An Investigation of Primers
I have for many years been a devotee of Federal Rifle Primers, both 215 for the larger capacity cartridges, and 210 for standard cartridges. I use a lot of Federal 215 and 210 primers. During some recent primer shortages I was unable for months on end to get extra shipments of these primers, and was offered several times for my order to be replaced with both CCI and Winchester, of which I refused and waited for the Federals, which did finally come before I ran totally out.
This did prompt me to consider other primers however, but the question remained how that would affect performance of loads that I had established already with either Federal 215s or 210s? I decided to conduct a study of this to find out.
Having worked with the Pressure Trace System for several years I decided to use that in combination with the chronograph to gather as much data as possible to go beyond just a velocity study, and see how pressures were affected as well. Knowing how the slightest change in any component can make a huge difference in pressures, and sometimes no difference at all in velocity, the pressure trace is considered to be an important component of the study. And in the end it has proven itself once again. Several of the tests provided near same velocity, but vastly different pressures.
I decided one could not just test one powder, one bullet, and one cartridge, and realize any value in that. So I decided to do at least 3 different B&M cartridges, 2 different bullets each, along with two different powders, and see if one was able to gather enough data to realize if one primer stood out above others, or one might stand out as not so good? To begin with I chose the 9.3 B&M, 416 B&M, and the 50 B&M as the test cartridges. Two bottle necks, one medium bore, and then the 50 B&M as the basic straight case. Each of these at their best with totally different powders.
Sam Rose and I did the first test back in February of this year, 2011. We did the 416 B&M at that time. It was only recently I was able to resume the test work with the 9.3 B&M. My 50 B&M with the strain gages connected is out for a new stock right now, and since I was not able to work with it I decided to conduct a test in the 458 B&M, and when the 50 B&M is returned I will then finish the test with it.
9.3 B&M Primer Test
In the 9.3 B&M I decided to use the CEB 255 BBW#13 HP and it's favorite dose of 69 grs of RL 15. This is an excellent load and was worked up with the Federal 215 to begin with. The following primers were tested, Federal 210, Winchester Magnum, Winchester Standard, CCI-250, Wolf, and MagTech. Many of these being supplied by Sam Rose. The same primers were used with the 286 Hornady and 66/IMR 4320. A better load for the 286 Hornady is again RL 15, however I wanted to use a different powder, and this load is at Maximum, a slight push or change in primer could push it over maximum.
With the 255 CEB BBBW#13 and 69/RL 15 the Federal 215 did a great job. Took the load to some less than maximum and gave extremely consistent and even pressures, and the highest velocity. The Winchester Magnum primer gave a slightly lower pressure, but with a very high extreme spread, not showing good consistency, but velocities were consistent.
With the 286 Hornady and 66/IMR 4320 the Federal 215 gave some inconsistent pressures, with excessive extreme spread, very consistent velocity numbers. With this load, the CCI 250 gave near the same velocity, very consistent pressures and much lower pressure.
Conclusion? Obviously more work would need to be done to confirm this, but it appears one could in fact fine tune the pressures and loads by checking several different primers. For instance in this case with the 9.3 B&M, I would not investigate much further the 255 CEB BBW#13 Load with the Federal 215. However, with the 286 Hornady and IMR 4320 I could investigate the CCI 250 primer further, lower the pressures a good bit below maximum and nearly equal the velocity.
Please find the 9.3 B&M Data Below in PDF format.
416 B&M Primer Test
Here again, 2 different bullets, two different powders were chosen for the 416 B&M. Sam Rose assisted in this test and we used the 330 SSK/Lehigh Brass NonCon with AA 2520, and the 400 CEB BBW#13 Solid with WW748. Both top end powders for the 416 B&M with various loads.
With the 330 SSK/Lehigh we used 74/AA 2520. Top load for the 416 B&M lower than maximum pressures, all original data worked up with the Federal 215 as always. And in this case the Federal 215 looked very good and very acceptable in the test. In fact, all primers tested with this load looked great. With some really showing us something new. In fact the Federal 210 gave within 30 fps of the Federal 215, but at 5000 PSI less pressure, and very good extreme spread of both pressure and velocity.
The 400 CEB BBW#13 with 75/WW 748 gave some very excessive extreme spreads with the pressures, and at times the extreme spread was showing on the chronographed velocity as well. Average velocity of all primers was close to the same, however the MagTech primer really came out nice in this test with very low extreme spreads of velocity and pressures. The Winchester Standard primer gave excessive extremes, I would not be happy with that load myself.
Conclusions? Again, one could do some fine tuninig with primers, no doubt, but you would in most cases have to be running a pressure trace, or similar system to realize it. In some cases, yes, velocity can tell you, but most of the time a chronograph alone will not.
Find the 416 B&M Primer tests below in pdf format.
458 B&M Primer Test
I probably made a mistake with the 458 B&M test work. I noticed I needed new 458 B&M brass, so I used "formed brass" just from the size die, not already fire formed. Formed brass gives vastly different pressures than what fire formed brass does. In some cases, it adds pressure over fire formed brass, in others it gives much lower pressures. Sometimes it also gives inconsistent pressures as well. Desperate for brass, I used formed brass anyway! Honestly, I could not verify that the tests with the 458 B&M are valid or not. I am going to post it here anyway, and decide later whether it warrants a re-test or not.
Using the cheap 405 Remington I chose IMR 4198 and just under maximum load for a 400 gr bullet. On the upper end, I used a 450 BBW#13 NonCon with what showed to be a load with fire formed brass that topped at or around 58000 PSI. In this formed brass it was only giving from 37000 to 49000 PSI, but velocity was the same as for the fire formed brass! Amazing actually. Something in and of itself that calls for further investigation I think!
I used 65/IMR 4198 with the 405 Remington, velocities with all primers were very close, and excessive extreme spreads with most primers with the exception of the Federal 210 that really gave some close pressure numbers, but the most extreme spread on velocity? Backwards from what one would think. If I were looking at this from a standpoint of getting the most velocity, least pressures, then this is the test. CCI 250 gave us 2296 fps and 51000 PSI, the standard load with the Federal 215 gave 2309 fps but at 61800 PSI! That is a huge difference. I would test one more or two more grains of IMR 4198 and the CCI 250 to check those results! Other primers gave low pressures as well, Wolf being the lowest average, but highest extreme spread, Federal 210 and Winchester Standard making a good show as well.
Numbers were much closer with the 450 BBW#13 NonCon and 65/H-322. This is one load that all primers were consistent across the board and gave excellent extreme spreads and the same with velocities. What is extremely strange is that the pressures using the formed brass are so much lower than normal fire formed brass, while velocity stayed the same. In other cases the pressures go up using formed brass.
Please find the Data Below.
What have the tests told us so far? With some loads, depending on the powder, bullet, and case, one can improve the load by trying different primers. One can get close to top end velocity, at lower pressures, which is a major step in the right direction. You must have the right equipment to get this technical however, a simple chronograph will not always get you there. One of the reasons I always use Federal Primers is the consistency, along with the reliability. I have used many 1000s of primers over the years, and only once had a Federal not fire and receive a good primer blow. I trust the Federal primers to be as good as a primer can be. With this said, I have little experience with other primers in big bore rifles, more here in this test work than all combined in years past.
I will be doing more and adding to this work in the future. I still have one major test to go through with a straight case, the 50 B&M, to see how primers react in that sort of case. When that is completed, I will add that. I may also try some other powders, and bullets, within the cartridges we have already tested. I also think that I might investigate some of these top end high pressure loads, try some different primers to see if I can reduce pressures, but maintain velocities, or close. In doing so, again I will report back here with that information.