be that big a deal. Try it and see.

 

[jasonprox700]

They will also say you need very fast burning powders and light weight bullets for short barrels.

I have found that even in short barrels- a faster burning powder seems to pressure out before you reach max muzzle velocities compared to "normal" powders for cartridges-- why wouldn't it? Your max pressure is reached in the first few inches of barrel --- for example in the 308 I tried quite a few "faster" powders but my best accuracy/speed combo ended up being with varget. -- and the 300wsm likes rl 23 or 26 even though it has a short barrel.

AMEN!!!

I read that all the time about running "Fast" powders in a short barrel. Those same people stating that don't have a clue about powder burn rates and how long it actually takes powder to actually burn from a solid state to a gas.

Whatever powder gives you the best velocity in say a 20-24" barrel will still give you the best velocity in a 16" barrel. I've tried this on a handful of cartridges (no "magnums" though) and the results are always the same. The only time a burn rate plays in to the equation is barrel harmonics (finding that "node") and trying to make an auto loader cycle (AR's).

 

[jbur13]

300 RUM, 22" barrel with 1 in 8 twist. running the ultra 7 thunderbeast.
220eldx @ 3077fps. 10lbs with suppressor

 

[Ernie]

I don't think that most people can imagine how much grief people threw my way, back in the 80s and the 90s (even early 2000) about Short Barrels and Big Cartridges, that cartridge is Not Efficient, or I kept being told I need to use Faster powders, it won't have accuracy, etc…Add to that LR Shooting and LR Hunting
I love threads like these!
I am Happy To Enable!!!

 

[Ernie]

Yeah I appreciate the input, your results originally got me thinking about a shorty RUM. I might call it the "Half Pint"

Love It!

 

[7.62 Gunner]

Just how long is your suppressor ? Going from 24 to 20" I don't think it'll be that big a deal. Try it and see.

It's 8.4" and DT so it adds about 8" overall

300 RUM, 22" barrel with 1 in 8 twist. running the ultra 7 thunderbeast.
220eldx @ 3077fps. 10lbs with suppressor
View attachment 399017

That's a sweet setup, what powder and OAL ?

 

[7.62 Gunner]

I don't think that most people can imagine how much grief people threw my way, back in the 80s and the 90s (even early 2000) about Short Barrels and Big Cartridges, that cartridge is Not Efficient, or I kept being told I need to use Faster powders, it won't have accuracy, etc…Add to that LR Shooting and LR Hunting
I love threads like these!
I am Happy To Enable!!!

Yeah I can only imagine! I know it took me awhile to change my ways..
I was a 26" minimum kinda guy forever, I hate brakes for hunting and finally took the plunge a few years ago and chopped my 6.5 saum to 16" and got a suppressor.

Your 18" RUM would get a guy to 1100 yards for elk, try saying that 15 years ago..

 

[MSURunner]

GRT models H1000, 225 ELDM @ 3.850 and a 20" barrel to top out at about 2700 fps before going overpressure. You could probably step it up a bit from there, but you might be pushing it a bit hard to get to your 2800 fps number. FWIW, it models a 300 WM to reach the same velocity at 24", so sticking with the RUM gets your 4" of length savings at the expense of about 15 gn of extra powder.

 

[jbronner13]

I don't know the numbers you are looking to achieve but wasn't the 300 RCM specifically designed for short barrel work? I am by no means a cartridge or handloading expert and will never claim to be so if someone with more experience wants to weigh in?

 

[beretzs]

300 RUM, 22" barrel with 1 in 8 twist. running the ultra 7 thunderbeast.
220eldx @ 3077fps. 10lbs with suppressor
View attachment 399017

Great looking rig!