New IMR Powders

Bruce Mc

Handloader
Oct 26, 2005
1,165
377
Made it out to the range this morning for a couple hours of shooting. I was trying out IMR 4166 in my Ruger #1.220 swift and 4451 in the Win 70 JOC .270 win.

First up was 56gr of 4451 with a 130 gr Partition. I shot a 1.5" group at 3050 fps. The second was the same set up with 57 grs of 4451. That shot 3124 fps and I got a 3/4" group. Std. Dev. was 6.5. Definitely some room for tinkering. The OAL was 3.320. I was using Win. cases and Fed 210 primer. On a plus side, I think I'm finally getting the knack of controlling this featherweight on the bench, my groups are becoming more consistent.

130_Partition_57gr_IMR_44511.jpg



I also tried 36, 37, and 38 grs of 4166 with a 50gr Nosler Ballistic Tip in the .220 swift Ruger #1. The 38 grs did pretty good at 1/2" and an average velocity of 3850 fps. Standard deviation was 21. The last shot of the three shot group went to 3870 fps while the first two were 3831 and 3847. I was using Hornady cases and Fed 210 primer.

Since there is little loading data available on these powders I'm just guessing at what kind of room I have to work with. I think I'm nearing max on the .270 and 4451 but I think I still have a bit of room in the 4166. I had to call Hodgdon tech support to get a starting spot for the powder as they have no published data on the swift.
 
These days are exciting times....... plenty of new powders to try.
Those loads look pretty good.

JD338
 
Excellent load work with great consistency. Looks as if the accuracy potential is very good.
 
Both powders are a small kernel, they're compact and pour easily. I'm hoping they'll prove to be as temperature insensitive as IMR claims.
 
Both powders are a small kernel, they're compact and pour easily. I'm hoping they'll prove to be as temperature insensitive as IMR claims. It was 80 degrees this morning, I think next time out I'll do the middle of the day and see how the velocity compares at 101.
 
I find if I support the grip with a sandbag as well as the but stock and use my left hand to hold the forend steady I can keep it from drifting about.
 
Bruce Mc":1c8ru0m9 said:
Made it out to the range this morning for a couple hours of shooting. I was trying out IMR 4166 in my Ruger #1.220 swift and 4451 in the Win 70 JOC .270 win.

First up was 56gr of 4451 with a 130 gr Partition. I shot a 1.5" group at 3050 fps. The second was the same set up with 57 grs of 4451. That shot 3124 fps and I got a 3/4" group. Std. Dev. was 6.5. Definitely some room for tinkering. The OAL was 3.320. I was using Win. cases and Fed 210 primer. On a plus side, I think I'm finally getting the knack of controlling this featherweight on the bench, my groups are becoming more consistent.

130_Partition_57gr_IMR_44511.jpg



I also tried 36, 37, and 38 grs of 4166 with a 50gr Nosler Ballistic Tip in the .220 swift Ruger #1. The 38 grs did pretty good at 1/2" and an average velocity of 3850 fps. Standard deviation was 21. The last shot of the three shot group went to 3870 fps while the first two were 3831 and 3847. I was using Hornady cases and Fed 210 primer.

Since there is little loading data available on these powders I'm just guessing at what kind of room I have to work with. I think I'm nearing max on the .270 and 4451 but I think I still have a bit of room in the 4166. I had to call Hodgdon tech support to get a starting spot for the powder as they have no published data on the swift.
> the group @ 3,124 says lets go hunting !!!!!
 
Yep, I loaded up ten rounds to check it out for consistency. I'm also gonna shoot it in the heat of the day and see how the temperature stability holds up.
 
Make sure to let the rounds and the rifle reach ambient temperature before doing the test.

Just throwing that out there.... As some people walk outside, fire the rounds, walk back in, and call it good..... Doesn't work that way, lol.
 
Ridgerunner665":2udvp3vh said:
Make sure to let the rounds and the rifle reach ambient temperature before doing the test.

Just throwing that out there.... As some people walk outside, fire the rounds, walk back in, and call it good..... Doesn't work that way, lol.

What's your procedure Lynn? I've never been bitten too much as I usually work up most loads in the spring around 50* but I'd like to try and experiment a little my different pet loads.
 
I just make sure to let the rifle and the ammo sit outside for at least a couple of hours... not in direct sunlight, as that will heat things well beyond ambient temperature.

If the rifle isn't at ambient temperature the results are flawed... As I'm sure you know... Steel expands when hot and contracts when cold... This effects the pressure curve.
 
Gotcha. Makes sense to me. Maybe this year I'll try and work
Them out a little in the cold. It's funny but one of my favorite powders is RL19 in the 338. It clocked 3050 with the 210 PT around 50-60* and that fall I took an elk a little over 400 yards at probably 15-20* with the same load. I'd love to see what I'm losing around the 30* mark. Maybe ignorance is bliss in this case.
 
At 400 the velocity difference can be pretty big and still go unnoticed on game...

But at 600 and beyond losing more than 50 fps (and not knowing it) can become a problem.

Not trying to belittle a 400 yard kill shot by any means.... Just saying that it takes a little further than that to notice.... Even losing 100 fps only changes the trajectory about an inch at 400... At 600 its 5 inches (depends on BC).
 
For sure Lynn. Makes complete sense to me. I'm a 600 and under guy and 500 and under is better yet for me. Still, I'd like to know the speeds and how much change there is.
 
Makes sense to me too. I'm more concerned with a max load becoming a problem load in extreme heat. I plan on working up to my load to see what variations might occur. I've loaded up ten rounds leading up to the 57gr load that I like. I'm not a long range shooter either but I am a tad obsessive about knowing exactly what my rifle is doing. Lynn, your input has been greatly appreciated and has cleared up several misconceptions I've had about ballistics. And the tutorial on barrel nodes was just fantastic.
 
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