magnum primers

[mikeyg]

if I use small rifle magnum primers instead of regular small rifle primers what changes,if any, do I need to make in my loads?

[Toddco]

i have changed the primers in large rifle and found that when i go to magnum there is an increase in pressure, so i assume it would be the same in small. I would suggest you reduce your load and work back up in small increments.

[mikeyg]

thanx.any ideas on how much reduction? I'm loading for a 204 ruger. also what do I look for to determine unsafe pressure?

[jimbob86]

..... but my advice would be : Don't.

If the published load data calls for magnum primers, use them. If not, don't.

Magnum primers will steepen the pressure curve, and folks with the spendy test equipment get paid to develop those loads.

You might not run into trouble playing hopscotch at the City Limits of Splodeyville ...... or you might damage your rifle or poke holes in yourself.

I am thinking that a steeper pressure curve would make those "city limits" a lot less defined- less difference between a charge that develops insufficient pressure to be efficient and consistent, and one that exceeds pressure limits of the case or rifle (I imagine the latter = Very Bad Ju-Ju).

Find a published load that calls for the magnum primers, or save them for another gun/load later on in life- it's not like they will spoil on you, so long as you keep them in a cool, dry place.

...just my $.02 worth, and that's more than you paid for it.....

[GP100man]

when I approch hi pressure in rifles (bolt) the bolt will be harder to lift.

The next thing I do is measure the case head, & compare it to an unfired case .

[mikeyg]

thank you all. anyone know the best powder to start off with for the 204? I've heard H335 or 332,Benchmark are good choices. what about IMR 3031?

[Uncle Buck]

I am using 3031 in my 30-30 reloads and both my nephew and I like it.

I usually try several powders for each round I reload before I settle on one I like. I tried the 3031 first and was very happy with the result and did not even try another powder.

[steve4102]

Go ahead and use the Mag primers. Just do as you would always do and start your load development at the "Start" charge and work up.

BTW, what brand of SR primers both Mag and regular are we talking about.

[Bamashooter]

my rifle hasnt blown up and ive reloaded and shot 100's of .223 ammo with magnum primers. some of my best groups have been with magnum primers. i never load to max capacity so i didnt back off any with the mag. primers. if i was to load to max capacity i would back off some. i checked all the cases after i fired them and there was no signs of high pressure.

[Toddco]

The best powder i have found for my .204 is the new imr 8208 xbr. To emphasize what the others are saying about mag primers in your .204, if you have a choice stick with the smalls, the .204 already runs a high pressure curve. When i loaded 39 grain sierra's with the xbr powder i have chronographed speeds of 3800 fps, do you really need any more boost?

[oneoldsap]

When ever you change any component of an established load , reduce your charge by 10% or just start over . The results may be quite different with the mag. primer , might not group at all .