I've been tinkering with reduced loads with jacketed bullets for a while in various calibers, mostly using Clays and Unique. Today I tried Blue Dot in the 7-08 and had superb results using your data. I didn't set up the chrono, but the grouping was excellent and deserves more experimenting on my part. No signs of problems from 20-24 grains with a CCI 250 Magnum primer. Have you chrono'd your loads in vastly differing temps to see if the Blue Dot seems at all temperature sensitive in these reduced loads and applications? I'm considering using it this winter as a short range deer gun, but don't know what to expect in the cold temps. Keep those reports coming! Thanks for your efforts!

284:

I use to live in Minnesota and there gives a real opportunity to see how something performs in cold temps...

Blue Dot is quickly ignited being a fast powder so I really don't think you gain anything with magnum primers...

I now live in Oregon and in the low 30s or upper 20s is about all the low temp environment we have to deal with in SW Oregon during hunting season...

I went to college in New England and lived there for 7 yrs, so I am familiar with the Weather there.. Unless you are looking at Northern Vermont, New Hampshire or Interior of Maine, I would not be concerned about temp sensitivity....

My take on all of this Temperature Sensitivity stuff is that 99 % of it is Hog Wash Anyway.... I have hunted in 30 below in MN and I never had any problems with ammo nor did I know anyone else having problems with ammo...

I can see a potential of having problems with ammo in hot weather.. and that is stretching it... If you are working with a real hot load and tested it in cooler weather and then are out in 110 degrees and left ammo baking in the vehicle on the dashboard, then I have seen that present problems... I have not seen Blue Dot present problems in that environment with a 223 at least when it was loaded to max recommendations... 14.5 grains with a 46 grain HP bullet and being out at 105 degrees shooting prairie dogs in Montana....

for a note, my max recommendation in a 7/08 case is 22.5 grains of Blue Dot as a pressure limit.. I stretch that to 24 in a 7 x 57 case... 280 cases don't get by with much more...however I have noticed that a short fat case, like a 284 or a Short Mag case allows more Blue Dot before pressure signs show up than a longer and thinner case... IE: 284 vs 280.....

Once again the velocity gains are not worth pushing it beyond 24 or 25 grains... If more velocity were needed I would recommend going up to SR 4759, IMR 4227, or IMR 4198 ( considering reduced loads, with reduced recoil, was the desire)

Cheers and good luck...
seafire

Thanks for your reply. I checked back to the info I had downloaded that you had posted on the 7x57 and/or maybe 7-08 and the 140gr. bullets. My case capacity in the 7-08 was averaged for 10 cases at 40.2 grains, filled to the top. I do see where Roger had issues with the 120gr. crimped in the cannelure. I also see where you tried the 150gr. Rem. SP, and that shows lower charge weights as well. Perhaps I missed another post about your advising lowering the max charge weights with the 140's. Either way, the 23 and 24 gr. loads had the poorest groups (and even they were totally acceptable for a deer sized target), but no pressure signs that I could detect. Next step will be to chrono them and see what I'm getting.