Gang, I have been shooting some small groups with 72.0 grains of Rl-19 in Win. nickle and reg brass, CCI-250 primers and Barnes 140 XBT impact moly coated. COL is a short 2.780". This load is shooting well in two rifles..a Factory WinM70 blue with laminated stock and a custom TC Encore with a 24" med varmint barrel. Both of these barrels have been treated with KG 6 moly bore prep. Ive only been shooting at 100yds but I dont even want to post the groups sizes... lets just say that several have been sub 1/2MOA. Hope to try these on a white-tail or two in the upcoming weeks. After that I'll work ups some loads with some moly coated Nosler 155 J4s.
Somebody els try this load and let me know how it does.
Dave

Dave have you tried Imr4350?

Chuck

Chuck, I have not tried any IMR but I have tried a bunch of H4350 loads with the best by far being;
64.0 grains
Fed 210M
165 grain Hornady SST moly coated
COL 2.870" which is kissing the lands in the above Encore.
I only loaded three and they shot into .612"
I'm going to load a few more of these and some with 215M primers and shoot em through a chrono.
Have you a good IMR 4350 load to share?
Thanks for posting
Dave

Dave,
Yes, extreme accuracy and speed to boot with I4350. I have loaded for two 300WSM's and both have liked it. The light gun likes:
72.5gr I 4350
150gr. Sierra (it shot all 150's alike)
3430 FPS
Winchester Brass
215M Primer
Remington 700 (Blueprinted)
Kreiger 25in. Brl
Three 5 shoot groups avg. .23in.
This was a hunting gun so we stopped there.
The best group was .183
The heavy gun:
67gr. I 4350
190gr. Sierra Matchking
3118 FPS
Winchester Brass
215M Primer
Nesika Bay J Model
30in. Brl
Many groups all better than the first gun.
This gun was made for Prairie Dogs from 1000 to 1500 yds.

I also used 4064 to break in the barrel and the largest group there was .80 with speeds up to 2959fps and I stopped at 57.5gr.(190gr. bullet)

Good luck
Chuck T.

Dave I am interested to know how your loads are going. If you did load some 4350 and how that came out.

Chuck

Chuck, I havent had a chance to lately. Ive been spending my time in the woods instead of at the bench. My neighbor has taken 4 white-tail does with one of the 140 grain loads above and three with 2 shots with the same load under a barnes 130XLC. All of the shots have been between 120 and 225 yards. Yes the last was a two with one deal. The 130 blew through 3 shoulders and exited the behind the offside shoulder of the second doe. He calims none of the deer have taken a step after the shot.
I should be able to get some IMR 4350 in some cases over the holiday.
Thanks I'll let you know.

Dave,
Like you I have been hunting all the holiday's only for birds though. I will be watching for your results. It will be spring before I get to really test mine on Dogs for those 1000 to 1500yd shots.

Chuck T

Gentlemen, I ran a little test last year when I first aquired my 300 WSM (SS M70). I loaded a batch of 180 gr. BT's (Federal Deep Shok's) with H4350 using WLR and WLRM primers. With identical powder charges I got identical velocities, but ran into pressure problems with the magnum primers and could not load more powder, whereas I could continue a bit with the standard primers (WLR) obtaining HIGHER velocities with lower pressures than with the WLRM primers. As was originally reported when the WSM was unveiled, magnum primers are not advisable with this case. I believe this is part of the problem with some of the conflicting data regarding the WSM (Nosler manual uses magnum primers). As to cold weather... well, here in Montana in genuine cold I've not found the need for them in the WSM.

As an aside, I blew a good chance on a good bull last week so ended up taking a nice sized cow with handloaded 180 gr. Failsafe's yesterday. The range was around 325 yards. I put the first shot in the boiler room though the old gal gave no indication she was hit. I put another shot in the lungs and she rolled fifty yards down a burnt hillside coming to rest against a tree... stone dead.

Brad

Brad,
After reading your post I realized that I put the wrong primer in that load and you are most certainly right that the 215 primer is to much.

Chuck T

Chuck, I'm by no means saying mine is the definative word on the subject but my experiment certainly gave me pause. Honestly I can't explain the results, but they are what they are.

I'll be interested to hear what you find.

Best Regards,

Brad

Brad,
I had just been loading for my 375H&H and had 215M on the brain. But when first loading for the 300WSM I read lots of data to support this and that is what I did and have not had any pressure problems as others have experienced.

ITS MY OPINION and only my opinion (without getting a fued going) that 300WSM is the best 30cal. on the market, Considering what it is intended to be.

And I say that without slighting other calibers. Because I feel that there is not a bad one they all have there own uses.

Chuck T