Home Forums Hunting & Shooting Ask The Gunwriters "Non linear results"

J Barsness mentioned the excellent results he was getting with 200 gr bullets(comparable to 180 gr) in the 300WM, followed by other comments noting the performance of 150 grain bullets over RL26 out of the 270 Winchester, ie velocities matching 130gr bullets, combined with accuracy and acceptable pressure.
I recently took time to read many of the articles in a blog called "knowledgebase" written by a guy from New Zealand that also noted this phenomena and used the term "non linear results".
Due to MuleDeers credibility, I began trialing 200 Gr Partitons in my 300WM, after shooting 180's. Loaded up some 150gr Partitions in my 270's, after decades of happily using 130's.
IN both cases, I used RL26 and accuracy has been really superb, so I will continue work with the recipes. This mean shooting at longer range and over my chronograph.
I am wondering if this phenomena is limited to overbore cartridges?
I have (historically) prescribed to the theory that certain velocities, as proven by my chronograph, indicated a safe load. 3,000+fps with a 200 gr out of a 300 WM and 150's out of a 270, safely, are shifting the paradigm. But, the result speak for themselves.
Does RL26, in these examples, shift the pressure curve, making this performance safe?
Finally, I haven't read of anyone bumping into any problems, dangerous or otherwise, using RL26. Thoughts?

Reloder 26 flattens the pressure curve, because of being even more "progressive" burning than most other modern rifle powders. The powder starts burning very slowly, then the burn-rate speeds up as the bullet moves through the barrel.

There were already a number of powders that safely achieved 3000 fps with 200's in the .300 Winchester Magnum--but there weren't any that got 3000 with 150's in the .270 Winchester, except in 26" barrels. 26 will do it in a 22" barrel.

I've only played with 26 extensively in the 243, with bullets 95 to 105 grains. It has been surprising. Usually when I load up a charge ladder, I'll go a few steps above the max load, which in 243 means a couple grains. I don't generally end up shooting the last ones, as I see sufficient results before that, or run into pressure. That hasn't been the case with 26 in the 243. I've ended up shooting all of them, and generally picked a lower charge around the max for accuracy reasons. The only variance I have found in this is the 100 Partition, which got more and more accurate as I went up. I settled on 2 grains over Alliant's listed max. I still need to shoot these over a chronograph, but they shoot surprisingly well in a couple outings, and the cases don't seem stressed. I'm still leery though. Haven't decided yet whether to stick with that load. The chronograph will likely help me decide.

Strange powder. I need to try it in 30-06 next, with 200+gr bullets.

Have you checked it out in a 26" 270?

I sure wish the powder companies would print some better data for the 340 Weatherby. Yes, I understand that Weatherby chambers have freebore and one can’t control custom readers, but this Weatherby more than others seems to lag behind on data. I always thought of the 340/250gr as a medium bore parallel of the 270Win/150 grain combo. 3000 fps seemed like it should be there , but wasn’t until RL26 came on the scene. I know they are two very different cartridges, but wouldn’t it be neat if RL26 could do for the 340/250 grain partition what it did for the 270/150...

jaycee:

As much as I agree that more data is great, I'd pass the responsibility of generating load data to Weatherby's shoulders. Given the hundreds of possible configurations of chambers, throats, brass, and free bores, examining and pressure testing them all would near break a person. Send Weatherby a note and see if they'll get on the stick.

I don't know why more guys here don't use Quick Load as a reference. It indicates 26 is a/the top performer in many bottleneck cartridges.

It is great in the 340 and the 7 Mag and many more.

Will Re-25 do the same thing?

Many of us run Mac’s and quickload is almost ten years behind the technology train.

What is Mac's?

Thats a joke right . its a short barrel fully automatic pistol somewhat related to a MacIntosh computer, in that they have to rebooted several times a day.

Gain Twist powder!

Last Apple computer, or Apple product for that matter, that I owned was an Apple IIc (30+ years ago it was a fine computer that didn't have to boot off a floppy disk), so I guess I can't really relate to the difficulties Mac users face.

I hear you. The ol' 340 and 7MM Rem mag date back to '62. What internal ballistics software do the cool kids with Mac's use - for their 22 Nosler's I assume?

You gotta be kidding. My ten year old Mac Mini runs literally for months at a time without a reboot.