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Wanting more velocity out of 338 WSM

VARGET will be your friend. I've been where you are. I love WSMs and H4350 is my go to powder in my 300 WSMs but it's too slow when you get into bigger calibers. At least that was my experience.... In my 338 WSM it gave fair accuracy but slow. I hit pressure quickly while trying to get up to a desired velocity. I am using 63 gr of Varget behind a 215 Sierra Game King at just a touch over 2900. My average velocity is 2910. I run Varget in my 358 WSM too. It pushes a 225 Sierra Game King at 2840ish.
The 338 has a Hart barrel and the 358 has a Lilja.

Don't start with my load. It's very close to MAX pressure. Back off of that and work up...

I hope this helps!
 
I am at 2.945" and was at 2650 with 59.5 gr H4350 with no pressure and sticking cases. I was 62.4 gr h4350 on first firing at 2760.
Your statement does not clarify whether you had pressure at 62.4g H4350 2760 FPS; if so, drop your charge to 61.4g H4350 and re-evaluate for 2700 FPS. I would take accuracy over velocity anytime, especially when there is only a 50 FPS difference from your 2750 FPS goal. Whatever safe velocity you end up with, adjust (dope) accordingly to your intended purpose at range X.
I'll be happy with a consistent 2700, I think that should be achievable.
 
Haven't read all pages.
I built my first 338-300WSM on standard length actions in the early 2000's.
We could not get within 100fps of regular 338WM velocities with bullets from 200g to 225g, 250g bullets fell short by 150fps.
I am sure this is why Winchester never did a factory 338WSM.
The only powders we could get to work were RL17, much later on, and Win 780 Supreme (now discontinued). This powder is the same as 785, 780 & one of the other brands which I forget it's nomination.
H4831 works, but velocities are slower again. RL19 also worked, but again velocities are slow.

I hope you can delve into a powder that boosts performance because we never did, I haven't touched a 338-300WSM since about 2013/14.

Cheers.
 
By looking at your pics, and seeing how far out the bearing surface of the bullet, is...

I'm guessing your bullet is jammed, and causing pressure spikes

Unless you have a freebore reamer of .100" to .125" or so.
 
Not sure if it will work for 338wsm but a buddy shooting 300wsm 225 grain pill shoots n540 gets plenty of speed and tiny groups at 600 yards and 1000 yards
 
Played with it in GRT a bit. No VV powder can get you to 2700 fps but if you are set on VV, then N-555 was the best option. N-565 is just too slow burning. Reloder 16 and 17 can get you to 2700-2750 with max charges
 
I have some data for two cartridges that are similar to what you are using.

Friend had me work up a load for his 22" Browning A-bolt with Boss years ago. Chambered in 300 WSM. Used 230 gr Berger for 2735 fps using 61 gr of RL17 mag primer, win brass. COAL was 2.8".

I own a 22" 338 RCM and use 225 Accubonds, 210M, 54 gr of varget 2733 fps. Cartridge COAL is 2.950"

You mentioned sticking cases with a relatively low load of H4350. Did this sticking happen often? More detail on what exactly is sticking would be useful. Hard bolt lift? A hard click at end of upward movement of bolt handle? Or difficulty moving the fired case rearwards?
 
I have some data for two cartridges that are similar to what you are using.

Friend had me work up a load for his 22" Browning A-bolt with Boss years ago. Chambered in 300 WSM. Used 230 gr Berger for 2735 fps using 61 gr of RL17 mag primer, win brass. COAL was 2.8".

I own a 22" 338 RCM and use 225 Accubonds, 210M, 54 gr of varget 2733 fps. Cartridge COAL is 2.950"

You mentioned sticking cases with a relatively low load of H4350. Did this sticking happen often? More detail on what exactly is sticking would be useful. Hard bolt lift? A hard click at end of upward movement of bolt handle? Or difficulty moving the fired case rearwards?
When I first started loading for this gun I was using nosler brass and using 62.4 gr of H4350 with no issues on first firings. Second firings with that load on that brass didn't seem to have any issues either. 3rd reload on that brass and the brass wasn't forming with the die anymore and moved on because i figured it was too hard and needed annealed. I moved over to the norma 300 wsm brass and didn't have any issues until it was once fired. After second firing the cases started sticking and couldn't get the bolt pulled back (hard lift but no clicking on lift). I snaked out the chamber and throat and found some carbon build up so I cleaned the crap out of it thinking that was the issue. Still was having the same sticking after a very thorough cleaning. I might move back to the nosler brass and just push it hard and toast it off after 2nd firing and that might get me back to my original load and velocity or close. I was just hoping maybe it was powder choice since I haven't played with any other powders with this setup other than H4350. With the feedback I've received on this thread it appears that I need to try RL17 and stay with powders in my current burn rate or just stick to a little lighter load. Which is fine, I'm not far off and not losing much at 2675. Again due to my lack of experience with powders in this setup, I thought there might be a quick fix solution by swapping over and poof be back in that 2750+ range.
 
By looking at your pics, and seeing how far out the bearing surface of the bullet, is...

I'm guessing your bullet is jammed, and causing pressure spikes

Unless you have a freebore reamer of .100" to .125" or so.
I'll call the gunsmith and get that answer when I get a chance. I know he does really really good work so I trust that the OAL we landed on of 2.945" was appropriate but I'll double check with him.
 
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