300 wby vs 300 win mag
- Thread starter LRH ELKAHOLIC
- Start date
Help Support Long Range Hunting Forum
and ya, we all know that longer freebore/seating depth gains a bit of capacity, a bunch of guys here have done that since this forum was established, I've done that with multiple cases and have never seen more than 2 gr improvement in capacity and little velocity increase, unless you combine that with enlarging the top of case body and pushing the shoulder up for a shorter neck, THEN you will gain 5-10 gr capacity improvement, depending on the taper & neck length of the parent case.
the 300 Win Mag IS already improved in that manner over the 264, 7mm & 338 mags, along with a longer case length which helps it gain the capacity, kind of like the 300 Wby uses length to gain precious fuel space over the 300 Win Mag
simply shoving bullet out without any other improvements and claiming superiority is ridiculous and you need to be aware of the crew here on this forum who are very well versed in such things
....
did this one about 6-7 years ago
...with all the Imps, I got to 111 gr h20 capacity, a solid increase over the parent 300 Norma
a handful of us here expirimented with this years ago & now everybody is doing it ...
sadly the 300 NM Imp has become a "manbun" cartridge, lol
...
the 300 Win Mag IS already improved in that manner over the 264, 7mm & 338 mags, along with a longer case length which helps it gain the capacity, kind of like the 300 Wby uses length to gain precious fuel space over the 300 Win Mag
simply shoving bullet out without any other improvements and claiming superiority is ridiculous and you need to be aware of the crew here on this forum who are very well versed in such things
....
did this one about 6-7 years ago
...with all the Imps, I got to 111 gr h20 capacity, a solid increase over the parent 300 Norma
a handful of us here expirimented with this years ago & now everybody is doing it ...
sadly the 300 NM Imp has become a "manbun" cartridge, lol
...
Last edited:
Hugnot
Well-Known Member
just goin along with my gear down & looks like I hooked onto something real big - is a 300 LRH a .338 Norma necked down to .308?
This thread is about comparisons between the .300 WM & .300 WBY. Any observations of cartridge that is loaded with 95-97 grains of powder - "my 300 LRH runs at 3225-3250 fps comfortably with 225 -230 gr bullets" are irrelevant to the thread.
What I read "you're comparing an improved wildcat 300 Win Mag chamber to a factory standard 300 Wby ... with same components, well cowgirl.... two different cartridges that will load up differently" Yes, the 3.6 COAL .300 WM will "load up differently" than the 3.34 COAL .300 WM and provide somewhat higher velocities, closing the gap for the .300 WBY. The only difference is that my 3.6 COAL chamber has a longer throat or leade to accept longer bullets without reducing powder capacity. Factory .300 WM ammo will work in my chamber without changing brass dimensions like shoulder angle or datum length when head spaced on shoulder.
Possibly a new thread might be made on the virtues of the .300 LRH so we could learn more. Hopefully, this thread will be more objective and omit numerous confrontational statements.
I think this has some value:
Bring it on chief,.
Last edited:
This has become a wildly entertaining early morning dump! 
So far we've had "300 wby isn't an accurate cartridge" (because of 'slop'?!), "150 fps makes no difference" (then why not shoot a 30-06? 308? 30 carbine?!), and "300 WM is just as fast as 300 wby if you load it right", case capacities and accurate comparisons be damned! Anybody care to go for the cliche superfecta and throw "efficiency" in there?
So far we've had "300 wby isn't an accurate cartridge" (because of 'slop'?!), "150 fps makes no difference" (then why not shoot a 30-06? 308? 30 carbine?!), and "300 WM is just as fast as 300 wby if you load it right", case capacities and accurate comparisons be damned! Anybody care to go for the cliche superfecta and throw "efficiency" in there?Also, Swamplord with the quote of the month. Thanks for the laughs and attempting to maintain a level of sanity on this post!
Hugnot
Well-Known Member
Calculations to determine how much more Retumbo powder could be poured into my 3.6 COAL .300 WM with a 200 H ELDM.
Bullet volume 3.6 COAL in case = .16 CC - lower part of boat tail (truncated cone) measured at junction of body & shoulder
Bullet volume 3.34 COAL in case = .59 CC - volume .230 height, .308 diameter cylinder plus volume of boat tail, measured down from junction of body & shoulder.
Difference = .59 - .16 = .43 CC's
VMD, Volume 1 grain Retumbo in CC's = .0721 CC's
.43 CC's / .0721 = 5.96 grains or so, on my simple powder measure 6.0 grains. 6/78 = would provide another 7.6 % powder capacity over the maximum Retumbo load in the Hodgdon load site.
Extending the COAL to 3.6 inches is a sane & efficient way to boost the "efficiency" of the .300 WM to enable it to favorably compare with the .300 WBY. accurate comparisons here
Then....
and ya, we all know that longer freebore/seating depth gains a bit of capacity, a bunch of guys here have done that since this forum was established, I've done that with multiple cases and have never seen more than 2 gr improvement in capacity and little velocity increase, unless you combine that with enlarging the top of case body and pushing the shoulder up for a shorter neck, THEN you will gain 5-10 gr capacity improvement, depending on the taper & neck length of the parent case.
anecdotal stuff is funny (not necessarily true or reliable, because based on personal accounts rather than facts or research)
Then...
Bullet volume 3.6 COAL in case = .16 CC - lower part of boat tail (truncated cone) measured at junction of body & shoulder
Bullet volume 3.34 COAL in case = .59 CC - volume .230 height, .308 diameter cylinder plus volume of boat tail, measured down from junction of body & shoulder.
Difference = .59 - .16 = .43 CC's
VMD, Volume 1 grain Retumbo in CC's = .0721 CC's
.43 CC's / .0721 = 5.96 grains or so, on my simple powder measure 6.0 grains. 6/78 = would provide another 7.6 % powder capacity over the maximum Retumbo load in the Hodgdon load site.
Extending the COAL to 3.6 inches is a sane & efficient way to boost the "efficiency" of the .300 WM to enable it to favorably compare with the .300 WBY. accurate comparisons here
Then....
and ya, we all know that longer freebore/seating depth gains a bit of capacity, a bunch of guys here have done that since this forum was established, I've done that with multiple cases and have never seen more than 2 gr improvement in capacity and little velocity increase, unless you combine that with enlarging the top of case body and pushing the shoulder up for a shorter neck, THEN you will gain 5-10 gr capacity improvement, depending on the taper & neck length of the parent case.
anecdotal stuff is funny (not necessarily true or reliable, because based on personal accounts rather than facts or research)
Then...
Hugnot
Well-Known Member
Thanks all for going thru this stuff. My purpose was to present the somewhat handicapped .300 WM in a better light in comparison with the .300 WBY by showing a extension of COAL would help things out for the .300WM.
"The primary effect of loading a cartridge long is that it leaves more internal volume inside the cartridge. This extra internal volume has a well-known effect; for a given powder charge, there will be less pressure and less velocity produced because of the extra empty space. Another way to look at this is you have to use more powder to achieve the same pressure and velocity when the bullet is seated out long. In fact, the extra powder you can add to a cartridge with the bullet seated long will allow you to achieve greater velocity at the same pressure than a cartridge with a bullet seated short."
This is from:
COAL.pdf (bergerbullets.com) not me
Some nice photos:
The H1000 charge difference is 5.5 grains more for the 3.6" .300WM (76.5) than the shorty, capacity challenged 3.34WM (71.0).
My calculations came in just under 6 grains using VMD data for Retumbo. Retumbo VMD = .0720, H1000 VMD = .0713, H1000 is somewhat lighter per equal volume & that might account for some of the nearly .5 grain difference (needs more work, like more accurate measurements). In the works is a spread sheet to estimate case volume reduction using bullet displacement. Measuring the minor & major diameters of the boat tail (truncated cone) is not very exact due the radius on the bottom of the boat tail.
VMD info:
Just ask your friendly gun smith to ream the chamber with a longer throat. No other changes - provide a dummy round with the bullet of your choice. Also in the works is a Rem 700, having a 28 ", 10 twist, light Palma barrel, single shot - no magazine COAL restrictions, receiver face squared & lugs lapped in. .
Today at the range I got around 2885 - 2914 fps, using 74 gr. IMR 7977 with the old 208 Hornady AMax bullet from the nearly 50 YO, 3.60, .300 WM.
Another fyne cartridge, somewhat handicapped but having extensive accessibility, thus excluded from most complaint avenues, is the 2-fo-3 (.243 W). SAAMI standards specify a COAL of 2.710, my .243W is loaded with a COAL of 2.810. It does nicely with the Barnes 95 LR bullet for shooting deers.
This thread has been lots of fun!
"The primary effect of loading a cartridge long is that it leaves more internal volume inside the cartridge. This extra internal volume has a well-known effect; for a given powder charge, there will be less pressure and less velocity produced because of the extra empty space. Another way to look at this is you have to use more powder to achieve the same pressure and velocity when the bullet is seated out long. In fact, the extra powder you can add to a cartridge with the bullet seated long will allow you to achieve greater velocity at the same pressure than a cartridge with a bullet seated short."
This is from:
COAL.pdf (bergerbullets.com) not me
Some nice photos:
The H1000 charge difference is 5.5 grains more for the 3.6" .300WM (76.5) than the shorty, capacity challenged 3.34WM (71.0).
My calculations came in just under 6 grains using VMD data for Retumbo. Retumbo VMD = .0720, H1000 VMD = .0713, H1000 is somewhat lighter per equal volume & that might account for some of the nearly .5 grain difference (needs more work, like more accurate measurements). In the works is a spread sheet to estimate case volume reduction using bullet displacement. Measuring the minor & major diameters of the boat tail (truncated cone) is not very exact due the radius on the bottom of the boat tail.
VMD info:
Just ask your friendly gun smith to ream the chamber with a longer throat. No other changes - provide a dummy round with the bullet of your choice. Also in the works is a Rem 700, having a 28 ", 10 twist, light Palma barrel, single shot - no magazine COAL restrictions, receiver face squared & lugs lapped in. .
Today at the range I got around 2885 - 2914 fps, using 74 gr. IMR 7977 with the old 208 Hornady AMax bullet from the nearly 50 YO, 3.60, .300 WM.
Another fyne cartridge, somewhat handicapped but having extensive accessibility, thus excluded from most complaint avenues, is the 2-fo-3 (.243 W). SAAMI standards specify a COAL of 2.710, my .243W is loaded with a COAL of 2.810. It does nicely with the Barnes 95 LR bullet for shooting deers.
This thread has been lots of fun!
Still makes me laugh! Comparing a wildcat to a factory round!
Wildcat cartridges, sometimes referred to as simply "wildcats," are custom-designed cartridges – meaning they are not mass produced, but instead made by individual shooters. The purpose of a wildcat is the cultivation of some attribute not sufficiently present in a commercially available round. Wildcats aren't great for law enforcement or military purposes, but they are great for hardcore shooting aficionados, handloaders looking to take things to the next level, and gunsmiths who want to homebrew ammunition for their homebrew weapons.
motrapper
Well-Known Member
WIW My factory RPR 300 win mag with a factory 3.84 magazine lets me seat to 3.551 with the 200 ELDX and off the lands of .025
For a Factory rifle
This was my first attempt at seating depths so I could go longer but I am getting <.5 MOA at 200yds
For a Factory rifle
This was my first attempt at seating depths so I could go longer but I am getting <.5 MOA at 200yds
skywag
Active Member
Toss them both and go 300 Super. Fireformed from 300 WBY. Here's one from JK Cloward
JK Cloward 300 Super
JK Cloward 300 Super
Last edited:
Wolf76
Well-Known Member
Against my better judgment...I thought I'd jump in on this discussion.
There are a few points that aren't open for debate like more case capacity has a higher velocity potential ---- keeping important variables constant. With regards to this, the 300 Wby wins. In same regards, the 300 wm gains velocity by having a longer throat, which allows more usable powder capacity.
The comparison of the 2 cartridges is like a 3/4 ton truck vs a 1 ton truck.
Really, after we accept a few basic principles, its all personal preference.
I love powder capacity and don't care for the massive bullet jump with weatherby cartridges. Also don't care for the double radius shoulder, but that's all personal preference. Bottom line....weatherby wins the velocity contest, just like the 1 ton truck wins the pulling weight contest.
Do the difference(s) equal to anything meaningful? Answer is all circumstance /perspective based.
In my world...if I need more than a 308W, I don't grab a 30.06 because there isn't enough difference. I think the same way about 300wm + 300 wby.
I'm very thankful for the veterans who protect our freedoms which allow us to have these important discussions
There are a few points that aren't open for debate like more case capacity has a higher velocity potential ---- keeping important variables constant. With regards to this, the 300 Wby wins. In same regards, the 300 wm gains velocity by having a longer throat, which allows more usable powder capacity.
The comparison of the 2 cartridges is like a 3/4 ton truck vs a 1 ton truck.
Really, after we accept a few basic principles, its all personal preference.
I love powder capacity and don't care for the massive bullet jump with weatherby cartridges. Also don't care for the double radius shoulder, but that's all personal preference. Bottom line....weatherby wins the velocity contest, just like the 1 ton truck wins the pulling weight contest.
Do the difference(s) equal to anything meaningful? Answer is all circumstance /perspective based.
In my world...if I need more than a 308W, I don't grab a 30.06 because there isn't enough difference. I think the same way about 300wm + 300 wby.
I'm very thankful for the veterans who protect our freedoms which allow us to have these important discussions
OK, I will play. I have three .300 WMs with different COALs. All of which is greater than reloading manual/SAAMI specs - 3.53" to 3.62". I do not have a .300 WBTY but I have a .30 LARA wildcat that I can shoot a factory .300 WBTY or .300 Jarrett factory ammo - COAL is also greater than .300 WBTY's. SAAMI spec is simply a guide to establish a standard to base upon. The key is for the "NUT" trigger to know what they are doing, SAAMI or not, when reloading. There is no substitute for safety. SAFETY, SAFETY, SAFETY...
L-R: .300 WM, .300 WBTY, .30 LARA
L-R: .300 WM, .300 WBTY, .30 LARA
Last edited:
Hugnot
Well-Known Member
In communist China gun possession is not encouraged, making some exceptions for established Olympic quality competitive shooters. Any debate related to either .300 WBY or .300 WM might be regarded in the same light as the merits of plasma type weapons to flintlock rifles by the authoritarian government - like both are regarded as menaces to established order and carefully molded thinking (neuroplasticity).
No doubt, the skillfully promoted & feted .300 WBY will never equal the velocity potential of the utilitarian .300 WM that was designed to fit into zillions of receivers having magazine lengths of a maximum 3.34 inches - like design a round that provides increased performance that will fit an established manufacturing process. SAMMI accepted the voluntary submission of max 3.34 COAL and 1000's of LGS had .300 WM ammo loaded to fit 3.34 max length magazines. Roy Weatherby designed the .300 WBY without common "06" magazine length restrictions; I can load standard .300 WM brass to make ammo without magazine length restrictions. A longer COAL does not make a wildcat.
What I think:
"The primary effect of loading a cartridge long is that it leaves more internal volume inside the cartridge. This extra internal volume has a well-known effect; for a given powder charge, there will be less pressure and less velocity produced because of the extra empty space. Another way to look at this is you have to use more powder to achieve the same pressure and velocity when the bullet is seated out long. In fact, the extra powder you can add to a cartridge with the bullet seated long will allow you to achieve greater velocity at the same pressure than a cartridge with a bullet seated short."
No doubt, the skillfully promoted & feted .300 WBY will never equal the velocity potential of the utilitarian .300 WM that was designed to fit into zillions of receivers having magazine lengths of a maximum 3.34 inches - like design a round that provides increased performance that will fit an established manufacturing process. SAMMI accepted the voluntary submission of max 3.34 COAL and 1000's of LGS had .300 WM ammo loaded to fit 3.34 max length magazines. Roy Weatherby designed the .300 WBY without common "06" magazine length restrictions; I can load standard .300 WM brass to make ammo without magazine length restrictions. A longer COAL does not make a wildcat.
What I think:
"The primary effect of loading a cartridge long is that it leaves more internal volume inside the cartridge. This extra internal volume has a well-known effect; for a given powder charge, there will be less pressure and less velocity produced because of the extra empty space. Another way to look at this is you have to use more powder to achieve the same pressure and velocity when the bullet is seated out long. In fact, the extra powder you can add to a cartridge with the bullet seated long will allow you to achieve greater velocity at the same pressure than a cartridge with a bullet seated short."
