7mm Weatherby Reloads at the Range, Take 2 (w/ chrono data)

[Dr. Vette]

for reference, here is a link to session #1 from 2 weeks ago:
viewtopic.php?f=4&t=20387&hilit=weatherby

Today I took 6 different loads to the range. Powder is H-1000, primers Federal 215M, brass once fired and neck sized with Redding S-bushing die.
Based on previous data and the nice 73.5 load I made loads at 73.4, 73.5, 73.6, and then 76.0. I also added a 73.5 and 76.0 at approximate magazine length, 0.055 longer than all other loads.

Loads were shot in round robin ascending order (one each then start over) for a total of 3 rounds each, except for the 73.5 Long which was last and out of order.

Chrono data in order (go down by column):

73.4: 3079, 3078, 3073
73.5: 3091, 3101, 3074
73.6: 3123, 3073, 3087
76.0: 3160, 3133, 3112
76.0 Long: 3160, 3212, 3192
73.5 Long: 3074, 3060, 3039

I think the chrono was probably accurate as my 7mm Rem factory load is published at 3020; I got 3010. That's a good correlation.

Targets attached below. Comments welcomed.

73.4:


73.5:


73.6:


76.0:


76.0 Long:


73.5 Long:

 

[Dr. Vette]

The 73.4 load seems to have some exceptional numbers on the chrono.
I was surprised a bit at the lack of velocity improvement jumping from the 73.X loads to 76.0. I suspect that even the 26 inch barrel can't burn all of the powder and the extra is going to waste.

Should I adjust OAL to improve accuracy of the 73.4 load? Swap to a different primer?
Other thoughts?

This is the first rifle I've ever attempted to handload for, so suggestions are welcome.

 

[FOTIS]

Start playing with seating depth. I had exceptional luck with retumbo

 

[Jimbeaux82]

I have done a little experimenting with H1000 in my 7 WEA and a 162 gr Hornady Interlock BT (not SST) bullet. I loaded up 74, 75, 76, 77 grs and shot thru a chrono. My barrel length is 24". Unfortunately, my chrono did not register with the 74,75 gr loads and I got 76 grs - 2984 fps, 77 grs - 2985 fps. I did not see any excessive pressure signs on the cases or primer but have seen when reaching max loads that velocity sometimes plateaus like this so I stopped. Groups were 1.25". I also worked up some 150 NBT loads for a buddy and got 78 grs, 3137 fps, 1.25" groups, no outward signs of excess pressure. I did not play around very much with seating depths.

 

[Dr. Vette]

Any additional thoughts?
Try below 73.4?

I'm probably going to be loading another set for a time at the range this weekend.

 

[Oldtrader3]

Try 73.5 grs, IMR 7828, published at 3210 fps and 53 KIPS? I use it in my 7mm Rem Mag and my .340 Bee and get published velocities in my .340 certainly, according to my IMR data sheet from Weatherby.

 

[OU812]

I like 76.0, good speed and a workable group. What was the shot order? 1-2 almost touching 3rd out or a different order?


Bill

 

[SJB358]

Yep, I am with Bill, 76 grains would be where I would work it. Even reshooting the EXACT load might show you a pattern. I would probably go shorter rather than longer though. 76 looks like a great load..

 

[Dr. Vette]

I like 76.0, good speed and a workable group. What was the shot order? 1-2 almost touching 3rd out or a different order?

Bill

Unfortunately I don't recall the order.

Yep, I am with Bill, 76 grains would be where I would work it. Even reshooting the EXACT load might show you a pattern. I would probably go shorter rather than longer though. 76 looks like a great load..

I can't go any shorter. I already have to tap the case to settle the powder and still get some compression.

Note that 73.5 looked like a great load 2 weeks ago:
download/file.php?id=2747&mode=view

Look at the top of this thread for this week's 73.5 and compare. If I might have pulled this week's 3rd shot, then it's probably an accurate load.

Questions -
Am I reading too much into the low ES of the 73.4 charge? One would think they'd walk into the same hole with that low of a spread. :grin:
And since I gained no appreciable speed going from 73.X to 76.0 am I still gaining anything by using more powder?

Thanks for your insights gents!

Patrick

 

[SJB358]

Patrick, focus there at 73.4 but sometimes the lowest ES doesn't equate to the most accurate load. Your barrel might like them somewhere else.

Have you tried a drop tube to get it all in there?

 

[OU812]

I like 76.0, good speed and a workable group. What was the shot order? 1-2 almost touching 3rd out or a different order?

Bill

Unfortunately I don't recall the order.

Yep, I am with Bill, 76 grains would be where I would work it. Even reshooting the EXACT load might show you a pattern. I would probably go shorter rather than longer though. 76 looks like a great load..

I can't go any shorter. I already have to tap the case to settle the powder and still get some compression.

Note that 73.5 looked like a great load 2 weeks ago:
download/file.php?id=2747&mode=view

Look at the top of this thread for this week's 73.5 and compare. If I might have pulled this week's 3rd shot, then it's probably an accurate load.

Questions -
Am I reading too much into the low ES of the 73.4 charge? One would think they'd walk into the same hole with that low of a spread. :grin:
And since I gained no appreciable speed going from 73.X to 76.0 am I still gaining anything by using more powder?

Thanks for your insights gents!

Patrick

IMO there is reason to burn more powder if the speed change from 73.5-76.0 is not enough to get excited about, but accuracy wise it might be worth it if the 73.5 does not pan out. Yes 73.5 does show promise as well and if you think you may have pulled the shot that is out I would give them another go that's for sure. I know for myself I do not shoot the exact same from range trip to range trip. Some days I can't miss other days I could not hit my azz with both hands.

Myself I don't pay much attention to the ES cause I'll never hold the gun in such an exact manner to make it count. Some of my best, accurate loads don't have the best ES.

Bill

 

[Dr. Vette]

Patrick, focus there at 73.4 but sometimes the lowest ES doesn't equate to the most accurate load. Your barrel might like them somewhere else.

Have you tried a drop tube to get it all in there?

OK, I'll keep looking. I have a plan in mind for tomorrow.

No, have not tried a drop tube. For the few loads I've done at higher capacities it hasn't been a big deal just to tap them a bit so the powder settles.

 

[SJB358]

Patrick, focus there at 73.4 but sometimes the lowest ES doesn't equate to the most accurate load. Your barrel might like them somewhere else.

Have you tried a drop tube to get it all in there?

OK, I'll keep looking. I have a plan in mind for tomorrow.

No, have not tried a drop tube. For the few loads I've done at higher capacities it hasn't been a big deal just to tap them a bit so the powder settles.

I use a 4-6" drop tube all the time and it seems to keep loads that would be compressed, a touch easier to load. I just got into the habit and prefer to not have to tap the case, since my fingers are too big and I tend to drop stuff too easily! :lol: