Load Development Sanity Check

[bob_dobalina]

I got some load data from Barnes and plan to work up a load for my 300 WSM with RL17. I've never used a chrono before but have one coming tomorrow - a ProChrono PAL. Anyways here is their data which I've tried to match exactly as far as components.

180 gr TTSX BT
Primer Remington 9 1/2M
COAL - 2.830"
Reloder 17
Starting Load 59.4 grains 2753 FPS
Max Load 66 grains 3081 FPS

I even seated to the same COAL. The only difference is the data stated a 1:10" twist rate and my gun has a 1:11" twist; interestingly the box the bullets came in state to use with an 1:11" twist or greater.

The load data seems to match Alliant's load data of max load of 66 grains, and a 10% reduction for a starting load, and is a cooler primer that Alliant recommended.

Anyways, I loaded one of each of the following charges - 60, 61, 62, 63, 64, 64.5, 65.5, and 66.

I plan to shoot from 60 to 66 watching for pressure signs along the way, and stopping short of the max load velocity of 3081FPS. My thoughts are staying below max velocity should keep me below max pressure. Does this seem like a safe an reasonable plan?

AccuBond is my go to bullet but I wanted to play around a little and I feel better having some actual data - I emailed nosler a year ago about RL17 and nothing but I should check back.

 

[DrMike]

The chrono will be a bonus to your shooting. I don't make as many sets when I'm working up a new load. A 2% variation will give you about all the data you need. The R9.5M primer is relatively cool, but it will work quite well in your 300WSM due to the shorter powder column. You should find a fine load lurking in your sets.

 

[bob_dobalina]

Thanks - ya probably overkill. I've already worked up to 62 grains of RL17 with Accubonds and WLR primers so the lighter loads this time weren't necessary. But, I'll get to play with my chrono! I'll work on some groups once I get a better handle on how these are doing.

 

[kraky1]

Years ago I did a load work up for a friend who bought a new xbolt and was going on a trip of a lifetime to AK for a guided moose hunt. WE started by shooting some federal /nosler Partition 165's in his 300 wsm. They clocked 3120 and actually showed some signs of pressure. So....I figured that was gonna be our stopping point and we chose the 168 ttsx as a "plenty good" for the wsm bullet. We worked up to 65.7 re17 and it was clocking 3110 with absolutely no signs of pressure and primer pockets stayed good for many reloadings. QL seemed spot on in this case saying that this was likely generating about 3100 at 61k pressure.
Accuracy was fantastic in his gun. We had groups nibbling at 1" at 200 yds. A 3006 auto was the gun he had used for many years and the new package was a little intimidating for him to start. After 3 range sessions he was dialed in and my 73 year old friend shot a group at 300 yds off a bipod that made me pretty green with envy. It all paid off cause he got a really nice moose and carribou on that hunt. He took the moose at about 350 yds with a pretty good downhill shot. He spined it and recovered the bullet in the brisket and it looked like a barnes ad.....4 perfect pedals.
A 180 ttsx is a "more than needed " bullet for the wsm but if its accurate who cares?
Good luck with your work up...I"m thinking 66 grains is a little ambitious for a 180 but the data seems to say its ok. Every gun is different and that chrono will be a great guide.

 

[Oldtrader3]

It probably doesn't equate 100% but I used 66.0 grains of IMR4350 with 180 Partitions in my .300 WSM. I got 3130 fps with no high pressure signs in my Browning Medallion.

 

[wildgene]

...I've tried the 175gr. VLD's, 180gr. AB's, HotCor SBT's, GrandSlams, SGK's, SMK's w/ RL-17. All showed best accuracy @ max (66gr.) or near max loads, w/ MV's of 3050-3090fps from my T3 Lite. I haven't found RL-17 any more temp. sensitive than the Hodgdon Extreme powders, & I do a lot of load developement in "cooler temps...

 

[DrMike]

When, oh when, oh when is all this foolishness about "selfies" going to cease. Gene, you're doing it all wrong. You're not supposed to see the camera. :?

 

[bob_dobalina]

Interesting results. Chrono issues?

 

[bob_dobalina]

Years ago I did a load work up for a friend who bought a new xbolt and was going on a trip of a lifetime to AK for a guided moose hunt. WE started by shooting some federal /nosler Partition 165's in his 300 wsm. They clocked 3120 and actually showed some signs of pressure. So....I figured that was gonna be our stopping point and we chose the 168 ttsx as a "plenty good" for the wsm bullet. We worked up to 65.7 re17 and it was clocking 3110 with absolutely no signs of pressure and primer pockets stayed good for many reloadings. QL seemed spot on in this case saying that this was likely generating about 3100 at 61k pressure.
Accuracy was fantastic in his gun. We had groups nibbling at 1" at 200 yds. A 3006 auto was the gun he had used for many years and the new package was a little intimidating for him to start. After 3 range sessions he was dialed in and my 73 year old friend shot a group at 300 yds off a bipod that made me pretty green with envy. It all paid off cause he got a really nice moose and carribou on that hunt. He took the moose at about 350 yds with a pretty good downhill shot. He spined it and recovered the bullet in the brisket and it looked like a barnes ad.....4 perfect pedals.
A 180 ttsx is a "more than needed " bullet for the wsm but if its accurate who cares?
Good luck with your work up...I"m thinking 66 grains is a little ambitious for a 180 but the data seems to say its ok. Every gun is different and that chrono will be a great guide.

cool story!

 

[bob_dobalina]

I have to think the last 2 readings (65.5 and 66) were incorrect. Hopefully this doesn't happen too often with the chrono

After these shots - I shot 62 gr RL17 with an 180 Accoubond after this and it clocked 2807,
and then 65.5 gr RL19 with a 150 gr Hornady Interbond clocked 2749fps.


I'm no expert at pressure signs, but the primers looked OK to me. They only thing I noticed was a ridge on the bottom of the shell, but I believe I always get this, and these shells were fired once before. It is a definite ridge you can feel with your finger though. Sorry for the bad pics - best I could do with my phone.

Now where do I start? I think I might see how 65gr groups, and try a few more readings with 65.5gr and 66gr.

 

[SJB358]

You looks fine to me, your speeds look right on point as well.

Shoot for accuracy and see what comes outta the woodwork. I'd be plenty happy with 2950 or so out of the 180.

My use of RL17 has echoed Gene's. You have some excellent numbers, looking forward to seeing what the groups look like.

 

[DrMike]

Your last two readings are not necessarily in error; you've maxed out and velocity is dropping. This phenomenon is somewhat common as the pressure curve begins to max out. There is not a strict correlation between pressure and velocity, especially throughout the defined curve.

 

[Oldtrader3]

Ditto to DrMike. Plus, I see an ejector shiny spot on the bottom of your case.

 

[hubcap]

I agree with Dr. Mike too. Once you reach rifle max adding powder causes velocity to go all over the place. I like the looks of 64.5 because that is the last charge that showed a nice jump in velocity. I believe the chrony is telling the truth.

 

[kraky]

Fwiw...here's the best "wallet group" I think I've ever shot. You know the one you show your buddies over a beer...or 6!
Anyhow the sad news is its only clocking about 2950 out of my tikka 300 win. But do I care.....not really. I'm 6'1" and it kicks like heck being with a light wt scope the gun only weighs as much as a bare marlin 3030.
As good of jacket as the newer bt's have....good BC...I think I'm good to go for most any realstic hunting anywhere....at least for a guy from brush country in northern Wis!

 

[DrMike]

That is certainly a great "wallet group." I believe that is about all I get out of my own 300 WSMs, but each has killed animals as if they were smote with the hammer of Thor, and each manages to do so with boring regularity. I'm content.

 

[bob_dobalina]

I wanted to report back - I went with hubcaps advice and tried to get 64.5 grains grouping. First 3 shot group at 100 was ok, I used it to adjust my scope, second group at 100 had 2 shots touching and one out of the group a bit, but where it should be. Then I put a target at 200, and really took my time and let the barrel cool, and put 2 shots touching - well almost - in the bullseye. Third, and last bullet, would not chamber. So there went my perfect 3 shot group! But good enough for me for hunting season.

This was the 3rd time I've had a shell not chamber in this gun, and I suspected it wouldn't from the previous 2. There is ever so slightly a bell below the shoulder of the case. Well, now I just loaded up 10 rounds, and 7 would not chamber. I've never experienced this before. I'm thinking a combination of not using enough case lube and the ridged TTSX bullets? It is definitely frustating.

Here's a pic of the 2 shot group, and the belled cases - you can barely see the light between them and the far left one you can see the bell pretty good -any suggestions?!

 

[DrMike]

It looks as if you are engaging the neck with your die. Perhaps your neck is slightly thickened or long. However, when you witness such belling, it is almost always due to pressing the neck back, especially when seating the bullet.

 

[bob_dobalina]

Do you think my die is adjusted incorrectly? I was 3/4 turn off of touching the die holder at fully raised, I switched to 1 turn off and had no further issues with 8 more rounds, so hopefully that was the issue. Thanks

 

[DrMike]

Do you think my die is adjusted incorrectly? I was 3/4 turn off of touching the die holder at fully raised, I switched to 1 turn off and had no further issues with 8 more rounds, so hopefully that was the issue. Thanks

Yes, I would opine that you were pushing the neck back enough to bell the brass.