7 LRM and alternative powders

Based on what you have on hand I know Retumbo will work (and work well), as will RL-25 (RL-25 tended to be a bit more temperature sensitive than H1000 or Retumbo). I suspect RL-33 will also do a decent job, not sure about RL-22.

Jeffvn
 
I burned a little bit of powder today with Azshooter, and luckily I was able to use his chronograph. I shot both Us 869 and Retumbo, the results were as follows:

80.5 gr US 869 averaged 2985, with an ES of only 5. (this is only two shots, the chrongraph did not register the first shot).
81 gr US 869 averaged 2989, ES of 20
81.5 gr US 869 averaged 3018, ES of 25
82 gr US 869 averaged 3051, with pressure starting to show, ES 33.

Retumbo.
69 Gr. Retumbo Averaged 2871, ES 27. Accurate load, two were in the same hole.
70 Gr. Retumbo Averaged 2910 ES 40, with good accuracy potential (triangle about at about an inch).
71 Gr. Retumbo Averaged (skipped 71 grains)
72 Gr. Retumbo Averaged 3003, ES 38 with good accuracy potential (triangle about at about an inch).

The first group was shot at about 80*, and final was shot up about 90*.

I like the accuracy potential of Retumbo, although those ES' are fairly high for shooting 700+. US 869 is definitely in the mix, showing accuracy potential, with good speed, although given the choice, I'd rather burn 10 grains less for similar speed, ES and accuracy.
 
Are you guys shooting the LRM concerned about the relatively low velocities? I get 2975- 3000 from my 7wsm with a 25" Brux.

I am wondering because I have one ordered, partially due to reading the marketing and hype that 3100 was easily obtainable with the 180's. I sure hope it's accurate....
 
I'm not going to lie, the fact that I will probably not Reach 3100 like I had thought I would is a little disappointing. But a high ballistic coefficient bullet at 2950 to 3000 is still pretty quick.
 
I wonder why my rifle is in line with what Gunwerks lists? The original hydro formed virgin brass I got from them was at a .020" setback in the shoulder. That first firing with 73.6grs of H1000, 215Mprimer, and a .020 bullet jump propelled the 180VLD to 3236fps...very slight pressure signs with 1/3MOA. The once fired brass with only .001" shoulder setback showed moderate pressure signs with the exact same components, so I ended up with 72.8grs being the sweet spot @ 3145fps.
 
I think I could probably squeeze 3100 out of it as US 869 was getting close at 82 grains. The velocity was starting to jump around with each shot being +/- 15-20 fps difference where the others were mostly within 5-10 for two of the shots, with one shot causing the ES to rise.

But, I'll shoot where the accuracy is. HOPEFULLY thats around 3000 as I kind of have a fetish with breaking the 300 fps barrier.

Sitting here looking over my notes, 82 grains of US 869 produced speeds of 3058, 3065 and 3032. I think I could achieve 3100 with this load. The accuracy potential is there, with this load being about an inch and a half, but in a triangle. I think with a little COAL work, this load could not only be fast, but also accurate, although I think it would wear out the brass a little quick as it is higher on the pressure scale. No stick bolt, or smileys, but a touch more recoil and the primers are starting to flatten out.
 
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