I'm down to my last 100 Federal 210 large rifle primers, and I have idea where I'll get more when these are gone. What I do have is 500 Federal 215M magnum primers. I have heard a lot of theories, some sounding technical and others, not so much, about using the magnum primers in place of the large rifle. Nowhere have I run across what I consider serious, reliable information on how much centerfire rifle powder loads should be reduced when magnum primers are substituted for large rifle. Maybe I'm the only one that doesn't know the answer to this? Maybe the magnums don't really make a much difference or maybe they are not recommended at all?
Load reduction using magnum primers
- Thread starter Crumster
- Start date
RegionRat
Gold $$ Contributor
You will only get generic or anecdotal advice when you don't name the specific cartridge and your specific recipe.
You can find examples of loads where a primer swap from 210 to 215 makes little or no difference, and others where it does.
In the absence of more specific information... My advice is if your pressure is already on the high end, play it safe and start a grain lower and work back up. In terms of pressure, that would be to say drop it about 4 to 7 KSI and then work back up. If you want better advice, give the details.
You can find examples of loads where a primer swap from 210 to 215 makes little or no difference, and others where it does.
In the absence of more specific information... My advice is if your pressure is already on the high end, play it safe and start a grain lower and work back up. In terms of pressure, that would be to say drop it about 4 to 7 KSI and then work back up. If you want better advice, give the details.
Always good practice to rework the load when swapping primers.
searcher
Gold $$ Contributor
I have wondered about the difference of magnum and regular primers in respect to velocity too. Several years ago, I did a test (SMALL rifle primers) whereby I tried a number of different primers with my favorite varmint load for a .223. I used Remington 7 1/2, Federal A/R Match, CCI450, Tula .223 primers, Tula .223 Magnum primers, Wolff, Federal small rifle primers and maybe another. I only shot 10 rounds of each over a Magnetospeed chrono using same bullets, brass and charge. The extreme spread from lowest velocity to the highest velocity was only something like 40-45 FPS and in two cases, the magnum primers came in with less velocity than the non-magnum primers. While certainly not a test to draw absolute numbers from any of them - it did show me that I could do a simple (and small) powder adjustment when swapping out primers - whether magnum or not. I alternated in 5-shot strings so I could average two groups of five to see if any of the primers had adverse accuracy with the load. While some groups were maybe 1/8"+/- larger than others - I couldn't attribute that to the primer with such a small sampling - but it did show me none produced anything bad. If I were not running a hot load, I'd feel comfortable swapping them out with no fear. If near the top of a load, I'd back off 1/2 grain and feel comfortable. There are online charts that show a lot on the differences between the primers in respect to thickness, flash intensity, etc. Some of the magnum primers are better at igniting certain kinds of powder than others and you can get better ES's. I'd give them a try.
In 30.06 and 300WM with N550 and N560 I changed from Fed 215s to Fed 210s and I had to adjust both loads upwards between 2 and 3gr to get to the same speed again.
I played around with 215s and CCI BR2 in 243 and 6.5x55 using very slow powders and there were also around 1.5gr difference "in speed" between the 2 primer in those cases, then on the other hand I changed out CCI BR2 primers for Muron Magnum primers in an Improved 243 case without seeing much difference.
I think the powder you use plays a big roll in the "difference" between a magnum and non magnum primer and obviously your case size as well, the Fed 215s are known to be hotter then most magnum primers.
Just load 5 rounds with a 1.5 or 2gr reduced load to be safe and check your velocities over a crony and go from there
I played around with 215s and CCI BR2 in 243 and 6.5x55 using very slow powders and there were also around 1.5gr difference "in speed" between the 2 primer in those cases, then on the other hand I changed out CCI BR2 primers for Muron Magnum primers in an Improved 243 case without seeing much difference.
I think the powder you use plays a big roll in the "difference" between a magnum and non magnum primer and obviously your case size as well, the Fed 215s are known to be hotter then most magnum primers.
Just load 5 rounds with a 1.5 or 2gr reduced load to be safe and check your velocities over a crony and go from there
Not sure about large rifle primers but with small rifle primers the word magnum can mean two different things. The first and what most think of is it is a hotter primer for ball powder(harder to ignite) and for "slower" stick powder also harder to ignite and for extreme cold weather. And this is true of some SRP's. It can also be used to denote a thicker "cup" for higher pressure loads.
For safety sake, drop the load a grain or two and work back up.
Frank
For safety sake, drop the load a grain or two and work back up.
Frank
Run an abbreviated powder ladder side by side using the two primers , you may not see a hell of a lot of difference in point of impact but the node might move slightly. Either way you’ll have your answers.
A test of 15 LR primers that I did in 308 Win around 10 years ago.
https://www.targetshooter.co.uk/?p=1471
In the 308 and similar size cartridges, I'd drop the powder charge 1gn and retune from there going from the F210 to F215M, but as others have said, much depends on the cartridge, and even the powder used.
https://www.targetshooter.co.uk/?p=1471
In the 308 and similar size cartridges, I'd drop the powder charge 1gn and retune from there going from the F210 to F215M, but as others have said, much depends on the cartridge, and even the powder used.
The cartridge that I'm working with at the moment is a 22-250 Remington. From reading the responses here; I think my question has been answered. There is no standard when it comes to this situation. It seems a little strange that some mathematician hasn't taken a few minutes out of his less than busy life to come up with an equation that, with certain givens, couldn't be useful.
Crumster, Here is the formula for you seek:
a=b/c(d+e-f)+2.34567890*-1.111+~g*h*j-k+(l-m+n)/p (round number to the 37th decimal place)
Yes there are a LOT of variables!
Frank
a=b/c(d+e-f)+2.34567890*-1.111+~g*h*j-k+(l-m+n)/p (round number to the 37th decimal place)
Yes there are a LOT of variables!
Frank
Thanks Frank.
Attachments
With .223, I've seen a pick up of 40 FPS going from Wolf SRM to Fed AR Match. And over 60 FPS on some loads going from Wolf SRM to CCI 450/41s. Probably has a lot to do with the powder too.
WooHoo be fun to know the chamber pressures!
WLR available now. Scroll to the bottom for WLR 1000 count
I have made up my mind to switch to my magnum primers when the lg rifles' run out, but I thought I'll go ahead and get 100 of the Winchesters. That went out the window when I noticed that the shipping is nearly 300% more than the price of the primers!
If you live near a Cabelas or a Bass Pro you could get it sent there with no charge and pick it up... but you probably don't have one nearby. I just thought I would send it to you while they had them in stock. I hear LR and LP are hard to find out there.
Texas Solo
B.S. High Master
Using IMR4064 in 308, I was at a medium charge weight so I didn't worry about. Went from WLR to WLRM. I picked up 50fps with no change in group size or POI.
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