Home Forums Reloading Big Game Rifles ES, extreme spread,

Ok, for anyone interested,

60.0 grains, avg 2803 SD 6 ES 12

60.5 grains, avg 2848 SD 14 ES 26

61.0 grains, avg 2852 SD 9 ES 18

61.5 grains, avg 2873 SD 8 ES 15

62.0 grains, avg 2886 SD 14 ES 26

62.5 grains, avg 2924 SD 5 ES 11

63.0 grains, avg 2940 SD 6 ES 13 this was the start of a 'sticky' bolt lift and we stopped.

.300 wsm, brand new barrel, starting all over, the factory barrel liked 65 grains of H4350 and a 165 grain SGK, it would shoot the TSX's, just never as well. In fact TSX's are never my most accurate bullet,,,might be time for a change.

runout according to my Sinclair gauge is usually .003-.005

Rifle is bedded, As stated earlier brand new barrel, (8 month wait) need to start all over, would be nice to have this rifle dialed in for Elk in 7 weeks.

Let me tell you, this hand-loading in pursuit of the ultimate groups can be a fools folly,

It never ends.....................

Pick the most accurate of the above loads and re-shoot it a couple-three times. If That load is still the most accurate of what you have, then move the seating depth up to .010 off the lands and start shooting groups again. Work back in .010 increments. When you find the right seating depth you should have an accurate load under 1 MOA. At that point you can try to fine tune the load by moving in .005 increments and trying 1 grain up and down in charge weight.

You can try whatever seating depth you want and whatever increments suit your fancy, but I have found doing this for a lot of rifles with Barnes bullets that method matters and is better than guessing. You may have to move back past .125 off to find what your rifle likes. I have a 25-06 that shoots 1.5-2.5 MOA at pressure but if I back that thing way off, down almost 300 FPS, it shoots well under MOA. Depending on the powder you use you may find similar problems to overcome.

OK, the 0.5gr step is a bit too big for that cartridge to reliably find nodes. There's almost certainly one between 60.5 and 62.0, but it's hard to tell where. If it was me I'd shoot four additional charge weights 60.3, 60.7, 61.2, and 61.7 and update your data. You're trying to find a spot where the velocity varies very little across a 0.5 or 0.6gr range, as that indicates a contracted bore is counteracting the extra pressure from the extra powder. You then set your charge weight to the center or slightly to the low end of that range on a low ES/SD point. Then tune for accuracy with seating depth.

That's bad. I would physically straighten those rounds, or get a new seater.

Learn to use velocity nodes, and it usually takes about 30-40 shots and you're done and getting basically what a given barrel and jacket's uniformity will allow you to get.

Appreciate the advice Bob.

again, like I said,

it never ends.........

Does your runout tool have a feature to straighten the rounds? If so that's an acceptable substitute if you get a decent feel for using it.

I have the Sinclair concentricity gauge, 90 bucks, not able to straighten with this particular unit, at times you almost need to be an octopus trying to hold everything in place for accurate numbers.

I will say my runout is almost equal with Nosler 'Custom Trophy Grade' factory ammo.

My issues at this time are bigger than just runout I believe,

New barrel, leave for a Elk hunt in weeks, and H4350 and TSX's have never been the best in the .300 or the 30'06

The '06 just loves IMR4350 and 150 SGK's, All out of IMR,

Tomorrow a lb each of IMR and R17 will be coming home,
That means we start all over again.........

It never ends.......

I will try that 60g to 62g suggestion you had earlier, Plenty of H4350 on hand.

What is the brand and length of the new barrel ?
Looks to be a little slow.

For what it’s worth. My model 70 EWS shoots the 168 TTSX sub moa all day every day.
Norma brass
F210M
65 or 65.5 grs RL17 ( 65 above 80 degrees).
-.050
3150 FPS. , 23 ES , 11 SD
Said rifle is long throated so I am able to load longer than saami.

Bartlein 24 inch, you say you like the 168, did you ever try the 165? Any diff?

I never get really serious about load development untill after the barrel speeds up, usually around 100 rounds.

I have not.
Damn near shot the barrel out working with 180 partitions . I hate a flirt !
Moved to the 168 TTSX and that’s where I’m at .

As a rule in general I completely agree, but when it comes to the 300 WSM all bets are off. Velocity has to been paid attention to.

Because of the case geometry (short, fat, minimal taper), cases can often be "sticky" depending on brass, sizing dies, chamber cut/finish, etc.

He's absolutely below max pressure with 63.5 H4350 and a 165 at 2,978.


To the OP, I could really care less about ES, and presuming a solid ES from 3 shots is mostly pointless. I want accuracy first, velocity second.

I've loaded for something like 8 300 WSM's going back 17 years. It's among the simplest rounds to make work.

H4350 or RL17 is your Huckleberry. I generally start with RL17, and it typically accepts 0.5 grains more than H4350. My "go to" loads in the 300 WSM have forever been a 180 gr. bullet over 64.0 H4350 or 64.5 RL17, for 2,980 and 3,030 fps respectively (24" bbls).

Try both standard and magnum primers. Some 300 WSM's prefer one over the other... it pays to try both.

My .02 this morning. I didn't read the thread so forgive me if I'm repeating what others have said...

appreciate it Brad, and all others also.