.338 Win Mag 250 or 300 SMK

benchracer

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Can the .338 Win Mag push the 300gr SMK fast enough to offer an advantage over the 250gr SMK?

If loaded to greater than standard COAL, about what velocity could I expect to achieve with the 300gr SMK from a .338 Win Mag?

I am also looking to experiment with the Lapua Scenar bullets in both 250gr and 300gr. Has anyone tried these? How do they perform relative to the Sierra offerings?

The prospect of a new .338 Berger VLD has my interest as well. Hmmmm...
 
Load them as long as you want, you'll be lucky to push the 250 gr faster than 2600 fps out of a factory length barrel. Do your calculations from there for the 300 gr.

Simply put, the .338 Win Mag is better suited with bullets less than 250 grain.
 
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I have a338-378 wby,have you or anybody else ever shot an elk with the 300 smk? If so,how did they perform, or,would you even use these bullets for hunting elk?
 
I have a338-378 wby,have you or anybody else ever shot an elk with the 300 smk? If so,how did they perform, or,would you even use these bullets for hunting elk?

Sir:

This thread is about the 250 and 300 gr SMK and the .338 Win Mag.

Either start another thread or do a search about the 300 SMK's performance on game. There's plenty to read.
 
In my opinion the 338 win mag is best suited with the lighter bullets such as the 225 Nosler AB which has about the best BC in the 200-225 grain bullet range. It will shoot the heavy bullets accurately but within the optimum effective range of the 338 win mag I think you are best with the faster lighter bullets.

The 300 grain SMK will kill stuff just fine out of your 338-378 wby at any range you can hit it.
 
Stick to the lower weight---250 SMK is too much for the little guy. One reason I use several 338 Lapua "improved" rifles.
 
Then there are the guys who sing the praises of the .338 Whisper....

When you are launching a .800 Ballistic Coefficient bullet does the velocity really matter all that much?
When a 300gr bullet with thick target jacketing impacts living tissue at anything near 1000 fps, the blow is almost sure to be a mortal one.

Question is, do you have the twist rate to stabilize the 300gr bullet? If so, go for it. Otherwise, why not shoot a .30-06 with 200gr matchking and get the superior performance of a higher BC bullet?
 
I have shot the 300 grain SMK out of a .338WM and killed 8 feral goats to test them. The range was under 100 yards. Velocity at muzzle was 2434 fps and although they killed the goats, they were not spectacular kill. I must say that goats are not that solid an animal to test bullets on so they might work better on a more solid animal where they have more resistance and can expand.

With the 250 grain SMK I heard that they were a bit hard so I opted to try the Hornady BTHP Match projectile, instead as they have a higher B.C. anyway.

Results with these bullets was spectacular on over 100 feral goats at a muzzle velocity of 2730 fps from a Sako 24.5 inch barrel. Range was out to 495 yards.

I also shot a couple of large Sambar stags with this bullet DRT at close range, but I also lost one with a solid hit on the shoulder at 527 yards. (Dropped and rolled down the hill 15m, then go up and ran off on three legs, never to be seen again).

Have since dropped the MV of this load back to 2650 fps to maintain case life.

Anyway, these are the results that I have got with these two particular LR type bullets. Hope it helps.
 
I am going to preface my remarks by saying that I have put about 500 rounds through my .338 and have never really kept much in the way of shooting/reloading data and have never chronoed any of the factory or handloads that I have fired through it. So, at this point, anything I have to say about its performance is either subjective or solely based on theory rather than actual practice.

In short, my quest to develop long range shooting skill and knowledge is still in its infancy.


Load them as long as you want, you'll be lucky to push the 250 gr faster than 2600 fps out of a factory length barrel. Do your calculations from there for the 300 gr.

Simply put, the .338 Win Mag is better suited with bullets less than 250 grain
.

In my opinion the 338 win mag is best suited with the lighter bullets such as the 225 Nosler AB which has about the best BC in the 200-225 grain bullet range. It will shoot the heavy bullets accurately but within the optimum effective range of the 338 win mag I think you are best with the faster lighter bullets.

Stick to the lower weight---250 SMK is too much for the little guy. One reason I use several 338 Lapua "improved" rifles

I consider these remarks to be of interest because they run contrary to my own thoughts on the subject.

I have seen quite a lot of book data showing the humble .338WM pushing 250gr bullets up to and beyond 2700fps. Though I have done load development with 250gr SGK's, I did not chrono the loads so I don't really know what kind of velocity I was getting.

At this point, I totally disagree with the assertion that the .338WM is better suited to bullets in the 200-225gr range. The cartridge was designed with 250gr bullets as the "gold standard" load. In fact, I have always seen the .338WM as a pretty pointless cartridge with light bullets. Afterall, if you back the bullet weight down, the .338WM's performance can be pretty easily bettered by the .300WM and the 30-06 is not far behind.

However, given the listed BC for the 225gr Accubond, it could prove to be an exception.



When you are launching a .800 Ballistic Coefficient bullet does the velocity really matter all that much?

That is precisely the question that I am seeking to answer. Absent a reloading program and/or real world long range data, I don't know.


When a 300gr bullet with thick target jacketing impacts living tissue at anything near 1000 fps, the blow is almost sure to be a mortal one.
Question is, do you have the twist rate to stabilize the 300gr bullet? If so, go for it. Otherwise, why not shoot a .30-06 with 200gr matchking and get the superior performance of a higher BC bullet?

My rifle has a 1-10 twist, so it should be able to stabilize the 300gr bullets with no problem.

Your point on the 30-06 is well taken.



I have shot the 300 grain SMK out of a .338WM and killed 8 feral goats to test them. The range was under 100 yards. Velocity at muzzle was 2434 fps and although they killed the goats, they were not spectacular kill. I must say that goats are not that solid an animal to test bullets on so they might work better on a more solid animal where they have more resistance and can expand.

With the 250 grain SMK I heard that they were a bit hard so I opted to try the Hornady BTHP Match projectile, instead as they have a higher B.C. anyway.

Results with these bullets was spectacular on over 100 feral goats at a muzzle velocity of 2730 fps from a Sako 24.5 inch barrel. Range was out to 495 yards.

I also shot a couple of large Sambar stags with this bullet DRT at close range, but I also lost one with a solid hit on the shoulder at 527 yards. (Dropped and rolled down the hill 15m, then go up and ran off on three legs, never to be seen again).

Have since dropped the MV of this load back to 2650 fps to maintain case life.

Thanks for sharing your real world experience. That is exactly the kind of information that I am looking for.

I am confused, however, by one thing. You state that the Hornady 250gr match bullet has a higher BC than the SMK. According to the information that I have on these bullets, that is not the case. The Sierra SMK is listed as having a BC of .587 and the GMK is listed at .565, while the Hornady BTHP lists a BC of .465. Unless I am missing something, I have to think that the Hornady left a lot of potential on the table at 527 yards. I sure wish that Hornady would come out with a .338 A-MAX.

Thanks, fellas, for your responses. It looks to me like the 250gr match bullets and 225gr Accubonds will be a good place to begin my load development. I will report back with my findings after I do some actual shooting and generate some real time data.
 
Quikload tells me the 300gr SMK can be pushed to 2550fps out of a 24" barrel
Take it for what it is worth.
Personally, I would shoot the 225 Nosler AB out of a 338 WM.
 
Benchracer, I have shot the 338 winny extensively through the years and currently have one I shoot regularly. You ask if the heavy bullets offered an advantage in this cartridge considering there slower velocity. In my opinion, no. You asked what velocity with the 300 smk. Most accuracy loads I tested topped out in the high 2400's with a 26" barrel. Just for your info the new Hornady 250 match bullet that came out last year has a higher BC than the 250 smk. I tried it and couldn't get it to shoot worth a flitter. The heavy bullets are accurate and will kill stuff just fine if that is your choice. Most of what you read about this cartridge considering it was designed to shoot 250 grain bullets and deliver a crushing blow was before some of the high BC bullets came on the scene and was considering average shots in the 300 yard range and closer. Please don't take sentences out of context on here or anywhere else without trying to understand the overall schema of what the guy was trying to say. There are some guys on here that have quite a bit of knowledge and will try and help you if you let them.

After quite a bit of testing with this cartridge the best option for me was the 225 AB. It performs well within the limits of this cartridge and will significantly outperform the 300 win mag or 30-06 on big game within it's optimum range. The slow velocities with the heavy bullets does not make it a top choice at extreme long range. In my opinion it is best suited shooting the 225 AB at 2950 fps. My longest shot with it was a moose at 1100 yards. My opinion is this cartridge is best suited inside of 800 yards and within that range the slow heavy bullets do not justify there use when compared to the 225 AB. You will find that opinions vary but that has been my experience. The 250 AB would also be a good choice but then you get into the recoil issue and I shoot mine without a brake. Best of luck with your choice.
 
Long Time Long Ranger:

If you carefully read what I have posted, you will see that I have taken great pains to point out that I am, at this point in the learning process, long on opinions and short on real world data/experience. In short, I am forming a hypothesis-- the first step in the Scientific Method. The point of my query is to find a starting place for my experimentation.

I have very carefully read and given thought to each response. Each response has been both valuable and appreciated. Those who have responded to my posts are helping me, and I am indeed letting them help me. In turn, I posted excerpts from each relevant post for purposes of clarity-- to make it clear what I had in mind when I wrote my response to their input.

AT NO TIME did I take ANYONE out of context. In fact, I challenge you to prove otherwise. Furthermore, your implication that I did not try to understand what was being posted is utterly baseless.

Your experience as a shooter and hunter is valuable to me and I thank you for sharing it with me.

However, you obviously have a questionable grasp of what it actually means to take someone out of context. I suggest you retire the tired old "you took me out of context" bit and dismount from your pompous high horse forthwith.

Most Sincerely,

benchracer
 
Benchracer, I was trying to help you. I have no interest in attacking you. I wish you the best with your choice. If I can help you let me know. I am sorry what I said offended you. I don't have that big a horse, heck I don't even have a shetland pony.
 
Benchracer:

You mentioned you don't have a reloading program. Did you mean a ballistics program for calculating downrange performance? If you don't have one you can get a great one free:


JBM

Here are a few steps to help you

Click on Calculations upper left
next click on trajectories
Enter data on your bullet.

Be sure to modify the atmospheric pressure. Bryan Litz says in his book that it is critical. Here are a few:
2500 27.32
3000 26.82
4000 25.84
5000 24.90
8000 22.23

You may notice the G1 box. If you open it you can find the G7 option. Bryan says that G7 is a better one for boattail bullets.

Here is the G7 BC for the 250 and 300 SMKs:
250 smk .314
300 smk .381

Buy Bryan Litz's book "Applied Ballistics for Long Range Shooting. Lots of good information there.

-----------------------

Until recently the idea of owning another 338 win mag hasn't appealed to me, but it sure does now. Not sure if you realize it but Berger is coming out with two high BC VLDs for in .338!

The BCs on these two is stunning. Predicted BC as follows:
250 VLD G1 BC . 762 or G7 .390 ( this beats the 300 SMK's BC!)
300 VLD G1 BC . 914 or G7 .468

The 250 VLD fired from a .338 would be interesting even though it wouldn't be moving much more than 2600-2700 fps from a 26" barrel. Crunch the numbers in that JBM. amazing numbers even for a slow moving bullet.
 
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