Magnum or standard primers.

[thwatson2]

I use federal magnum primers in all my rifles. From 220 swift to 375 H&H and everything in between. It streamlines my shelf and I don't worry I switched up something. No second guessing! My loads are developed from there using a chrono. If I do run out and can't find them in stock I use Winchester magnum primers. Although ive had quite a few duds in Winchester, hence reason I primarily use federal

 

[blackbrush1]

Rules? There are no rules in this regard (don't use a pistol in a rifle). Test for accuracy and SD. If close, I use magnums especially for cold weather applications

 

[30BR]

For 600 yard BR, a LOT of guys use the CCI 450 magnum SR primer even with Reloder 15 in the little BR case for 6mmBRDX and Dashers... As others have said, don't worry about "will it work?"; try it by dropping the powder charge to minimum levels and work your way up.

 

[rbTanzan]

The bullet type is also a factor.
Some bullets like GSCustom and Hammer Hunters have very low engraving pressure.
I usually find more consistency with magnum primers in those cases, even in little calibers like 243W.
For example, 47.4 grains H4350, 70gn HH, Rem9.5mag. But I've got a nice 243 load with Barnes 80gn TTSX, 45.5 R16, and regular cci-br primers.

 

[ranger3]

My 223 and 6BR both use city 450 primers for most loads
My 22 250 uses 9.1/2 mag primers for ball powder loads . All other large primer loads use 210M primers.

 

[Quintus]

When I first started loading I ran all Federal 215s. 243 to 300Bee. I later revisited several loads in various cartridges based on the 308 and 30-06 cases and found noticeable accuracy gains and load flexibility by switching to Large Rifle Standard primers. I do still have a .260 load worked up with Fed. 215M primers that I run when it is 5 degrees or colder, but that is the only case under 65 grain Cap I use mags in any more.

 

[J E Custom]

Not sure if this has been asked before. What is the point at which some one should switch from standard to magnum primers. Does it go by charge weight,burn rate of the powder or temp most shooting will be done. Part of the reason I am asking is I am working up a load for my 280 Rem. I am using slow powders in the burn rate of Rl 25 to push the 168 VLD Hunting bullet. These powders max around 60 grains of powder give or take. I started load work up with the Fed 210M primers but I am wondering if the 215 might be a better choice. Seeking the help of the experts here.

If you have a chronograph, let the load tell you what you need. The magnum primers will normally add velocity to the load but in the case of smaller cartridges they can also increase the SD's. with many mid size cartridges 60 to 80 grain of powder the standard large rifle will produce better Standard Deviations and slightly slower velocities. I have always chosen accuracy over velocity. So I look at SD's to get the most/best consistency which normally produces the best accuracy.

The larger cartridges that burn lots of slow burning powder almost always need the magnum primers But sometimes it is worth trying if you are not in extremely cold climates to improve accuracy.

The 7 STW's come to mind because they seem to like both magnum and standard primers depending on the powder and bullet combination. With the small cartridges, magnum primers can actually change the way faster burning powders react and increase the SD's to the point of inconsistency.

Good SD's indicate a good primer, powder and bullet combination and is always the place I start to develop accurate loads. After good SD's are found, for accuracy, I look at different bullet shapes and seating depths for best accuracy, by changing one thing at a time.

Start with standard primers and then If SD's aren't good try magnum primers. But always start with the recommended primer in the load data.

J E CUSTOM

 

[nmbarta]

I run 210m's in my 280ai, 59.5 H4831sc
The accuracy and SD's were quite a bit better than with the 215m.
I've shot it quite a bit in very cold temps (-10) with no problems.
Keep in mind we use 215m's to light 130+ gr of powder without problems. Standard primers don't have any trouble lighting up to 70 gr in my experience.
It's amazing what changing primers can do for accuracy

 

[Mike Matteson]

I use large rifle Fed 210, and stay with that primer. It's now my understanding they are the hottest large rifle primes on the market. I am generally loading in the middle 70 grains of powder and using 26" barrels. Most of my powder is H4350SC. If I am going to use a Mag primer, I would reduce my powder load by at lease 5% to start with. I am generally several grains over what the reloading book calls out for. If the reloading books calls out Mag primes, I start with their reduced load and work up from there. My thinking is I am trying to burning the powder to the end of barrel to gain the velocity, not in the first few inches of the barrel, to cut down the pressure at the start. There by reducing the overall pressures somewhat. I maybe wrong, but that how I figure it. Where powder loading is beyond that pushing 75+ grains and up. I would says Mag primes would come into use. Some mag rifle are burning 90+ grains of powders. Some are using shorter barrels and there a need to get the powder burn before the end of the barrel to achieve a full powder burn and velocity. You need a chronograph to tell you where you're at. Otherwise just wasting powder and bullet for little gain.

 

[Dean2]

We hunt in weather for +80 to -45. ALL of our hunting loads are developed from the start using Magnum rifle primers, CCI 250 from 40 to 70 grains, and Winchester mag or Fed 215 above that. Anyhing that uses 90 grains or more gets Fed 215 for sure. We work on powder, primer bullet to get low SDs, without having to go to standard LR primers. We have seen click booms or failure to ignite, with burned clumped powder in the unfired case, on 7 RUM, 378 Bee, 460 Bee etc using more than one batch of CCI 250 primers. They are not hot enough for the big powder loads shooting slow burning powder, even at +40F. For many shooters this may not be a consideration, especially the temperature extremes, but up here, reliability is key and I would actually trade to a 1/4" bigger group to ensure it goes boom reliably.

 

[gvjm]

I just go by the "book". I run a 300 Hamr. It recommends mag primers for all their loads. Max loads are around 27 grains.

 

[Mc Fraser]

Assuming the same conditions, everything the same, switching to magnum primers, should one be aware of increase pressure? Any safety concerns?

 

[asd9055]

Assuming the same conditions, everything the same, switching to magnum primers, should one be aware of increase pressure? Any safety concerns?

Yes. Always back powder down and work back up

 

[Dean2]

Assuming the same conditions, everything the same, switching to magnum primers, should one be aware of increase pressure? Any safety concerns?

Unless you are shooting loads that are at or close to book max I will differ from the norm and say no. To be completely safe you should back off to the mid point and work back up but in all the times I have switched from one primer to another I have never seen it make any noticeable difference in pressure., certainly not enough to go from safe to popping primers, enlarging primer pockets let alone lock up a bolt. I have seen far bigger differences from switching lots of powder than I have ever seen switching primers. That said, I never hunt with loads that aren't at least a full grain below max published velocity. Would nver want to lock up a gun due to heat or other nonsense shooting ragged edge hot loads.