New IMR powders

[wildcat westerner]

Hello,
I have hear very good things about these new IMR powders in terms of velocity gains and also copper fouling reduction. I have been told that a .300 WSM increase in velocity will place it in the 30-378 category with heavy hunting bullets.

Suddenly thse powders could seemingly resurrected a wildcat I designed. Many years ago I discovered that you could fill the magazine of a Savage rifle with four 9.3 x 64 RWS cases. These were large cases, without a belt, larger in diameter than .284 cases and 2.5 inches long. I designed a wildcat on this case necked to .30 caliber and had the base of the cases turned so they would fit a .30-06 bolt face. Dave Kiff helped in the design. Subsequently I found that this cartridge could nearly equal .300 Weatherby PUBLISHED ballistics. Pretty incredible in terms of the size differences in the cases. I noted the RWS brass was so tough it took three reloading to form these cases properly. As time went by I replaced my old cases with new RWS cases and found the cases were not made of the same materials in that I blew primers in loads four grains under my old maximums. The loss in velcoity was significant.
Now, with these new IMR powders I can see renewed life in my old wildcat. I would like to know has anyone done any testing with this newest. slowest of powders in a .30 caliber cartridge with aproximately 69-73 grains of powder with a 180 grain bullet?
Thank you for your attention in this matter.
Gene So

 

[RockyMtnMT]

Played with the 7977 a bit in bigger cartridges and it proved to be too fast and pressured too soon. So I can't help you much there. I have my doubts about a 300 wsm equaling a 30-378 with any bullet but I will be watching this thread closely to see what can be learned.


Steve

 

[wildcat westerner]

Hello Steve, Thanks for your reply and I assume from your answer, you have some large capacity cases, not near 69-72 grains. The man who informed me about this newer IMR powder put the 747 in the air and kept it up there. His physics, based on aerodynamics and ballistics is far superior to mine which is based on the human anatomy. Dr. Paul is as dedicated to first shot, unknown distance accurate shooting as any person I know, and I take his observations "to the bank." I do not own a .300WSM, but have a friend who does and you can be sure that we will be testing 7977 in it.
Thank You,

Gene So

 

[Radhimself]

whatever your smoking.... is good stuff

 

[Rich Coyle]

gene solyntjes,

I have a 9.3X64 wildcat also. It is necked to 6.5mm. It holds about three grains more water than a .264 Win Mag. I fired bullets up to 142 grains. You might try RL25, RL26, RL33 and IMR7828.

 

[bigedp51]

The latest 2015 Hodgdons Annual Reload Manual (magazine) tested the new powders and has loading data for the .300 Winchester Magnum and .300 RUM with 7977 powder. What got me is all three of these new powders are double base powders. The article states that 7977 is close to H1000 in burning rate.

Hodgdon 2015 Annual Manual Features 5000+ Loads

http://bulletin.accurateshooter.com/2014/12/hodgdon-2015-annual-manual-features-5000-loads/

 

[wildcat westerner]

Hello. Its a pleasure to contact someone with this case as a basis for a wildcat. I assume you are using RWS brass. Is this correct? MY original RWS brass was so tough it took 3 firing to get it properly fireformed and I was able to establish .300 Weatherby PUBLISHED ballistics with this smaller case.
Subsequent RWS brass fireformed on the first shot and blew primers a full four grains under my former loads. Have you had the same experience? Your wildcat must produce pretty high velocities.
Thanks,
Gene So

 

[Rich Coyle]

7/6/15 The temp went from 70 degrees to 73 degrees. I waited a few minutes between each shot.
I fired four loads with IMR7828 pushing Nosler ABLR 129 @ 3.405". The velocities follow.
68.0 – 3,395
69.0 – 3,434
69.5 – 3,391
70.0 – 3,482
71.0 – 3,525 tight action


8/17/15 64 degrees
Tried some RL26 at 300 yards. The loads consisted of Federal 215 Magnum, AB130 @ 2.885". The velocities follow:
60 – 3,107
61 – 3,083
62 – 3,110
63 – 3,139
64 – 3,206
65 – 3,237
66 – 3,285
67 – 3,309
68 – 3,351
69 – 3,409
There was no noticeable node.

8/17/15 66 degrees - 73 degrees
Tried some Barnes 127 LRX @ 2.771" at 300 yards. The primer was CCI 250 Magnum. The powder was RL25. The velocities follow:
68.5 – 3,289
69.0 – 3,331
69.5 – 3,357
70.0 – 3,372
70.5 – 3,386
71.0 – 3,416
71.5 – 3,442
72.0 – 3,482
Shots numbers 1,2,3 made a group of 5 ½". Near the center of this group shots numbers 4,5,6 made a group of ¾". Since I thought load number 6 was about maximum I made a 13 click adjustment to get shots 7 and 8 near the point of aim.

 

[Jcub]

There is no way a case loaded with 74 gr of powder will ever equal 1 that uses more than 100. Doesn't matter who your buddy is, he's wrong.

 

[Okanogan]

My experience with 7977 in 300 WM matches RockyMtnMT: too hot too fast resulting in over pressure signs before getting the velocity I wanted with 190 VLDs.

 

[Varmint Hunter]

Certainly doesn't seem possible to boost a 300WSM to 30-378Wby ballistics with a powder change. The new powders don't even claim to be velocity boosters.

Here is my limited experience with a new IMR powder:

I've been working with 7977 and 175gr bullets in the 7WSM. I get speeds no greater then obtainable with IMR 7828 or H1000 but accuracy is coming together with load development. I'm happy enough to get an accurate load with reduced copper fouling and is temperature stable to boot.

Either way - good luck. Sometimes modern advancements come from unexpected places.

 

[wildcat westerner]

Re: New IMR powders-reply

Hello,

Thanks for your replies. Thank you jCub for you reply which closely mimics applied physics. Logically a 25% larger case should be able to have higher velocities, than a smaller case. I look at some of these huge cases used to attain a small increase in velocity and it seems ridiculous to me from a period some years ago. As a writer for Precision Shooting, we did an experiment with Savages' help. A .460 Weatherby was necked down to .22 and loads such as 120 grains of powder behind a 55 gr. bullet produced 5,016 fps, and 6 3/8" throat erosion with just 78 rounds fired. A 6/284 of mine with a Krieger 32 inch barrel produced 3,564 fps with 107 gr. Sierras. That throat lasted just 400 rounds.

So, it would seem you"cannot get something for nothing". However, if you can gain the same velocity no matter the temperature varience, with reduced copper fouling, that is a huge leap forward to me.
Thank you,

Gene

 

[hembrook]

Interested in the .300 wildcat based on the 9.3x64, as I have one myself.

 

[Rich Coyle]

Interested in the .300 wildcat based on the 9.3x64, as I have one myself.

I have a wildcat 6.5mm based on that case. It matches the .264 Win Mag. Therefore I suppose your wildcat would match the .30-338 Win Mag.