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Wanting more velocity out of 338 WSM

With wildcats, you have to do your own research. Keep trying slower powders until you have a load that is too compressed and can't get pressure signs on the case. Give up the easy button and do the work yourself or buy saami stuff. Quickload is only an approximation that over compensates for thing like powder lot variations and etc. You have to do this all alone. Use mid range 338 rcm stuff for starting loads and do work. Good luck.
 
With the fired brass giving you issues, it sounds like the same sort of issue that happens with the 6.5 PRC. There are several articles on the subject. IMO Alex Wheeler did a good job of explaining this problem. In a nutshell the chamber is too tight near the case base and the dies cannot size fired brass enough for easy extraction. Some cases are stoutly built and once the base diameter increases and won't be sized back for easy extraction. It can be the die you are using, or the chamber is just too tight in the base area.

The solution is to use a reamer that is a bit larger in the base area or sand that portion on an existing barrel. I have seen this sort of thing with the RUM, WSM, and RCM cases.

Before this was common knowledge, I made a small base die by cutting down an extra RCBS FL die removing the top and bottom with a carbide tool bit on a lathe. It helped with a sticky RUM that my friend and I have, but wasn't perfect.

After the clicker discussions, I took the two 338 RCM barrels off my rifles and chucked them up in the lathe and sanded the base portion. This fixed the issue.

You can view two videos on this subject. Die fit and clickers found here:


Hope you get it figured out.
 
2.945 is just fine. My buddies 24" 338 wsm I built him is on a short action and loaded to an oal of the same. It with a max load of h4350, 230eld and Winchester brass, it gets 2850. If your first firing is fine and your sticking cases on your second firing there's an issue with your chamber/barrel.
One of my reamers has zero freebore and it dosnt touch the land until about 3" so I highly doubt your jamming
I guess I always thought that the BTO measurement was more important than the COAL measurement?

Thanks
 
I guess I always thought that the BTO measurement was more important than the COAL measurement?

Thanks
I measure CBTO to determine bullet relationship to the lands. For some this cann be controversial. I also find it to be easier and more reasonable to measure. COAL measurement is important in magazine clearance. The WSM thrives greater than 3.00+" COAL. Most will find the best compromise between CBTO and COAL.
 
A sub 3 in OAL will hobble all WSMs, the closest one that kinda fits a 3 in COAL and gets performance is a 270 WSM with a 140 gr bullet. The WSM thrives in a medium length or standard length action, I wouldn't build them on a short action after the first one I did, also need to match the reamer to die diameter to eliminate second firing issues. You might just want to find the best accuracy powder and let the velocity be where it may, R17 will usually really kick things up but it temps swings horribly and I didn't find it usable for my applications but might work in yours.
 
With the fired brass giving you issues, it sounds like the same sort of issue that happens with the 6.5 PRC. There are several articles on the subject. IMO Alex Wheeler did a good job of explaining this problem. In a nutshell the chamber is too tight near the case base and the dies cannot size fired brass enough for easy extraction. Some cases are stoutly built and once the base diameter increases and won't be sized back for easy extraction. It can be the die you are using, or the chamber is just too tight in the base area.

The solution is to use a reamer that is a bit larger in the base area or sand that portion on an existing barrel. I have seen this sort of thing with the RUM, WSM, and RCM cases.

Before this was common knowledge, I made a small base die by cutting down an extra RCBS FL die removing the top and bottom with a carbide tool bit on a lathe. It helped with a sticky RUM that my friend and I have, but wasn't perfect.

After the clicker discussions, I took the two 338 RCM barrels off my rifles and chucked them up in the lathe and sanded the base portion. This fixed the issue.

You can view two videos on this subject. Die fit and clickers found here:


Hope you get it figured out.
Very informative. I dunno if I want to get too crazy for a little added velocity. But I think I might play with different brass and RL17.
 
Try RL-17, which is made for WSM.

View attachment 635585

I was getting 2850.FPS with 215 Berger out of my .300 WSM 24", so it might get you to 2700 FPS. I think you are closer to your goal than you think. The RL-17's burn rate is nearly the same as H4350. The H4350's propellant has its energetic component with only nitrocellulose, and the RL-17 also has nitroglycerin to help generate higher energy (performance) in the propellant.

Good luck!

ADDED:

I experimented with H4350, H4831SC, MagPro, IMR 7828 SSC, and H1000 before settling with RL-17. Below are the highest velocities I achieved before hitting pressure.

65.2 H1000 = 2667
67.9 MagPro = 2675
58.5 H4350 = 2679
63.8 IMR 7828 SSC = 2681
62.9 H4831S = 2700
62.5 RL-17 = 2850

As with anything else, YMMV.
I agree RL 17 if you can find it. I'm getting 3050fps in A 300wsm with Barnes 180gn TTSX.
 
I wouldn't compare the other WSMs to the 338 or even the 358. The bigger case mouth makes a big difference. Look in the manual at a 325 WSM. There is a reason faster powders like Win 760, H414 and VIHT 160 are recommended.

As I said in my previous post, Varget works great in both both my 338 and 358 WSMs.
 
I wouldn't compare the other WSMs to the 338 or even the 358. The bigger case mouth makes a big difference. Look in the manual at a 325 WSM. There is a reason faster powders like Win 760, H414 and VIHT 160 are recommended.

As I said in my previous post, Varget works great in both both my 338 and 358 WSMs.
I use varget in my 338 ss and it performs great
100% agree
 
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