WC 857-300wm

Probably not news to many here but I was pleasantly surprised on a recent outing.
The tool: Mod.70 crf. 10 twist,22.5 "barrel.
Components: once fired FC, Wlrm primers,WC 857 powder, hbn coated 208 Amax bullets.
Atmospherics: 75*, 40% humidity,5500da. winds 5-8 variable.
Doing a ladder test starting at 78 grain, working up in .4 increments.I hit the wall at 81.6 grs,Stiff extraction!belt expansion,.00075- .001". 2965 ave. 22sd. .4 less, everything looked good,2930 av.11 sd, sub moa group ( only three shot ). I was pleased with the speed and sd. as I never expected that much out of a short barrel with this slow of powder. Shows a man don't know everything regardless of years or experience.
DO NOT TAKE THIS INTERNET POSTING AS A RELOADING GUIDE ! it is only anecdotal to my rifle, my components and on this day!!!!!

Cool, I have had excellent results with my 25-06, 270, and 243 at medium speeds and using heavier bullets (as expected). I need more time with my 7mm Rem/mag which is a close load to this load you posted-- super info to me!!! (and I've been using this stuff for 5 years- bought six jugs ;).

I have posted here (and at other forums) some excellent smaller caliber (duplexed) loads using this powder too. But my hopeful this year is trying this WC857 in my new 270 WSM build (and I also have a 25 WSSM about ready to play with too). The short, fat stuff with tighter necks seems to be a "fit" to this slower powder. Compared it to factory Rem and Fed 243 loads (100g bullets), and it was as fast as Rem (and faster than the Fed loads by 100 fps). It's cool burning and for my 243, 100g Sierra GKs-- it shoots as good as anything else with good SDs and hey... it's fast enough at about 2850-2900 (depending on the barrel for my 243, 100g loads!).

HAVE YOU ANY OTHER CALIBERS TESTED?

Cheers!

I have about 30 lbs of this....does yours have the lot number available?

Smalltown ,lot# 49376

Txnagal, currently wringing out another 300wm.with 857, 26" match chamber, it is working well! 308 subsonic project to finish up, then on to more 857 work-ups. Next will likely be a 7saum with 180's aka. Montana death laser. This will be a good test as it is currently working verrry well with an H1000 load.

Sorry Cavhasbeen,

I fell into the garden for the last three months. The 270 WSM and 25 WSSM are on hold due to rare (and expensive) parts still being acquired. But I have put together a pair of 260ai barrels (one in a 25" sporter, other in a 27" bull barrel - same reamer) So the plan is to use the 25" for working out course load work (while fire forming brass to match the 27" barrel). The long barrel still needs a stock, but the 25" is about ready to go and I plan to play with this WC-857 to see how close it gets to the Allaint RL-26 loads I've been reading about lately (which are outperforming Terry Cross's famous 4831sc load by 150 fps -or so). Not sure how much I can get into the case though- so have to see how the density works out.

I have moved on from my duplexing days as it was so time consuming. I learned a lot though and I REALLY love using this 857 in my 243. I now just fill it to a lightly compressed load on a 95g - 100g (don't even measure the weight- literally just fill it to about 5mm below the case top, seat the bullet and go hunting). IIRC, it was good for 2850-2900fps with the Sierra 100g Gameking when I cronied it originally. This basically matched a standard Remington factory round I compared it to then (and beat the Fed factory cartridge by 100 fps too). It's made my 243 a go-to gun for coyotes, white tails and anything here in Kansas I might want to hunt any given day. It ran well in the 270 too, but my pet load of H4831 is just so familiar to me in my one gun that I will be using it going forward (and it's speed at 3050 fps is easily 100 fps over the 857).

But I am really looking forward to getting the "WISSUMS" built up this winter to see how the 857 runs in those fat Jefferies cases. I also have the 7mm Rem Mag to play more with here too.

Anyway, let us know how the Saum "laser" works out!

** Smalltownguy... my jugs came with no lot #s (and mine has none of the green flakes a few have reported).

Well as it is snowing it's a$$ off today I decided to run a few 300wm. rounds to check the cool weather data. I loaded coated 208 amax's over 81.2gr. of wc857 in fed brass w/215 primers. Left them outside in 33* weather for an hour and a half, then ran them across the Mag.speed. Results were 2774fps with an sd of 9. Lost 156 fps from my summertime loads or a bit over 3fps per degree. Guess it don't qualify as temp. insensitive.I'll try and run some rounds when it gets down 20-30 below just for educational purposes.

Merry Christmas to all!
I took the opportunity this morning to run a few more of these to try and plot the speed changes due to temperature change. The loads were the same as the above listing.I cold soaked the loaded rounds outside at -10* F. The speeds were nearly unchanged at 2776 fps average. I had predicted speeds to be in the mid 2600's. Wrong again. I intend to try and gather further data as the winter progresses.
As an aside I also chrono'd my 308 subsonic loads. They have been unchanged speed wise from 85* down to -10*. I am declaring Red Dot stable for my purposes.

Hey CAV,

I just loaded up a string of my WC857 for my 7mm RemMag for a run out to the range this coming week. I have had a few 160g partitions for a while that I've wanted to work a load up for in this 24" Model 700. So I started with H870 data less 10% and will fire in 1/2 grain steps until I get a sticky bold/flat primer-- then I'll load a few strings right below that pressure point and go from there.

EDIT: Went out and shot the first string-- loaded from 78 - 80 in .5g increments. I didn't get past 78.5g with the 7mm Mag w/160g Partitions in Rem brass/cci450:

Shot #1 - 78g WC857 @ 3130fps (sticky bolt)
Shot #2 - 78.5g WC857 @ 3149fps (stickier bolt)
Shots 3-5 (did not shoot, of course)

- stopped here... will pull remaining loads and drop to 77g. and load UP in .2 increments. Although the bolt was about the same "stiffness" on the two 78g and 78.5g shots I was able to get off-- it wasn't too hard to open with a slight fist bump on the lifted bolt ejecting the case without too much force. So I'm pretty sure I'm close here.

ANYTHING over 3k FPS is totally superb and I'm pretty sure this is going to be a GREAT load after I tweak it here. From past experience, I'm guessing the final load here will be hitting around 3075 or so.

My Speer #11 (1987) load manual has H870 listed at the top with 80g @ 3009fps. That is the fastest load listed in that manual (with IMR7828, IMR4831, and IMR4350 all running about 25-60 fps behind it)

My Hornady #7 (2007) has SEVEN powders listed to hit 3kfps: H1000, IMR4831, RL-22, AA3100, Win WMR, H-1000, RL-25, and Magpro.

On temp sensitivity, I recall every string I started (with the 243 loads) shot the first cold bore shot a bit slower then the rest of the string (which went up about 15-20 FPS with a warmed up chamber). The SD was never really tight with the 100g bullets I loaded for. But my experience still was great accuracy-- with easy 1" groups out of my Savage Axis (tweaked) rifle. I can see where the 1000 meter guys might have concern (for cold bore shooting) with this powder, but for a deer (or other game) out to 300 yards (my 243 limit) the delta between a cold and warm bore is not a concern. Compared to Federal factory 243 rounds (from about 2012 or so), the WC857 ran a bit faster. But these same loads were about 30-40 fps slower than the Remington factory loads (bought about 2015) when I tweaked this load (about four times out) in late 2016.

Anyway, Jeff Bartlett still shows this powder available at GI Brass and I might just have to get another six jugs of it if it shoots good in my 7mm Rem Mag AND my soon to be finished 260ai (same case as a 243, but with a more open bore + larger bullet- WC857 might work well!). I DID hit some light pressure with the 243 105g amax loads I worked up with this powder- so perhaps it will even out some with 140 (or 147 ELD Hornady) bullets- TBD. As the 260ai is a LIGHT hunting gun, bullet speed is not essential-- and if it's MOA or better (like my 243) I'm happy to shoot $10/lb. powder in most of my hunting guns (but my 270... although the WC857 shot great in my 270 too-- I have old H4831 load for than one gun that hits exact POA EVERY time-- so if it's not broken... ;)

Glad you are being productive TX. I was a bit surprised you hit the wall that early with the 7 mag. Personally I have declared a moratorium on working up serious loads with 857 'til the weather warms.
With my propensity to run things pretty hard I want to establish my loads in hot weather. The results I had with the 300 dropping so many fps due to lower temperature have made me nervous going the other way. Seems the possibility of a safe load at 40*turning into a wreck at 80* dampens my curious nature. best, S.

Yes, I HEAR you loud and clear on temp concerns!

I used to ride that edge more often myself, but I'd rather find the accuracy nodes first, then decide the ACCURATE load's usefulness (during whatever weather condition if falls into). As I only hunt winter times with my 7mm mag (elk gun), my useful temp range will be 10 - 60 degrees where I hunt in NM. But as I'm hitting some VERY nice velocity at a lower than expected load while testing yesterday-- I'm going to be happy to back it down to a safe and (crossing fingers) accurate load-- got to do the work to find that node IF it's there.

Luckily for me, I have days in the 50-60s coming up and so I'll be working on this at this rifle's peak temp range of use. I doubt I'll ever run my rifle in anything sub-zero and on those coldest mornings where I hunt-- a few of my rounds stay in my pocket (until things warm up or the LONGER shot is lined up). I have killed VERY few elk under 250 yards, and I hunt hard, open country. So I have time to stalk, set-up and dial-in most shots before chambering a warmer round for that longer shot. And IF I get a short, fast (5 degree), early AM opportunity-- velocity can be down 200 fps with super-cold rounds in the chamber--- it's not going to matter at 200 yards in on an elk ;)

I was reading about the Kirby Allen Customs (extreme long range rifles using big cases) and although I don't shoot elk past 500 or so, his guns get WAY out there. He once said he just used drop charts for his loads based on temp sensitivity-- so one for warmer, and one for colder hunting (not sure if he changed the load's powder amount for each chart, but I don't recall him saying he did). He uses a lot of this WC857, WC870, and WC872 in his builds so he's got some good tricks there I think (and my drop chart is taped to my rifle for ANY long range hunting I do). I'd guess a lot of the longer range bench guys might adjust for some powders out there (if even a little) if they give them the performance they want.

So, my last thought on a hot summer load... is that even if it gets a bit over-pressure, WC857 has been manageable in my case. The 243 and 25-06 loads I definitely rode hot (in NM a few years ago) using WC857 and the heaviest bullets (105g and 120g respectively) didn't blow primers or act too scary (like some other powders out there do when you go over). They just shot a bit faster, flattened the primers a bit, and had some stiff extractions. So I learned my lesson out there (in 90 degrees) with this powder and backed it all down a touch (but accuracy thankfully stayed good on BOTH those particular rifles).

So hopeful here for a final load that is accurate and within around 3000fps... and I'm feeling real good about the wiggle room with my first test here-- and GREAT velocities JUST slightly over-pressure. I should be able to back it down to an accuracy node but have pretty good speed. if I can, the bag of Partitions I have will be a lifetime supply and I'll be happier with this bullet for the longer range shots I do take on elk (and knock on wood-- I'm 100% 14-14 elk, shot and eaten since 1992)-- we'll see what happens and report! -Cheers! -TX

I quit putting holes in meat critters a few years ago other than maybe a whitetail in the fall for my bride to can. Mostly I shoot steel, paper, and wood with the occasional pest or predator thrown in. The predator / pest issue is becoming a lot more frequent it seems. The 150 fps swing I noted with the 300wm would likely put me completely out of an accuracy node, unless I happened to blunder into another node.
I should have tried to find one in the cold weather but being old, fat,and lazy I didn't feel like blundering through 4 feet of snow to check and change targets. I may try and load down to match the cold weather speeds and see how that shoots. best, S.