Leupold BX-4 Rangefinding Binoculars

6.5-300 weatherby mag. Worth it or not?

Bigmo58

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So I’m seriously thinking about getting into the 6.5-300 weatherby Magnum. I’ve found myself deep into the 6.5 craze having multiple 6.5’s but only one is a creedmoor. Does anyone have the weatherby and is it worth getting into?
 
The ballistics look great on the Weatherby, but this may not be the best place to discuss calibers and cartridges. Or admit to owning a Creedmoor. Some old saying about opinions being likened to assholes comes to mind.
 
The ballistics look great on the Weatherby, but this may not be the best place to discuss calibers and cartridges. Or admit to owning a Creedmoor. Some old saying about opinions being likened to assholes comes to mind.
While that is true I was hoping for the thoughts of those who have one. And as for the creedmoor it’s great for burning ammo and improving my shooting ability. But when it comes to hunting my 6.5-284 or 6.5 prc are much better.
 
I’m getting almost 3300 FPS with a 140gr bullet from a case with roughly 61gr H2O capacity, and the 6.5-300 holds over 100gr of water. You decide if it’s worth it. There are much smaller cartridges that will get 95%+ of what that cartridge will do and they give you 2-5 times the barrel life.
 
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I just got into the 6.5 PRC this year and really like it. I'm interested in the 6.5-300, but don't have one. I've owned a couple of other Weatherby mags and liked a lot about them except when it came to buying ammo.
 
If you want to shoot laser beams, have a point blank range of close to 375/400 yards, and pay $5 a (non reloaded) cartridge, then this is the caliber for you.

127 gr @ 3531 FPS

140 gr @ 3395 FPS

I bet you could easily surpass these Wiki numbers with reloading
 
-Pick a specific bullet or two you want to deliver
-Pick an effective distance you want to deliver it at (whether it be steel, animals, whatever)
-Determine what MV you need to make that happen
-Consider component quality, costs, availability, and recoil

That will give you your answer.
 
Ammo and loading components are way to costly for the 6.5-300.
The throat erosion will be accuracy detrimental in 600 rounds or less.
That pretty well makes it a fun while it lasts cartridge, only for those with money to spare.
 
I was lucky enough to win a 26 nosler at a Mule Deer foundation banquet this summer. Not a 6.5-300, but close. I'm shooting 127 barnes LRX at 3380. With a 200 yard zero, I drop about 20" at 500. I will be able to hold on fur for pretty much anything I want to shoot out to 400. I only expect to get 500 rounds out of the barrel. I am going to use it for hunting and not targets, so it should last me the rest of my life. I settled for a 1/2 MOA load and maybe could've done better or gotten a tighter group with more velocity, but am keeping barrel life in mind so I didn't tweak it. I'll let you know how it does on antelope in a couple of weeks.
 
Around 63-67gr of H20 capacity will max out a 6.5mm bore with a 24”-26” barrel. More powder than that just wears your barrel out faster without pushing bullets any faster. Higher pressures(like magnums and newer cartridges) will allow you to continue gaining velocity toward the top end of that range, while more normal pressures, or low pressures(like Mauser cartridges) will stop improving in velocity at the low end of that range. Water weighs more than powder. An H2O capacity of 67gr will have powder charges much lighter than that. If you look at load data you’ll see that in “normal “ cartridges they usually get data with 22”-24” barrels while with “hot rods”, they test with 26”-28” barrels. Small cartridges for their bore often gain or lose around 20-25fps per inch, while cartridges that are large for their bore diameter can gain or lose 40-50fps per inch. If you’re not gonna carry a really long barrel, you’re not gonna benefit much if any from the big cartridges. Look at some reloading data and see how long the barrel they used was. Nosler uses a 28” barrel to test loads in the 26 Nosler. If you’re not going to carry a barrel that long, you won’t get as much benefit from a huge cartridge. When you shorten a barrel on a 6.5-284 you lose a lot less velocity than when you shorten it on a 6.5-300. When the published velocities from a 6.5-284 come from a 24” barrel and from a 26 Nosler come from a 28” barrel, and you only want to carry a 24” how much better is the 26 Nosler really?

I’m shooting 140gr bullets at 3300fps(actually it’s more accurate at 3175) with 51.2gr of RL-33 using a 30” barrel. A .26 Nosler uses over 90gr of powder to push a 140gr bullet at 3300fps from a 28” barrel. A .26 Nosler has an accurate barrel life around 700rnds. Mine should last 1500-2000rnds.

I’d recommend a 6.5-06 or 6.5-06 AI if you’re a handloader. If you really need to buy ammo off the shelf, the 6.5PRC is a good bet, so is the 6.5-284. If you handload and use a normal length barrel you’ll likely end up within 100-200fps of a 6.5-300 with a short barrel. You gotta have a long barrel to get those velocities. If you’re willing to carry a 30” barrel, use half your barrel life during load development, and wanna practice with something else so that your hunting gun will last a while, then the 6.5-300 will probably reach 3400+ with a 140 from that barrel length and be the fastest shooting big game cartridge you ever own.
 
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Go for it. It is not about barrel life or burning less powder It's about having fun and playing with new rifles and rounds.:D
This. If you are not bothered by the so called disadvantages, who cares what others think? If I would have listened to the naysayers, I would have missed out on shooting RUMS for 20 years. mtmuley
 
The ballistics look great on the Weatherby, but this may not be the best place to discuss calibers and cartridges. Or admit to owning a Creedmoor. Some old saying about opinions being likened to assholes comes to mind.
Make you a heck of a deal on one!!
 
If I was into velocity, that would be enough for me to get one. Imagine laying on your death bed and moaning the fact you never had one. Want to try one? Get one and then you'll know for sure.
 
Around 63-67gr of H20 capacity will max out a 6.5mm bore with a 24”-26” barrel. More powder than that just wears your barrel out faster without pushing bullets any faster. Higher pressures(like magnums and newer cartridges) will allow you to continue gaining velocity toward the top end of that range, while more normal pressures, or low pressures(like Mauser cartridges) will stop improving in velocity at the low end of that range. Water weighs more than powder. An H2O capacity of 67gr will have powder charges much lighter than that. If you look at load data you’ll see that in “normal “ cartridges they usually get data with 22”-24” barrels while with “hot rods”, they test with 26”-28” barrels. Small cartridges for their bore often gain or lose around 20-25fps per inch, while cartridges that are large for their bore diameter can gain or lose 40-50fps per inch. If you’re not gonna carry a really long barrel, you’re not gonna benefit much if any from the big cartridges. Look at some reloading data and see how long the barrel they used was. Nosler uses a 28” barrel to test loads in the 26 Nosler. If you’re not going to carry a barrel that long, you won’t get as much benefit from a huge cartridge. When you shorten a barrel on a 6.5-284 you lose a lot less velocity than when you shorten it on a 6.5-300. When the published velocities from a 6.5-284 come from a 24” barrel and from a 26 Nosler come from a 28” barrel, and you only want to carry a 24” how much better is the 26 Nosler really?

I’m shooting 140gr bullets at 3300fps(actually it’s more accurate at 3175) with 51.2gr of RL-33 using a 30” barrel. A .26 Nosler uses over 90gr of powder to push a 140gr bullet at 3300fps from a 28” barrel. A .26 Nosler has an accurate barrel life around 700rnds. Mine should last 1500-2000rnds.

I’d recommend a 6.5-06 or 6.5-06 AI if you’re a handloader. If you really need to buy ammo off the shelf, the 6.5PRC is a good bet, so is the 6.5-284. If you handload and use a normal length barrel you’ll likely end up within 100-200fps of a 6.5-300 with a short barrel. You gotta have a long barrel to get those velocities. If you’re willing to carry a 30” barrel, use half your barrel life during load development, and wanna practice with something else so that your hunting gun will last a while, then the 6.5-300 will probably reach 3400+ with a 140 from that barrel length and be the fastest shooting big game cartridge you ever own.

If you keep barrel length the same does velocity scale? I have a .264 win mag with a 24 inch barrel and shooting a 140 grain bullet, I haven't gotten much more than 3050fps, although I've never loaded into the danger zone where I'm noticing pressure signs. If I tossed on a 30 inch barrel, I would likely be able to best 3300fps correct? Similarly, a 6.5-300 with a 36 inch barrel is going to be faster than 3400?

I don't feel like I have a good understanding of how case geometry effects velocity versus pure volume of powder versus barrel length, etc.
 

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Shorter barrel life is dumbest argument in the history of all arguments since the beginning of time. Barrels aren’t really that expensive. It’s like saying nobody should buy a fast car because they wear tires out fast. Well I guess I better just stick to a minivan. Good old reliable minivan.
 
If you keep barrel length the same does velocity scale? I have a .264 win mag with a 24 inch barrel and shooting a 140 grain bullet, I haven't gotten much more than 3050fps, although I've never loaded into the danger zone where I'm noticing pressure signs. If I tossed on a 30 inch barrel, I would likely be able to best 3300fps correct? Similarly, a 6.5-300 with a 36 inch barrel is going to be faster than 3400?

I don't feel like I have a good understanding of how case geometry effects velocity versus pure volume of powder versus barrel length, etc.

Assuming equal bullet weight, velocity will scale directly with the work done on the bullet until the bullet reaches the maximum velocity that the gasses could expand in the absence of a bullet. The bore area multiplied by the average pressure multiplied by the length will give you work. A*P*L. Friction is a force just like pressure, and it does work on the bullet in the opposite direction. It increases linearly and is directly related to velocity. The work done against us by friction will be the average friction multiplied by the barrel length. Average pressure is going to be very very close to peak pressure plus the pressure when the bullet exits the muzzle, divided by two. So, we can increase work do on the bullet in various ways. Increasing bore diameter is easy and efficient(keeping the average pressure the same in a bigger bore will require more powder). Sticking to a 6.5mm bore, we can only increase average pressure and barrel length. To increase average pressure we can’t do much with peak pressure. Cartridge brass won’t handle much more than 70,000psi. That leaves us trying to raise the pressure when the bullet leaves the muzzle. This is done by adding more powder, but lowering the burn rate so that peak pressure remains the same, but gas volume, and the thus final pressure, goes up. The closer you get final pressure to peak pressure, the less room there is for improvement. Progressive burn powders allow peak pressure to be maintained longer and requires more of an incremental approach to measure average pressure, but the principle remains the same. The last variable is barrel length. Lengthening the distance over which the force is applied also increases the work done on the bullet, and thus the velocity(until velocity is high enough that friction equals or exceeds the the force applied by the gasses behind the bullet) the interesting thing about increasing barrel length is that not only does allow you to do more with the gasses you have, but it allows you to make use of more gases. If you fire the same load in a 24” and 26” barrel, the longer barrel will have a lower final pressure, but more work was done on the bullet because over the first 24” the pressure was the same in both barrels, the final 2” was a bonus. As mentioned before, the final pressure is lower in the 26” barrel, so now we can take advantage of additional powder.

The slightly shorter answer. Due to the variable effecting velocity, small cartridges for their bore diameter generally only benefit slightly from increased barrel length. As cartridge volume increases and barrel length remains the same, we reach a point of diminished returns such that any increased velocity is essentially meaningless, but increasing barrel length can allow us to take advantage of those larger cartridges. For a 6.5mm bore, the 6.5 Rem Mag, 6.5x55AI, 6.5-284 and 6.5-06 are very near the pinnacle of performance for normal hunting barrel lengths, and although the larger cartridges will show VERY MINOR velocity increases the come at a high cost. Increasing barrel length will increase velocity of the cartridges named in the 25-35fps range depending on which one is used and(6.5 Rem Mag holds about 60gr H2O, 6.5-06 holds almost 67gr, more powder means more increase per inch) and the initial barrel length.(going from 22”-24” will show a larger increase than going from 24”-26”). Big 6.5 magnums can get in excess of a 50fps increase per inch. You would likely exceed 3350fps if you went to a 30” barrel. One last consideration however is that friction increases with velocity, and thus the improvement in velocity from increased barrel length will be smaller with light bullets at extreme velocity than with heavy bullets at more moderate velocity.

I guess that was longer. Maybe the second part simpler.
 
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Shorter barrel life is dumbest argument in the history of all arguments since the beginning of time. Barrels aren’t really that expensive. It’s like saying nobody should buy a fast car because they wear tires out fast. Well I guess I better just stick to a minivan. Good old reliable minivan.

Let’s see, $360ish bucks for a custom blank, 1/4 of my $200 reamer’s life, $200-$400 for the work for a good smith, 2-6month wait for the blank to arrive 2-6month wait at the smith...barrels are expensive. I’d much rather have a barrel that lasts 1500+ rounds than 600. I could spend 100+ rounds in load development, sight-in, deciding to change bullets, etc. Barrel life may not be the primary factor is choosing a cartridge, but it probably should play some role for a high percentage of people. If you want to hunt with a gun that’s only good for 600 shots, then you at least need to understand it and practice with very similar setup chambered for something more moderate. If you have a lot of guns and want to play with a hot rod, be my guest. Someone who asks “is it worth it?” Is already showing at least some concern regarding disadvantages, so it’s good for them to know what the disadvantages are, and what the real world advantages are.(If you’re going to carry a 22” barrel, don’t use data generated in a 28” barrel for comparison, similar issues with handloads etc.)

The 6.5-284 died in F-Class primarily because it lasted for 800-1200rnds and having to re-barrel in the middle of a season, or worse yet, near the end was way too risky.
 
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