Feedback/Advice for 300 WM loading noob

[AccuracyAddict]

Morning all,

I have been reloading for about 6 years for target shooting with short action cartridges and heavy barrels. However, I just picked up what will be my primary hunting rifle last week with the following specs:

Rem 700 LH action
ER shaw #3 1:10 at 24" + muzzle break in 300WM
Manners. MCS stock w/90% carbon fill
Hinged Floorplate BDL bottom metal
Timney 510 trugger
Seekins 20moa base
Vortex precision matched rings
Vortex HS 4-16x44 w/MOA reticle.

Took it to the range last weekend and was just getting a feel for it shooting some old factory Winchester 180 gr powerpoints. I had previosuly cleaned the barrel and after fouling, it shot a .352" 3 shot group at 100 yards, but that was the best of the day. Barrel got hot and opened up as smaller contours do. Anywho, previous owner said it shot .75" regularly with 200 accubonds and RL-22.

I've never loaded 300WM for hunting and done load development on thinner barrels and wanted some feedback for my intended plan.

So I have some fired WW super brass that I measured headspace for. I intend to set my redding master hunter die set to use the FL sizing die to bump shoulder .002". I have some 200 gr accubonds I picked up but don't know if I want to use rl-22 or a less temp sensitive H4831sc or h1000. Anyone have advice on powder?

The next questions are regarding OAL. I did some measurements with a OAL gauge and noticed my loads would have to be 3.600" to be 0.015" off lands. It has hinged bdl bottom metal which appear to support that length but will require more powder to get desired velocities. Is there a point of diminshing returns for bullet jump vs chasing lands?

Also, for a hunting rifle what is the general consensus regarding test groups? I intend to shoot 3 and rest to allow barrel to cool. I want to simulate cold bore shots as much as possible. However, do most of you leave barrel fouled or should I clean between groups to simulate cold, clean bore?

I eventually want to switch to 215 berger hybrids and h1000 but was curious how they perform at shorter distances also (100 yards or so). Also, I may rebarrel to a bartlein or similar barrel after this season just so I know exact round count and prefer SS over the CM ER shaw on it now.

Sorry foe the length of my first official post and would appreciate any and all feedback/advice.

Thanks,
Dan

 

[MagnumManiac]

For hunting, I use 200gr Accubonds in my Kimber 8400 Select, I use RE25 @ 79gr in WW-Super brass. This is a hot load, but I have .150" of jump in this rifle with that combo at mag length. It is superbly accurate, giving me consistant .5 MoA groups to 800yrds.
I can't load the Bergers to mag length in this rifle, I have also used 190gr Nosler Comp bullets in this also, but only at gongs and 1 deer, performance on animals isn't great.
H1000 and Retumbo are good with 200gr+ bullets. I've never experienced problems running Alliant powders in warm weather, I work up my loads in summer with all powder types, never had a proble doing this, and yes, going from summer to winter DOES change POI slightly, but who doesn't check trajectory before hunting season anyway?!
My hunting rifles are clean most of the time, but if they don't show POI differences between squeaky clean and fouled, I will use them fouled up to about 40 rounds and clean. I shoot my groups with the barrel fouled, normally 2 fouler shots on a clean barrel before I start. I shoot my 3 shots fairly quick, not quick enough to cook the barrel, then I let it cool for the next 3, and so on. The barrel is warm, say the same as ambient when I start a group. I, also don't worry too much about seating depth until I find a good powder combo, then tweak seating depth.
My long range target/hunting rifle is single loaded, so it gets the seating depth set to start with, then shot for groups, it doesn't get cleaned for 200 rounds or more, it performs better with the carbon removed but the copper not scrubbed out. It's a completely different set of parameters to my hunting rifles, whether long range or not when developing loads for it.

Hope this helps you out.

Cheers.
gun)

 

[FEENIX]

Welcome to LRH and enjoy!

You will best to find the best compromise between your COAL and CBTO and Berger has an excellent article about it.

For .300 Win Mag loads, use custom search on the top right hand corner (this is your friend and will help you significantly in your queries), in particular LRH member BROZ's post.

Good luck!

Ed