Primers can be hard to come by, so I snapped up some Winchester large rifle magnum primers. I know I'm ok using these for the 300 wm for my model 70. What about the 308 rounds for my ar10T?
I use varget and IMR 4895 close to max recommended loads in the Hornady manual. I use 168 gr amax and btsp.
Should I just decrease the powder to say half way between min and max loads and experiment from there for accuracy? Can't find anything that definitely says pressures will increase if the only change is going from LR to LR magnum primers.I really don't want to experience an exploding barrel!!(although it might make entertaining reading on this forum if I survive to tell the story) If I just use the 2000 primers I bought on the 300 wm reloads, I will never use them up.
Fox you generaly dont have to change anything on rifle loads but not true with pistols. If if makes you feel better those powders with the 168s will be ok on the max. There is a need to watch 4895. I load the 4895 with 42grs and the 168 for 90 plus deg days and stay on that load for these altoloaders year round so as not to forget. Mag primers work fine backed off 1 grain in the load. That is a safe way to do it. Varget will not have any issues on temp at all. I make the duplex loads for hot weather only. The bigest thing is to watch which powder your using because of the heat your biggest enemy. The worst thing is that the accuracy may fall off due to eratic fire on different sizes of flash holes. going from an .080 to a .081 will show up on paper with the mag primers. The biggest thing in loading that changes accuracy is the flash hole dia. We did a bunch of army test with the flash hole changes and the results were interesting. The best accuracy came from lighting the powder just behind the bullet by using cases with a flash tube. I am useing this on my PPCs and Dashers after all these years. Its liks cheating in a match. MSH
MSH.
I have been loading the IMR 4895 at 41grains already with the regular LR primers for the 168gr bullet, so I will just keep it at 41gr and see what happens when I use the magnum primers. Just getting ready to start loading some rounds with varget. Good info on the effects of heat with imr 4895. Thanks much
Fox you have no issues with your load you might find the IMR a little hotter than the Hodgon because there is 2% differance in the graphite coating. But you have done good nothing to worry about.MSH
For what it's worth, I tried CCI 250 primers with BL-C(2) to try to get better groups. I had 42 gr. behind 185 gr. Lapua D46's and saw an 80 fps gain over WLRs. The groups were no better. This AR10, a stainless barreled carbine, doesn't like BL-C(2).
My first batch with that powder I loaded at 41.9, I thought it abit lite compared to the factory ones as far as the recoil so I upper it to 43.5 with a 150 gr FMJ....am waiting to see how they shoot as soon as it gets nice....I use Remington LR primers....will be loading up some 168 gr MATCH BTHPs with 4064..in Hornady brass....it was suggested by Hornady...and for my replacement TAP loads, I am going with the 168 A-max with Reloader 15 and #34 CCI primers.....Haven't figured the loads yet....but will let you know...I hope. :lol:
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