300wm tuning help

[Vandy321]

300wm, berger 215s, Ferderal 215m...looking for help in tuning

Have run a charge weight ladder, found a node (76.5-77.5) at .020 jump.

Loaded up 77gr and did seating depth from .010 - .040...went with. 010, but .030 look ok too. About .4-.5 MOA at 300 yards between the two. .020 was .75 MOA.

Went back, loaded up groups at 76.8, 77, 77.2 and seated at .010....groups sucked, .75 at best (77 was spot on horizontally, but string out to .75 moa in the vertical indoors at 100 yards.

I'm questioning my neck tension.

Loaded round is .335, (so .0135 necks) I measure them at about 013.

I use a reddding bushing die (no expander ball) to compress down to .331 and expand out with a .306 mandrel. With springback I have what. 0025 neck tension?

I have a .332 bushing, a .331 bushing and expander mandrels in .3055, .306, .307

Not sure which combo to try...reading some 300wm's like a little more tension?

Suggestions on what to load next? Should try closer to the lands at .005 jump next or try another combo of neck tension? Maybe go with the .307 mandrel for just over .0015 tension after springback?

Seems from reading the forums, alot of rifles typically shoot lower ES with lower neck.

 

[Murray Brook]

Check out Berger's seating depth procedure. I was having trouble finding a load for my 7mm/08 and in my research I found the depth test on the berger site. Turned out I got the accuracy I was looking for at .120 jump. That's big and I would have never gone that far had it not been for the Berger test.
https://bergerbullets.com/vld-making-shoot/

 

[Vandy321]

I did, problem is, I run out of throat. At 77gr, middle of my node, I'm at a slightly compressed load.

I did a seating depth test during fire forming and really nothing jumped off the paper as the clear winner....020 and. 060 were the best groups. Seeing hybrids typically like closer, I went with. 010, .020,.030 and .040 today.

 

[Zero333]

When I do load development and right off the bat aren't getting close to my desired accuracy, I try a different powder.

RL-25 is always accurate in my 300winmags. H-4831 is accurate as well but it's best for up to 200 grainers.
Never got around to trying RL-26 even tho I got 2 lbs sitting around for a while.

Viht-N-165 / 560 / 565 will not disappoint either.

I also use RL-33 in a 300win but with 240 SMK. If you have lots of freebore to keep those 215's from invading powder space, I'm sure RL-33 would work nicely. I found data from Alliant with RL-33 and 220 SMK in the 300win. Max was 79.??... Can't remember, but I'll check when I get home. I have bookmarked a link to Alliant's manual in PDF.
They don't show this load on their site, among many others in the PDF.

 

[Ol’ Ed]

Murray’s and Zero’s advice is spot on. I’ll only add that I was developing a load for a friend’s .300 WM a while back and just couldn’t get it to shoot anywhere near what we thought it was capable of. On a whim, (or out of frustration, really) I loaded the most accurate group he had, but switched from the Fed 215 primers to the CCI 250’s and the group really tightened up a lot. That was an “I’ll be danged” moment for me.

 

[Zero333]

Murray’s and Zero’s advice is spot on. I’ll only add that I was developing a load for a friend’s .300 WM a while back and just couldn’t get it to shoot anywhere near what we thought it was capable of. On a whim, (or out of frustration, really) I loaded the most accurate group he had, but switched from the Fed 215 primers to the CCI 250’s and the group really tightened up a lot. That was an “I’ll be danged” moment for me.

I had the same thing happen with a 300win load, but backwards.
I was ok with the accuracy using cci250's, but loaded some with 215m to try and the group's shrank in half !!!
That was with 208amax & Retumbo.

 

[Ol’ Ed]

That’s funny. You just can’t talk in “absolutes” when it comes to rifles and load development. The best advice, I’ve found, is to keep trying and then, when all things fail, rebarrel and move on!

 

[coldboreshot]

300wm, berger 215s, Ferderal 215m...looking for help in tuning

Have run a charge weight ladder, found a node (76.5-77.5) at .020 jump.

Loaded up 77gr and did seating depth from .010 - .040...went with. 010, but .030 look ok too. About .4-.5 MOA at 300 yards between the two. .020 was .75 MOA.

Went back, loaded up groups at 76.8, 77, 77.2 and seated at .010....groups sucked, .75 at best (77 was spot on horizontally, but string out to .75 moa in the vertical indoors at 100 yards.

I'm questioning my neck tension.

Loaded round is .335, (so .0135 necks) I measure them at about 013.

I use a reddding bushing die (no expander ball) to compress down to .331 and expand out with a .306 mandrel. With springback I have what. 0025 neck tension?

I have a .332 bushing, a .331 bushing and expander mandrels in .3055, .306, .307

Not sure which combo to try...reading some 300wm's like a little more tension?

Suggestions on what to load next? Should try closer to the lands at .005 jump next or try another combo of neck tension? Maybe go with the .307 mandrel for just over .0015 tension after springback?

Seems from reading the forums, alot of rifles typically shoot lower ES with lower neck.

If I may... A few details missing here, unless I read over the top of it, you do not indicate what powder you are using. What are the chambering dimensions, barrel type, twist rate, is it absolutely free-float and the general rifle platform description?
In one of my 300wm platforms I have a Rem700/Kreiger barreled action, 5R 26" 1-10tw. It was chambered in basic SAAMI spec dimensions. I use Hodg H1000 powder (74.0g), Winchester "Super brass, Same bullet, same primer. I seat .015" jam. I use the same principal, .002'" bushing under loaded round OD neck dimension. I get 2850 fps, SD in the high single digits and it shoots sub (1/2) MOA. I can jam 15 on and still have a good seating surface in the necks.

 

[coldboreshot]

I too, use the expander mandrel after neck sizing.

 

[coldboreshot]

For comparative purposes regarding Hybrids...I have a Panda Fclass 284 win which I run 180 Hybrids. In testing, I found, either .010" Jam or .060" Jump was the most accurate. Everything in between, the barrel was a tomato stick. A lot of folks are under the impression Hybrids are like Match Kings where jumping is essential. Others have found Hybrids work best jammed similar to VLDs. For this situation, when the erosion begins to open up considerably, then I may look at the .060" jump. Again, just comparative on the Hybrids.

 

[Vandy321]

If I may... A few details missing here, unless I read over the top of it, you do not indicate what powder you are using. What are the chambering dimensions, barrel type, twist rate, is it absolutely free-float and the general rifle platform description?
In one of my 300wm platforms I have a Rem700/Kreiger barreled action, 5R 26" 1-10tw. It was chambered in basic SAAMI spec dimensions. I use Hodg H1000 powder (74.0g), Winchester "Super brass, Same bullet, same primer. I seat .015" jam. I use the same principal, .002'" bushing under loaded round OD neck dimension. I get 2850 fps, SD in the high single digits and it shoots sub (1/2) MOA. I can jam 15 on and still have a good seating surface in the necks.

I should caveat that I am a novice reloader. But I've taken ever detail of brass prep and loading I can to the best of my ability and tried to mirror BR shooters techniques (necks cleaned/turned, primer pockets uniformed, flash hole debur, etc). I do not weight my brass or bullets though. Its ADG brass and H1000 powder.

Custon chamber, dont know the specs, asked to be able to load to 3.825 (max length for wyatts extended mag box)...I did not get that. I've got a max COAL of 3.585 with the hybrid and a CBTO touching of 2.801...I was slightly displeased, may have the smith throat it deeper.

Barrel is free float, bedded in a manners. Checked it with a dollar bill, nothing rubbing. 1:9 proof. 26", bighorn SR3.

I'll see if I can find come CCI primers. For now, should I load up a few dif seating depths at less neck tension? I'm pretty confident 77 is my flat spot based off chrono data, but may resort to a ladder test again if I cant figure this out. Need to run H1000 as I need the temp staleness of it, it's a hunting rifle that I'd like to stretch out to a mile on steel.

 

[Vandy321]

My ES at the flat spot (77) was 19...didnt test it at the 76.8 and 77.2, but 77 was still the most accurate load.

Last 5 round group with 77 had about .25 inch or horizontal string, but .75 in the vert

Not sure what I can doin my prep/loading to better that ES...will try CCI and also less neck tension

 

[Dgd6mm]

What's your set up like? Bipod, mechanical rest, rear bag, etc? You need your load to lay down horizontally. I love H1000 in some cartridges, but would probably try another powder also.

 

[Vandy321]

Bipod (slightly loaded, read bag (although I am looking for a slightly taller read bag)

I may go back and revisit another quick seating depth test .060 and .100 showed some decent results (initial seating test was only done during fire forming at 73g, so not sure if thar gives valid data.


I just went with the longest load that looked good (.010) as I didnt want a compressed load...but it's obviously not the best load. Although some of the bad grouping is easily on me as the shooter too.

Will lighten up the tension and try some additional depths. Really hoping to make H1000 work, I need it to be temp stable, live in CO, temps in 80s this mo th during load testing, and then 2nd week of Oct I'll be at 12k with this thing hunting elk and temps could be in the teens.

 

[Zero333]

Here is the Link to the Alliant load data PDF where I found RL-33 data in the 300winmag...
http://www.alliantpowder.com/resources/alliant/index.html

Alliant's data was spot on.
I ran the RL-33 load with 240 smk in Quickload, and the estimated velocity was off by about 100 fps / 3 gr. from actual velocity.

Food for thought... you can get a helluva more RL-33 in the case than you'd think possible.
In F.C. brass - COAL of 3.600" with the 208 Amax,. you can fit 82+ gr before the base of the bullet touches the powder !

 

[Vandy321]

I dont have any experience with quickload...while not a substitute for testing, do you think it could help find a seating depth for me since my data didnt provide much to go on?

I was going to go test .005 and .060 again at least. Wondering what quick load would say about my depths and powder charges.

Is the estimated time in barrel a decently accurate way to predict a good load?

Excuse the ignorance. If anybody is bored, in be thrilled if someone would run my data through the program? Happy to provide all the specifics if needed. May he something worth purchasing as a novice, if it works?

 

[Ol’ Ed]

Ok, I didn’t realize you were a novice. Nothing wrong with that, we were all beginners at one point, too. Having said this, you don’t need quickload. And as you’ve stated that this is a hunting rifle, you don’t need to load jam unless you just want to ruin a hunting trip (you go to unload your rifle, bullet sticks in lands, dumps powder down in your action, etc.). Not seeing your targets is really not making this any easier, either. On the plus side, you mentioned that it shot .4 to .5 moa at 300 yards. That’s pretty darned good! Then, later, the groups opened up. Did the conditions change (I.e. wind, temps, wind direction, equipment, etc). All has an impact. If I felt that my group was possibly influenced the second trip, I’d go back to the .010 off, 77 grain loads. I’d load three rounds .010 off, at 76 grains, three rounds .010 off at 77 grains, and three rounds at .010 off at 78 grains. 1/2 grain increments in the 300wm, in my experience, don’t show a lot. Shoot those and see what those look like. If they suck, repeat for the .030 off. If you’re still not happy, we hunt with 190 grain Bergers and the elk are just as dead. See how your rifle likes those, starting over with the Berger load development pointed out above by Murray Brook. Based on what you’re telling me, you’re not far off. .4 to .5 moa in a hunting rifle is pretty darned good, especially when you’re really concerned about “minute of elk”. Hate to see you wear out a barrel trying to obtain the possibly unobtainable. As always, YMMV.

 

[simo hayha]

Check entire gun again. I would open barrel channel alittle more.

Try reloader 33 and smk 220.

Sometimes the older match profile bullets are easier to get to shoot small.

 

[D.Stone]

My experience has been that 300 WM shoots really well with light neck tension, and about 20 thousandths off the lands. I doubt there is anything wrong with the rifle, but you can always take it apart and put it back together...sometimes that works for some reason. Make sure your action screws are tight...etc.

How well are you capable of shooting off of a bench? Have you tried moving the target further away? I have found there are some days where I cannot really group below .6 MOA...and I find more and more of these days happen when I am behind a magnum. Moving the target out further where you cannot see the bullet holes through the scope seems to help me when I am having one of my so-so days. The only load data I am getting at 100 yards is to get a rough estimate of what charge weight gives me what velocity, and then I will move out further...I think a lot of guys get caught up in chasing dime sized groups at 100...when they should have their attention focused down range.

My 300 WM loading stuff.

Norma Brass.
H1000.
215 Hybrids.
CCI Mag Primers.

I size the brass in an RCBS bushing die. I think the bushing I have is set up to provide .002 of neck tension...but its been so long that I don't check it anymore.

My go-to load is 78 grains of H1000 behind a Berger Hybrid. I would suspect that you would find a good load around 75-76 grains with the ADG brass because you have a chamber that is similar to mine it seems like. At 100 yards, on any given day, I can put around 5 shots into 1/2 to 3/4 MOA...I have very few 1/4 MOA groups to show for all of the shooting I do. That same load has also out-shot plenty of competitors at extremely long ranges in the hands of myself and another person.

I think there might be an element of truth to the old idea that the bullet "goes to sleep" in it's first bit of travel...or rather that a lot of shooters tend to do better at distance when the sub-conscious "small group monkey" isn't messing with their marksmanship.

 

[Vandy321]

I neglected to mention that during seating depth test when fire forming at 73 grains I did have 2 groups shoot at .6 moa. It was a compressed load though in new brass at 73gr. So I went with the longer depth that shot decent .010

Now that its fire formed (shot twice) is it worth revisiting that .060 jump with 10 rounds of Federal and 10 rounds of CCI primers now that I have some more case capaxity??

I am sometimes forced to go to the 100 yard indoor just based on time vs the 2 hour drive to the long range. But I think I should at least be able to my best seating depth at 100 if need be and then run it out at long range to verify?

I understand testing at longer ranges is ideal I dont always have that avail to me when I'm free to go shoot