Most accurate powder for .300 WSM and 180 Gr Bullet?

[Dean44]

I am looking for the best powder for tried and true accuracy with 180 grain bullets and 300 WSM.

The rifle is a new Winchester Model 70 Featherweight. Factory 180 Grain Winchester ammo groups less than 1 inch at 100 yards - consistently. I then loaded some 180 grain ballistic tips with Magpro and groups opened to 2 inches.

I though it better to ask for your experience rather than buy a bunch of different powders at $25 a pound.

Thanks for your help!!

Dean44

[carpsniperg2]

I use H-4831 or H-4831sc in all of my guns over 25cal. It is the best magnum powder out there in my opinion.

[BallisticsNut]

My .300 WSM with 180Gr Sierra Gk, Federal 215 Primers, RL-17@66.9gr shoots sub 1" groups at 200 yards.  Also is getting around 3150fps. 

I have yet to finalize the test with 180gr Nosler BTs.  Same formula above except the sweet spot seems to be between 66.5-67.5gr RL17.  At 67gr, I started to see some flattening of the primers so I would recommend between 66.5-67.0 for testing. 

Give it a shot, let us know how you make out. 

[bhylton]

65gr imr 4350 185 gr berger vld, all stock browing a bolt, one hole groups at 100yds 3000fps

[sakoshooter]

IMR-4831 or H-4831. Maybe the SC but I don't have any personal esperience with it.

[KNOPHISH]

H4831SC for me also, Still working on the R17 loads. I'm using the Nosler 180 Accubonds.

[KillBilly]

http://data.hodgdon.com/cartridge_load.asp

Cartridge:  300 Winchester Short Magnum
Load Type:  Rifle
 
180 GR. SFT SCIR  IMR  IMR 7828  .308"  2.860"  65.0  2783  54,400 PSI  69.5C*  2943  62,600 PSI       
180 GR. SFT SCIR  Winchester  Supreme 780  .308"  2.860"  65.8  2779  52,500 PSI  70.0  2923  60,800 PSI       
180 GR. SFT SCIR  Hodgdon  H4831  .308"  2.860"  65.5  2775  52,000 PSI  70.0C  2929  64,000 PSI       
180 GR. SFT SCIR  Hodgdon  Hybrid 100V  .308"  2.860"  59.0  2728  50,200 PSI  64.0C  2918  59,800 PSI       
180 GR. SFT SCIR  IMR  IMR 4831  .308"  2.860"  62.0  2797  52,700 PSI  66.3C  2980  62,900 PSI       
180 GR. SFT SCIR  Hodgdon  H4350  .308"  2.860"  60.0  2799  55,700 PSI  64.0  2950  63,900 PSI       
180 GR. SFT SCIR  Hodgdon  H414  .308"  2.860"  59.0  2801  54,100 PSI  62.5  2959  63,000 PSI       
180 GR. SFT SCIR  IMR  IMR 4350  .308"  2.860"  61.0  2808  52,800 PSI  65.0C  2991  63,700 PSI       
180 GR. SFT SCIR  Winchester  760  .308"  2.860"  59.0  2801  54,100 PSI  62.5  2959  63,000 PSI       
180 GR. SFT SCIR  IMR  IMR 4007 SSC  .308"  2.860"  57.0  2806  56,800 PSI  59.8  2927  63,000 PSI       
180 GR. SFT SCIR  Hodgdon  H380  .308"  2.860"  57.0  2718  53,700 PSI  61.0  2884  63,400 PSI 

[Bigshooter]

I'm a big Mag Pro fan for any of the wsm.

[BigFoot02]

I have been loading with 4350 IMR with 64g of powder... That load has proven to be acurate and put a hurtin on deer and antelope..

[MDGrand]

I will have to offer that what you are asking for is tough to deliver. What I mean is, every rifle is different and will like a different load. What will work in my rifle probably wont be identical in yours. My 300 WSM Vanguard Sub MOA ironically does not like the 180 XP3 factory ammo as much as it loves Barnes and Berger.

 If you are working up some loads and found out that your rifle likes the factory winchester. I would 1. make sure to keep the brass. 2.measure the OAL of a bunch of rounds, then 3. find how that compares with the OAL guage of your bore and write that down. This should tell you how seated the bullet is and how far from the lands the bullet is. 4. I might take a few apart just to see what the weight of each powder is as well. 5. Finally, I would go buy about 2-3 powders... RL 17, IMG, Hodgdon and work up some loads.

* A key thing to remember on this is that factory ammo will vary in powder weight and OAL by a few 100ths or so.. this is common. I would take the average of all of those.
 

[engelwood]

There have been a few suggestions for RL 17, I just loaded up some bullets with RL19. Is there a reason that people are preferring RL17 over RL 19 for the 300 WSM? New at this... thanks!

[timberghost72]

I am using IMR 4350. This is the only powder I have used for my 300WSM so I don't have a comparison but it shoots very good. I have loaded 165 grain and am going to load up some 168 grain and see how it does. I havn't loaded for 180 though.

[engelwood]

I also loaded some with IMR 4350. I'm interested to see what kind of groups I will get out of these new "hand loads". Looking forward to it.

[carpsniperg2]

I also loaded some with IMR 4350. I'm interested to see what kind of groups I will get out of these new "hand loads". Looking forward to it.

The books say you will be around 50fps faster with the r19, over the imr 4350. In the 300wsm.

[JKEEN33]

My 300WSM likes both IMR 4350 and 4831.