Home Forums Reloading Big Game Rifles 300 wsm and 200 gr bullets

The only compressed loads I ran into was a 200 AB(at 2.880"COL) and +68 grs of H4831sc and a caseful of R22 and 180 TSX.
Trying to remember but I think the powder was crunching enough that I used a droptube. Not too big of a deal

Mule, Bigsqueeze,

For whatever it is worth to either one of you, I don't have a copy of a Sierra reloading manual and never have owned one. The three I get my load data from primarily are Nosler, Hornady, and Swift. Occasionally, I will get data from powder companies, but most of the time, I get my data from the 3 manuals I just named, and I never consult the commentaries other than maybe to see where the chambering in question originated from.

I simply did not care for the bullet drops I got in Canada 3 years ago when I shot 2 different 200-grain loads, and I loaded the things almost religiously and exclusively when I lived in Alaska. I'm one of those people who likes to find reasons why something went wrong and try to fix it. When I compared an unloaded bullet to one which was fully seated into a loaded case, I simply arrived at the conclusion that the reason for the drops I observed was that the bullet itself was cutting too far into the case's powder capacity, thus negatively affecting its downrange performance. Never at any time did I consult a reloading manual to arrive at that conclusion.

And no, the .300 Win would not necessarily be subjected to the same reduced capability as was previously described. The reason has to do with the fact that there will be more powder in the .300 Win Mag casing than in the .300 WSM, and that difference can be as much as 15 grains depending upon the powder you're using.

I am someone who loves shooting his .300 WSM, and in fact, it is the one rifle which outperforms everything I've ever owned. Even still, we would all come across as being terribly naive if we didn't recognize that there are limitations with every load and chambering we could name, wouldn't we? The 180-grain load is no slouch in the .300 WSM, and it may be the best overall choice for that chambering.

What we have all been discussing may be a big part of why ammo companies aren't loading too many 200-grain rounds in the .300 WSM. In fact, right off the top of my head, I cannot think of even one company which is doing so.

SPH, what's your favorite powder/bullet for the 300 WSM.

Brad's reports got me to give R17 a try.
Glad I did, H4350 was good with 180's but I like R17 even more.
Very consistent powder and IMO less sensitive to temps than H4350.

175 SMK's/Nosler CC's and 180 Partitions shoot great.

I am very fond of my Kimber classic 300WSM. I have a new load which consists of a 180 accubond over 61 grains of Viht N550 with a CCI LR magnum primer. This lays 5 of them into an inch at 100. I wish I had a 300 yard range to shoot at, I need to practice at further distance. So far I am very fond of that Kimber, I guess I will just shoot it until the barrel wears out.

Mule Deer,

Amazing how one guy at a gun show can decide you represent "all" gun writers. Instead of just asking for your opinion of using a .270 in Africa...

Reloder 22 & 180-grain Nosler Accubonds. I prefer using Winchester Long Rifle primers when available, but right now I have to take whatever I can get my mitts on.

Speer Grand Slams are a close second, though.

I've used RL22 behind a 200grn Nosler Partition in my .300 H&H for years. It works great on elk.

I tested some 200 gr NP loads in my 300 WSM LH Win 70 yesterday.
WW Brass CCI Mag primer 61 gr of RL 17 3@ .75" @ 100 yards. Forgot tripod for the chronograph. Went up to 62 gr of RL 17 but accuracy was around 2.5".

I worked up a load with 61.5 gr of RL 17 and the Nosler 200 gr Partition, will go out in a few days to check for accuracy.

Let me know what kind of velocitys you get with 61 gr of RL 17 & 200 gr bullets?

It will be a few days before I get out to shoot again, going to try to go out either sunday or monday.

Finally got a chance to see what the 200 gr partition will do with 61.5 gr of Rl 17. First group went 1.47 inches, two rounds close togeather and one round about 3/4 inch to the left and 1/4 inch high. Second group measured 1.12 inch with two rounds almost touching and one off to the left and high, the third round produced the flyer on both groups. I am at 2.850 oal, thinking I should seat the bullet out a little more.
Chrony results were very good, I used once fired brass for all the tests.

1. 2766
2. 2783
3. 2777
4. 2772
5. 2783

Average velocity 2776
Extreme spread 17
Standard deviation 7
Thats the lowest SD that I have ever gotten with any load.
If I can get a good group without a flyer it's looks like I may have a winner.

I have had really great luck with 58 gr of H4350 and the 220 gr Sierra Match King. My 5 shot groups are sub .4 MOA. Shot out of a 1:10 Hart barrel.

Just one more comment on this thread. It's easy to predict what velocity a new bullet weight should get in any given case by a simple mathematical formula, if you know the potential velocity of another bullet in that case:

1) Add the two bullet weight together.
2) Divide by two.
3) Divide the new bullet weight by this product.
4) Multiply the result times the velocity of the known bullet.

Let's use the .300 Winchester Magnum as an example, and figure out how much velocity a 200-grain bullet should get, figuring from a 180-grain at 3100 fps.

1) 180+200=380
2) 380/2=190
3) 190/200=.95
4) .95x3100=2945

So we should be able to get around 2950 fps from a 200-grain bullet in the .300 Winchester Magnum. This is about what most manuals suggest.

If we apply the same formula to the .300 WSM, using a 180-grain at 3000 fps as a starting point, it suggest we should get 2850 fps from a 200-grain bullet. Again, this is about what most manuals suggest is possible.

If a 200-grain bullet were actualy reducing the potential of a 200-grain bullet's velocity in the .300 WSM, then a 200 wouldn't reach it's mathemmatical potential. But it does.

Guessing that a 200-grain bullet is being some reduced in potential because it drops more than a 180 at 300 or 400 yards is faulty reasoning. Of course a 200 will drop more than a 180 at such ranges, because it starts slower--but how much aparent drop can also be vastly affected by a little difference in 100-yard sight-in between the two bullet weights.

Also, the type of powder used can have a big effect, especially in cold weather. I have seen some powder lose 150 fps or more in muzzle velocity in codl weather. This affects long-range trajectory a little, but it can also affect 100-yard sight-in a LOT, in exactly the same way that point of impact can change between loads with different powder charges when we're working up a load.

Trajectory is determined by muzzle velocity. If a 200-grain bullet chronographs 2900 fps from a .300 WSM it will have exactly the same trajectory as when it started at 2900 from a .300 Winchester Magnum.

Shot my 300 WSM Win 70 24" today with 200 Gr Nosler Partions,

Loaded 3 shots with CCI Mag Pr & RL 22 67 Gr 2759, 68 Gr 2816 &
69 Gr RL 22 2868 FPS. 66 Gr was around 2700 FPS.

With my test loads of RL 17 & 168 Barnes TSX I worked up to
3250 FPS reduced one grain to 3150 FPS.

As Ramshot does not have data for the 200gr bullet and Hunter, I contacted Johan at Western Powders and asked him for some recommendations for my 300WSM and 200gr bullets. This is his reply.

Caliber: .300 WSM � Winchester Short Magnum.

Barrel length: 24�

Powder: Ramshot --- HUNTER.

Bullet weight: 200 grains.

Start load: 56.7 grains (2500 � 2600 ft/p/sec)

Maximum load: 63.0 grains (2800 � 2900 Ft/p/sec).


I don't have my numbers in front of me, but if I recall correctly my velocities were pretty close to his data in my CZ Model 3.

Great tip, thanks!

Went out and shot some more groups, seated the bullet out an additional .010 from 2.850 to 2.860 oal, groups went from 1.17 inch to .959, flyers are gone. I am satisfied with this performance.