300 Weatherby ladder test

Dr. Vette · Sep 8, 2014

On Saturday we had a chance to get out and shoot Dad's 300 Weatherby with some new reloads. I set up some 200gr Barnes LRX bullets for him, as he is thrilled with the performance of the 150 TTSX out of his 7mm Wby rifle. The distance was 200 yards to the target, and Dad was shooting off from a front rest and rear sandbags.

Note the target and the speeds in the photos below.
I have no idea why the 83.0 is so low on the paper, and Dad swears he didn't pull that shot.

From what I see it looks like there may be a chance at a node at 83.5 to 84.0 grains. There were zero signs of pressure at that load, and I am tempted to try loading up 3 rounds each of 83.0/83.5/84.0/84.5 to see if an accuracy node shows up.

Does this sound reasonable, or would you have other suggestions?

Thanks!

JD338 · Sep 8, 2014

Patrick,

It does seem odd that 83.0 went low.
I think you are right on track.

JD338

SJB358 · Sep 8, 2014

Very cool stuff Patrick. Pretty interesting how they fell out. I would think your on the right track though.

I agree with Jim, it is odd how 83 went so low. Seems like with 83.5 and 84 being so close, you'd be in business. That load is smoking for a 200 grain bullet..

Dr. Vette · Sep 8, 2014

In years gone by, Dad has been the guy who could always pull off some really good shooting and amazing shots. Back in 2010 he took antelope at 500+ and 800+ yards using a ballistic reticle. However, now at age 71 1/2, I've seen his ability slip a bit over time depending on the day. So, who knows why the 83 did what it did. The guy who publishes the Optimal Charge info seems to indicate that a flyer right before a node is not unusual, so that may be what it is.

I will probably be the one shooting the next set, and we will see how it goes.
I checked every case and primer, and even lifted the bolt on 83.5 myself. No signs of overpressure at this point, which makes me think it would be safe to try 84.5. However, if any signs at that point then I know that 83.5-84.0 is the limit.

The goal is a 600 yard repeatable rifle. I would suspect that we are well on our way.
Earlier this year I bedded it into a thumbhole stock from Stocky's, and tuned the trigger to 2 pounds. It really is a nice rifle to shoot.

As I told Dad, I think I could throw together almost any charge and he could hunt with it next week, given that the whole group of 80.5 to 84.0 is about 3 inches in size, excluding the 83.0.

Patrick

FOTIS · Sep 8, 2014

I would be doing cartwheels!

Dr. Vette · Sep 8, 2014

FOTIS":akq0f9wh said:
I would be doing cartwheels!

Yeah, this one makes up for the shytte his 7mm put me through and my 270 is putting me through. Some days you get it right!

lhsako · Sep 9, 2014

Dr. Vette":2htgqr6z said:
FOTIS":2htgqr6z said:

I would be doing cartwheels!

Click to expand...

Yeah, this one makes up for the shytte his 7mm put me through and my 270 is putting me through. Some days you get it right!

so reloading can be frustrating?????.....lol :lol:

FOTIS · Sep 9, 2014

Patrick let us know how she groups.....

Dr. Vette · Sep 9, 2014

No problem. It may be a week or so based on my availablilty + weather. I'll probably get the loads assembled tomorrow.

Mud · Sep 9, 2014

I have been using IMR 7828 for my Weatherby and happy with the performance. Lately I started to test H1000.

How far are you seating your bullets.

Larry

Oldtrader3 · Sep 9, 2014

To me, it looks as though 83.0 to 84.0 is the place to start looking. The velocity jumps a little more at 84.0. That may be your max? Plus, the two shots with 83.0, 83.5 are really seeming to indicate a node?

longrangehunter · Sep 9, 2014

POI clearly shows 83.5; 84.0 but the velocity on 81.5; 82.0 are a lot closer then the 83.5 and 84.0 load for ES and SD. I'd look for a flattening of the velocity during an increase as the place to be........ but I could be wrong? Only testing further would revile the better load. When I see the velocity taper off while increasing powder charges that tends to be the node when I develop loads.

Dr. Vette · Sep 10, 2014

longrangehunter":fkgagxvy said:
POI clearly shows 83.5; 84.0 but the velocity on 81.5; 82.0 are a lot closer then the 83.5 and 84.0 load for ES and SD. I'd look for a flattening of the velocity during an increase as the place to be........ but I could be wrong? Only testing further would revile the better load. When I see the velocity taper off while increasing powder charges that tends to be the node when I develop loads.

I agree. Easy enough to add 81.5-82.0 in the mix for 3 shot groups.

The OCW guy told me once that nodes tend to happen about 3% apart with regard to powder weight. If so, that puts them right where I see them, and makes me wonder how accurate that 84.0 velocity really might be. I've found that sunlight gives falsely elevated speed readings with a chrono, and the 84.0 was the last shot of the morning.

More to come once I shoot the next round.

Patrick

Oldtrader3 · Sep 10, 2014

Patrick, ES and SD are not as important when there is a Degrees of Freedom issue with sample size, but you know that. You have a couple of points to start developing data with and clarity will come with further samples. Good luck with that.
Charlie

Dr. Vette · Sep 10, 2014

Mud":e7c2a6iv said:
I have been using IMR 7828 for my Weatherby and happy with the performance. Lately I started to test H1000.

How far are you seating your bullets.

Larry

COAL is 3.664, but I am measuring it as 3.000 to the ogive with my Hornady comparator.

longrangehunter · Sep 11, 2014

I looked back at the last cartridge I worked on (6.5x47 Lapua) and noticed very small ES and SD at 37.7 grains and yet the 37.4 produced the better group although the ES and SD where much higher...... so go figure?

On the other hand shot long range I did see variances in group POI from 300-600 yards that has now left me having to work up another load. Which is why low ES are so important if you're shooting LR.

Dr. Vette · Sep 12, 2014

The more I look at it the more I think I'll add 80.5/81.0/81.5 to my loaded groups of 3. It's not that much more time and effort to shoot those 9 at the range vs the time to go there and set up, etc. And, if there is a node there I'd like to see it.

If so, 3030 fps vs 3100 won't make any difference in the end.

baltz526 · Sep 13, 2014

81.5gr then work on OAL. 3000fps is plenty fast for a 200gr and will be easier on the brass. Brass life would be Important to me, As hard as some is to find and the cost of Weatherby brass.

Dr. Vette · Sep 13, 2014

baltz526":1jqm70l7 said:
81.5gr then work on OAL. 3000fps is plenty fast for a 200gr and will be easier on the brass. Brass life would be Important to me, As hard as some is to find and the cost of Weatherby brass.

I've got a fair amount of brass, so in the short term I'm not too worried about that.

I've loaded up both ends of the spectrum to see what works, but for less than 100fps I likely won't use a faster load.

Unlike Dad's 7mm Wby I suspect this will be only an occasionally used rifle, not his go-to rifle. As such, I would be somewhat less worried about barrel life and brass life should two different loads show to be accurate. The 7mm is loaded to its equivalent lower accuracy node, and as I mentioned to Dad recently the barrel should last quite a while.