I have a Juan Valdez custom 260AI with a short sporter barrel. I am shooting a compressed load of 4831SC under a 120 GMX and would like to squeak a little more velocity out of it, currently sitting at 2877. I know a few guys that got a significant increase out of their 7-08's by switching to a magnum primers. I am getting 1/2 MOA out to 500 so can't complain, but this is primarily a precision hunting rifle so would like a little more speed if I could get it. Anyone try magnum primers?
260AI with magnum primers.
- Thread starter fatboyz
- Start date
I think I would go to a faster powder before I tried magnum primers.
But maybe thats just because Ive had problems trying to use mag primers in smalls cases in the past.
- Location
- lloydminster
I found that while I was getting alittle more speed with a mag primer in my 308 I was hitting pressure spikes in mild weather temps. Went back to a match primer and haven't had any problems.
Like kona said try a faster powder. Your mag primer is mainly for a cold environment or large capacity cases.
Like kona said try a faster powder. Your mag primer is mainly for a cold environment or large capacity cases.
You may want to try RL 17. That's what I used at 42.8 gr pushing a 140 Berger Hunting VLD out of a 29" tube getting a "lazy" 2910 fps. The reason I say "lazy" is because I could have put more powder in but settled on this load as the speed was enough and accuracy 1/4 moa. I may have been able to go up to 45 grains + or - but never tried, I did go to 44 or 44.5 grains though.
I was using CCI BR2s but never thought of going to a magnum primer, I think the case capacity may be too small but hey, it may work. Only one way to find out. Oh, since you are at a compressed load, I would go down about 3-4 grains and work back up if you decide to try.
I was using CCI BR2s but never thought of going to a magnum primer, I think the case capacity may be too small but hey, it may work. Only one way to find out. Oh, since you are at a compressed load, I would go down about 3-4 grains and work back up if you decide to try.
ultimate_monkey
CGN Ultra frequent flyer
- Location
- victoria BC
skip the magnum primer, as mentioned in a medium case you will more then likely see pressure signs sooner as more powder will burn at once..
if you really feel that the primer is holding you back swap to a harder primer like CCI (you didnt mention what you use now) the harder cup will handle a bit more pressure then something like a federal that tend to be on the softer side
if you really feel that the primer is holding you back swap to a harder primer like CCI (you didnt mention what you use now) the harder cup will handle a bit more pressure then something like a federal that tend to be on the softer side
- Location
- lloydminster
Whats happening is your burning all your powder pretty much at once with the magnum. So you have a quick flash and high pressure rather than the powder burning near its intended burn rate which produces the gases need to continue to push the bullet faster down the barrel.
Chinbullco
Regular
- Location
- NW Alberta
Try Lapua 308 Palma brass resized. Used these for a 7-08 Improved load and use them in my F-T rifles. Using powder charges that were expanding regular 308 Lapua primer pockets, the Palma brass is on its 8th reload. Start low and approach max loads cautiously. Using CCI-450 small rifle primers.
