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300wm tuning help

There’s nothing wrong with working up loads at 100 yards. And I wish I had an indoor 100 yard range to work up loads: no wind to worry about. And I’ll bet the temperature is fairly stable, too. You’re lucky. Takes a lot of variables out of the equation. As far as should you go revisit the .060 jump, no one can possibly know if that is of any value. Or if any particular load, seating depth, primer, bullet type or manufacturer, etc., will work in your rifle. All anyone can tell you is what worked for them in their rifles, or their experiences with other rifles. Which will (most probably) not work in your rifle (sounds harsh, but it’s true). You just gotta keep working on loads until you hit on something, then refine it. Use a system. The Berger system works really well. Do the whole test, not just half way. Once you get it shooting well at 100 yards, then start measuring velocities and calculating spreads, etc., for shooting 1000 yards. Right now you’ve got about a month before elk season. Limit your range to no more than three or four hundred yards, and worry about 1000 yards next year. From what you’ve stated earlier, you’re in better shape than you think!
 
I was mainly questioning the validity of that .060 depth as it was in the middle of my second round of groups when I swapped to a bipod for .060 to finish up my tests. Between the bipod and the bench, .060 was consistent at .6 moa but I chafed it off as invalidating the other depths as those weren't shot off the bipod...so I went with the next best group of .010.

Before I run through it all again, I may go back and hit .060 with another 10 rounds...if it's not better than my .010, I'll run some CCI primers to test at .010.

I think either way, ya'll are right, while I'd like to mess with this rifle all winter if needed to dial it in, I'm soon gonna have to just take what I can get, run it out at range and just limit myself to what the rifle and my capabilities are at the moment. I'll finish fine tuning this winter before I work on my steel rifle, already looking forward to trying this process over again with a 6.5 SST...maybe I'm just a gluten for punishment.

It's been a fun learning process thus far and the advice is greatly appreciated. Will post up some results and if the stars alone, some pics of a nice bull.
 
FWIW,
My current 300wm barrel refers .095" jump.
185 Hybrid Target, RL25 and F215 primers in Winchester brass.
I always test seating depth, powder and primers for every barrel.
 
lightweight hunting magnums can be a handful to shoot accurately.

Get a solid 0.75 moa load and call it a day. In reality anything sub moa will do everything you need it to do.

Don't overthink it and keep it simple.

Quickload is not very good at predicting ideal bullet distance in relation to the lands.

QL is just another manual, but a fun one to play around with.

If the bullet bearing surface / bt junction is seated below the case shoulder / neck junction. I think standard FL die with the expander button will help avoid doughnuts. But if using bushing die it be best to inside neck ream/cut the doughnut.

I have barrels with too little freebore than desired and standard RCBS FL dies work perfectly.
 
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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

Regarding your opening comments, your reloading ideas and process are squared away. I am curious though, with the powder charges your running in the platform you described, what if any are your pressure signs? How flat are the primers, are there any ejector marks on the brass heads? Your photo indicates vertical issues. Its not always a neck tension issue. Sometimes, it is a position issue. I get the idea that attempting to emulate factory ammo velocities is a popular concept but sometime, it does not work for every barrel. You commented on the 73.0g load test with good results. Work your way up from that point. As for testing at 100 or 200 yards? No harm in that. In pefect conditions, that ?moa group at 100 is going to be the same at 600yd. The concept of " some bullets don't stabilize until longer distances" is BS. If that bullet leaves that barrel in a tragectory not concenrtic to the bore, it does not miraculously change direction and adjust its course. Conditions down range may do that but it does not automatically correct the accuracy on target. If it were true, then any shot-out barrel sending a de-stabilized bullet down range would auto correct to stabilize? In my history of tactical and competitive applications, I have yet to witness "stabilizing at longer range" distance from the muzzle. A 2moa group at 100 is a 2moa at 600 etc... Might I suggest exploring Hodgdon Retumbo powder as a possible alternative.
 
@coldboreshot Read an article a while back that certainly supports what you have just posted. They came to the conclusion that if your group is better at 300 or 400 yrds MOA wise than at 100, it is because you have, more than likely,a parallex problem at 100 yds.
 
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Coldbore...that is a great point. I have decided to run an OCW test this weekend, now that the brass has been fired twice.

I will post a pic of the primer at 77gr when I get home tomorrow...it isnt flat, but its definately not a mild load. The primers at 78.5 were flat, but they did not crater, and no change in bolt lift. Cant see ejector marks, it's a bighorn SR3 action.

Did some more reading on velocity nodes vs accuracy nodes, etc. I thought they were the same thing. For me, based on my crap math skills and probably incorrect understanding of the applicarion, I think a .25 moa group at 600 with an ES of say 25 is going to out shoot a .75 moa group with an ES of 10. So maybe finding that OCW accuracy node is more important for me to find and then try to work on ES with seating and primers (not to open that can of worms in this thread)

The goal isnt to have a 300wm that shoots 3000fps just because it sounds good, i'd happily take it at 2800 or so, the numbers done change that much, just a few more mils up, but if that's the more accurate load, I take it.

I just figured at a DA of 9k and an elevation of 7k here in CO, I'd expect it to be faster than most folks barrels...but then again, with only 99 rounds through it, it may have not sped up yet, or it may just be a slow barrel.
 
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@coldboreshot Read an article a while back that certainly supports what you have just posted. They came to the conclusion that if your group is better at 300 or 400 yrds MOA wise than at 100, it is because you have, more than likely,a parallex problem at 100 yds.


Good heads up Murray. I will check that out. Another viable concept.
 
. As for testing at 100 or 200 yards? No harm in that. In pefect conditions, that ?moa group at 100 is going to be the same at 600yd.
Explain to me why I recently had a 6.5x06AI load shoot literally one ragged hole at 100 yards open up to 1 M.O.A at 500 yards. Changing from a 215 to a 250 primer cut the vertical in half.
 
Coldbore...that is a great point. I have decided to run an OCW test this weekend, now that the brass has been fired twice.

I will post a pic of the primer at 77gr when I get home tomorrow...it isnt flat, but its definately not a mild load. The primers at 78.5 were flat, but they did not crater, and no change in bolt lift. Cant see ejector marks, it's a bighorn SR3 action.

Did some more reading on velocity nodes vs accuracy nodes, etc. I thought they were the same thing. For me, based on my crap math skills and probably incorrect understanding of the applicarion, I think a .25 moa group at 600 with an ES of say 25 is going to out shoot a .75 moa group with an ES of 10. So maybe finding that OCW accuracy node is more important for me to find and then try to work on ES with seating and primers (not to open that can of worms in this thread)

The goal isnt to have a 300wm that shoots 3000fps just because it sounds good, i'd happily take it at 2800 or so, the numbers done change that much, just a few more mils up, but if that's the more accurate load, I take it.

I just figured at a DA of 9k and an elevation of 7k here in CO, I'd expect it to be faster than most folks barrels...but then again, with only 99 rounds through it, it may have not sped up yet, or it may just be a slow barrel.


Ah young Jedi, understand well, you do. I'm suspecting, a reduction in powder charge may be your key (if you continue with the H1000. But may I add something additional...
I have been known on this website for a saying I developed after reading numerous similar threads, " Borescopes and Chronographs should come with psychological disclaimers". Stop chasing the numbers. Trust the results on paper. I only use the Magnetospeed to establish the average fps for ballistic program input. Others may have a different opinion but at least, a tin foil hat is not a part of MY reloading process.
 
Explain to me why I recently had a 6.5x06AI load shoot literally one ragged hole at 100 yards open up to 1 M.O.A at 500 yards. Changing from a 215 to a 250 primer cut the vertical in half.

Atmospheric conditions interaction. Inconsistent position, including body geometry and inconsistent trigger pulls. I'm going to go out on a limb and bet that if you shot down a 500-yard tunnel and the rifle was in a fixed rest, taking all variables out of the equation, I bet you'd see that same Moa at 500. I'm curious though what was the 215 primer doing at 100 yards versus the 250 primer.
 
My 6-47 Lapua match rifle too, shoots 1 hole at 100 yds but can also shoot tight groups inside an fclass X ring at 500 yards. ( In no-wind conditions).
 
I didnt test the 250 at 100. I always test my 100 yard loads at 500 anymore because this is not the first time this has happened. Not always has it happened. I switched back to the 215 just to verify and sure enough right back to the same vertical. I wished I still had the targets but it's obvious when you put them side by side the 250 was better.
Didnt think I needed to shoot the 250 at 100 sure looked like I had "the load" with the 215
Untill I stretched it out to 500.
 
I didnt test the 250 at 100. I always test my 100 yard loads at 500 anymore because this is not the first time this has happened. Not always has it happened. I switched back to the 215 just to verify and sure enough right back to the same vertical. I wished I still had the targets but it's obvious when you put them side by side the 250 was better.
Didnt think I needed to shoot the 250 at 100 sure looked like I had "the load" with the 215
Untill I stretched it out to 500.

For a hunting rifle, even a 5" group at 500 yards is still a handsome kill. In competition at 500 yards, that could be a clean at 200-?X.
 
I tried to recall the last time I watched a factory hunting rifle put 5 straight into 3" bull at 300 yards. We have a couple "open" range shoots a year and people show up for fun shoots, 100,300 bench,running deer. 3-9 scope, factory ammo, no flags, in the bull, very tough. Sub moa group at 300 yards, adjust scope and go hunting. Elk taste great, good luck.
 
Graphing out my targets from the OCW, will post that up soon.

Can someone give me a quick QC on my primers? Left to right these are 73.5 to 78 (in .5gr steps)....just want to make sure the higher pressure still looks ok

The pic with 4 is 76.5-7820190907_180533.jpg 20190907_180548.jpg
 

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Graph of OCW...disregard the scribbles...I haven't graphed anything since HS. Was ran with NO chrono on the barrel. Graph is showing center point of each 3 shot group, charge weight for group listed next to the point. Point of aim was the X.

Thinking 77-78 (pending those primers look fine). POI for the 3 charges was very similar (and flat) and the group sizes were .5-.75...beginning to think that's as good as I can shoot a 10lb 300wm.

Guessing that was my node, attached are some pics from before at the low end 77gr with .010 seating depth and today at 77gr and .060...not really sure what to make of the seating depths......the .060 seems to have less vertical and more uniform groups??

What next?
Seating depth test at 77.5
Or primer change at 77.5

Chrono today on 4 @ 77.5 was
ES 22
SD 9.7
Ave 2981


20190907_201043.jpg 20190907_201245.jpg 20190907_201323.jpg
 
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You're onto something between 77 and 78 with the 0.060" jump

Next you can do one of 2 things...

Either load 20 rounds...

5 @ 77.0 gr
5 @ 77.3
5 @ 77.6
5 @ 77.9

and shoot them to see their POI and group size at 200 or 300 yards... or...

Do a seating depth test with any charge weight between 77 and 78 gr (I'd go with 77.2 just cause no reason) and test them for group size at 100 or 200 yards with...

0.010" In the lands
0.030" jump
0.060" jump
0.090" jump
 
I've already kinda run the seating depth test during fire forming. 010, .060, and .100 all shot well. .100 jump us a little short, and .060 seemed to group better than .010 with almost identical ES at 77.5

I think I'll do as you suggest and work a few .3's around the middle of that node...and try out CCIs as well, seems like a primer change from 215s to CCI or Vice versa can really hell the ES/groups. Hoping they tighten things up just a bit and I'll be happy. Plan to stretch the load out next weekend to see how it shoots at 600-800 yards.

Also, big thanks for the quickload data...got pretty close with that high node.
 
What should I do? I loaded 10 .300 win. mags. with CCI BR2 primers by accident I was using Winchester Large Rifle Magnum primers. Do I need to pull the bullets or could I shot them?
Hornady brass
IMR 4831 74 grains
Nosler Accubond 180 gr.
 

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