Hunterjohnb
Well-Known Member
Hello all, can I have your oponions on the use of magnum primers in non magnum calibers, when loaded with slower burning powders.Thanks in advance.
magnum primers will burn hotter and increase pressures in non magnum cases so reduce loads by 10% and work up again. Personally i would only use a magnum primer in a magnum caseHello all, can I have your oponions on the use of magnum primers in non magnum calibers, when loaded with slower burning powders.Thanks in advance.
Define magnum casemagnum primers will burn hotter and increase pressures in non magnum cases so reduce loads by 10% and work up again. Personally i would only use a magnum primer in a magnum case
So, when you dropped back by 10% to find a load for the magnum primers, I assume you ended up with a lesser powder weight than when you used conventional primers?reduce load by 10% and work up with magnum primers.
i use magnum primers with
100gn spbt in 243
150gn spbt in 308
250gn spbt in 338
they burn hotter and longer so they burn most of your powder but do look out for presure signs.
I am loading for a .270, for long range. The problem is my chrony reckons I have a high ES (approx. 70 fps) and SD. My groups are 3/4 MOA @ 700m with VLDs but there is obvious room for improvement according to my chrony. I am thorough with the brass prep (same brand and shot-life of brass, redding dies, primer pocket uniforming, flash hole uniforming, case trimming, case weighing, chamfering etc.) and so having come across someone's post of using magnums in non-magnum rounds to reduce ES / SD, I thought it was worth exploring. Plus, if what I hear is true, there may be a saving in powder as I can reduce the charge?yes you do end up with less powder and yes velocities are higher,you have to work the load up at .2 at a time and to watch for presure signs.
what cal are you loading?
use whats in the loading manual. speer recomends a magnum primer for imr 4350 in its 243 data and 243 is not a magnum load.if you use a magnum primer with this data it reduces group size by 25mm some powders need a hotter primer for good ignition.Hello all, can I have your oponions on the use of magnum primers in non magnum calibers, when loaded with slower burning powders.Thanks in advance.