I have been reading and if I am not mistaken we can sub any like primer in the recipe's? Small pistol to small pistol of any brand, magnum large pistol to magnum large pistol ect. Didn’t know if brands had an impact, specifically in the H110 loads for 44 and 357 mag. I prefer to use CCI as I already have stock of them.
Primer brand interchangeability
- Thread starter Clubster
- Start date
The standing advice for generations has been and still is the same. When you change any component, you drop back to your starting load (or below) and work your way up again with the new component.
The logic here is that while all primers, cases, and bullets (and sometimes even lot#s of powder) ought to be the same, they often are not exactly the same, and you and I don't know what the difference might be, or what results it will produce.
Things ought to be safe but we don't know that they will be safe until tested and proven.
People do it all the time, and generally get away without any dangerous results, but they shouldn't. BUT.., sometimes what you think will be
results in 
, and then often 
Dropping back to start and working up again costs some time, and uses some components, but it does prove if things are going to be ok, or not.
Switching primers from Brand A to Brand X (and doing nothing else) might result in no significant change, or it might change the accuracy of your load, or give erratic ignition, or even bump the pressure up to the point your brass shows it. Though some things are not likely, ANYTHING IS POSSIBLE, and this includes bad things, until testing shows what things actually are, and that they are safe, or not...
The logic here is that while all primers, cases, and bullets (and sometimes even lot#s of powder) ought to be the same, they often are not exactly the same, and you and I don't know what the difference might be, or what results it will produce.
Things ought to be safe but we don't know that they will be safe until tested and proven.
People do it all the time, and generally get away without any dangerous results, but they shouldn't. BUT.., sometimes what you think will be
results in , and then often Dropping back to start and working up again costs some time, and uses some components, but it does prove if things are going to be ok, or not.Switching primers from Brand A to Brand X (and doing nothing else) might result in no significant change, or it might change the accuracy of your load, or give erratic ignition, or even bump the pressure up to the point your brass shows it. Though some things are not likely, ANYTHING IS POSSIBLE, and this includes bad things, until testing shows what things actually are, and that they are safe, or not...
H110 generally prefers magnum primers.
As 44amp stated, not all primers are the same. No you do not have to use what is listed in the book, but whichever primer you choose you should do a load workup with that primer to verify its safe and or functioning normally.
CAUTION: The following post (or a page linked to) includes or discusses loading data not covered by currently published sources of tested data for this cartridge (QuickLOAD or Gordon's Reloading Tool data is not professionally tested). USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assumes any liability for any damage or injury resulting from the use of this information.
Personally for 357mag I switched over to regular small rifle primers as they were cheaper and easier to find and something I already used. in 44mag you do have to use pistol primers, large rifle primers are deeper and generally will not fit and cannot/should not be used.
My personal preference has always been CCI. I try to avoid Federal primers as they way they are packaged is bulky and makes them hard to use. Fiocchi primers come in weird sized trays but all seemed to work well. Winchester primers are ok, but i generally find I do not get the best es/sd with them
As 44amp stated, not all primers are the same. No you do not have to use what is listed in the book, but whichever primer you choose you should do a load workup with that primer to verify its safe and or functioning normally.
CAUTION: The following post (or a page linked to) includes or discusses loading data not covered by currently published sources of tested data for this cartridge (QuickLOAD or Gordon's Reloading Tool data is not professionally tested). USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assumes any liability for any damage or injury resulting from the use of this information.
Personally for 357mag I switched over to regular small rifle primers as they were cheaper and easier to find and something I already used. in 44mag you do have to use pistol primers, large rifle primers are deeper and generally will not fit and cannot/should not be used.
My personal preference has always been CCI. I try to avoid Federal primers as they way they are packaged is bulky and makes them hard to use. Fiocchi primers come in weird sized trays but all seemed to work well. Winchester primers are ok, but i generally find I do not get the best es/sd with them
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Jim Watson
New member
I compared eight small primers in 9mm; pistol, magnum pistol, rifle.
All but one gave the same velocity within 8 fps, a coated 135 and 3.8 gr HP38, 1018 to 1026 fps. Remington 1 1/2 small pistol was clear up at 1042 fps.
Now that was one load in one gun several years ago, so substitute with caution.
I have since gone to 124 gr bullets, but find the White River Energetics primer 16 fps faster than Federal, Fiocchi 64 fps slower! I should probably rerun that one, it only took 0.2 grains more powder to get Fiocchi up to Minor power factor.
All but one gave the same velocity within 8 fps, a coated 135 and 3.8 gr HP38, 1018 to 1026 fps. Remington 1 1/2 small pistol was clear up at 1042 fps.
Now that was one load in one gun several years ago, so substitute with caution.
I have since gone to 124 gr bullets, but find the White River Energetics primer 16 fps faster than Federal, Fiocchi 64 fps slower! I should probably rerun that one, it only took 0.2 grains more powder to get Fiocchi up to Minor power factor.
My only experience is with rifle rounds. Not making any claims that they are BEST, but when I started Winchester Large Rifle is what I could find and for the most part that is what I've stayed with. Always got me the accuracy and speed I was looking for so I never looked elsewhere unless I couldn't get them.
I did load a few rounds with CCI large rifle once when I ran out of Winchester and briefly couldn't find any. After some experimenting with lighter powder charges I eventually moved back to the same powder charge I'd used before. In this case it didn't make any difference.
I also had a 7RM and 300 WSM at one time and used CCI Large Rifle Magnum primers for them. I didn't keep the 7mm mag long and when I was no longer able to find magnum primers started using the standard Winchester Large Rifle magnums in the 300 WSM. Absolutely no difference in speed or accuracy.
I would absolutely advise dropping down some if you change. It may or may not make any difference, but you never know until you try.
I did load a few rounds with CCI large rifle once when I ran out of Winchester and briefly couldn't find any. After some experimenting with lighter powder charges I eventually moved back to the same powder charge I'd used before. In this case it didn't make any difference.
I also had a 7RM and 300 WSM at one time and used CCI Large Rifle Magnum primers for them. I didn't keep the 7mm mag long and when I was no longer able to find magnum primers started using the standard Winchester Large Rifle magnums in the 300 WSM. Absolutely no difference in speed or accuracy.
I would absolutely advise dropping down some if you change. It may or may not make any difference, but you never know until you try.
Different brands of primers can have a slight impact on accuracy and a slight impact on performance ... the big word being "slight " impact .
CCI primers are the reloaders "Gold Standard" ... usually what I use when available .
If the Load data calls for Winchester Large Rifle and you use CCI large Rifle ... you will see no dangerous differences .
Different brands may show a slight difference in velocity but every firearm will show slight differences ... and not because of different primers .
I use CCI when I can and any American made primer when I can't get CCI ...
Like Winchester , Federal , Remington , Magtech ... even some old Alcan primers ...
They is all Good !
Gary
Usually safe as long as you stay within published load data. There are primer & powder combinations called out sometimes that should be adhered to for best results, e.g. H110/W296 44mag loads in very cold weather - almost always calls for a magnum primer. (I have had squibs in the winter).
Over the years I've chronographed a lot of primers in 9mm, 40sw, 45acp, 44mag and found they have little impact on velocity, hence pressure.
Accuracy is affected by primer choice and top shooters know their primers well.
I've included a link to an article comparing small rifle primers that you might find interesting.
https://www.targetshooter.co.uk/?p=2662
It depends. There is a good pair of plots on page 130 of the print version of the 2013 Norma Reloading Manual comparing primer brands in a 300WM firing a 180-grain bullet with 5.3 grams (81.8 grains) of their MRP powder in a Norma case. The variation at 22°C (71.6°F) and up was small, yielding about 8 m/s (26.25 ft/s) difference in velocity and about 45 mPa (6,527 psi) difference in peak pressure. However, when it came to winter weather and lower temperatures, the performance dropped off at somewhat different rates, and the Federal 215 Magnum Large Rifle Primer held up pressure and velocity significantly better than other brands did in the cold. At -10³C (14°F), the 215 produced 21 m/s (69 fps) more velocity than the CCI 250, and at -40°C (-40°F, the temperature at which the C and F scales cross), that difference rose to 41 m/s (134.5 fps), at which point the peak pressure difference was 70 mPa (10,153 psi). Incidentally, throughout the test, from 10°C (50°F) and higher, the Federal 210, LRP, produced the highest velocity and was only outperformed by the Federal 215 below that temperature and was halfway between the F215 and CCI250 at the very cold temperatures.
In other words, if you compared all the LRM AND the LR primers in the summer, you'd see little difference, but if you compared them in sub-zero weather, you'd see a more significant difference.
In other words, if you compared all the LRM AND the LR primers in the summer, you'd see little difference, but if you compared them in sub-zero weather, you'd see a more significant difference.
I just analyzed my results with a 12 FV .223 rifle over a large number of groups.
Using a simple comparison of all 5-round groups shot with two different benchrest primers (CCI BR-4s and Remington 7 1/2s), the results would favor the Remington primers by a lot.
Overall measurements over 1,308 5-round groups show that BR-4s average 0.291 and the 7 1/2s average 0.276, so there would seem to be a clear winner.
But simple comparisons often misrepresent the truth.
But, over the years, I changed the original factory stock to an Oryx Chassis and the original Sightron II 36X scope to a Leupold Competition 45X scope, and the Oryx and Leupold 45X produced the best results.
Considering the results using just the Oryx Chassis and the Leupold 45X scope:
214 BR-4 groups averaged 0.275 and
916 7 1/2 groups averaged 0.274.
The numbers of groups shot are large enough to be statistically significant by anyone's standards so the results are pretty conclusive.
The conclusion is that the 0.001 difference in 5 round groups size is statistically insignificant so the results could be considered equivalent.
Considering my shooting results show a pretty consistent 0.050 standard deviation among all the groups shot, I would say that my shooter induced variation was far greater than the variation due to the primers.
Some of our very best shooters might be able to shoot with much smaller shooter induced variations that I create and might be able to see the small contribution in primers might make, but the totals indicate that, if the variable conditions of equipment are eliminated, the differences should remain pretty small, at least, among small rifle benchrest primers.
Using a simple comparison of all 5-round groups shot with two different benchrest primers (CCI BR-4s and Remington 7 1/2s), the results would favor the Remington primers by a lot.
Overall measurements over 1,308 5-round groups show that BR-4s average 0.291 and the 7 1/2s average 0.276, so there would seem to be a clear winner.
But simple comparisons often misrepresent the truth.
But, over the years, I changed the original factory stock to an Oryx Chassis and the original Sightron II 36X scope to a Leupold Competition 45X scope, and the Oryx and Leupold 45X produced the best results.
Considering the results using just the Oryx Chassis and the Leupold 45X scope:
214 BR-4 groups averaged 0.275 and
916 7 1/2 groups averaged 0.274.
The numbers of groups shot are large enough to be statistically significant by anyone's standards so the results are pretty conclusive.
The conclusion is that the 0.001 difference in 5 round groups size is statistically insignificant so the results could be considered equivalent.
Considering my shooting results show a pretty consistent 0.050 standard deviation among all the groups shot, I would say that my shooter induced variation was far greater than the variation due to the primers.
Some of our very best shooters might be able to shoot with much smaller shooter induced variations that I create and might be able to see the small contribution in primers might make, but the totals indicate that, if the variable conditions of equipment are eliminated, the differences should remain pretty small, at least, among small rifle benchrest primers.
Name of One Who Uses
New member
I personally don't worry much about switching primers so long as my loads aren't near max, which mine rarely are any more. If I were loading near max and wanted to switch primers, I would probably back off and work my way back up.
For a few years I loaded/fired a lot of .30 Carbine. I did, and still do, use whatever primer was handy that fit the primer pocket; SPP, SPMP, SRP and SRMP. My curiosity got the best of me so I decided to chronograph some loads with all components being identical except the primers. Here's how that went-
Components-
Case- LC 71
Powder- 14.8 gr. Ramshot Enforcer (AA4100)
Bullet- Armscor 110 gr. FMJ
Cartridge o.a.l.- 1.660"
Fiocchi SPP- 1952 fps, 11 fps ES
CCI500 SPP- 1964 fps, 20 fps ES
CCI550 SPMP - 1993 fps, 12 fps ES
Rem 6 1/2 SRP- 1992 fps,18 fps ES
CCI400 SRP- 1984 fps, 56 fps ES
CCI450 SRMP- 1978 fps, 53 fps ES
Wolf SRMP- 1971 fps, 58 fps ES
As one can see, there's no appreciable difference in velocity between the primers. I think this would tell us that the pressure differences are also very small with no particular primer standing out as adding to or reducing pressure. (As a side note, the Fiocchi SP has been my go-to for .38 Special practice loads and it yielded lower velocities than other primers in that cartridge too)
If you're a math nerd, the average velocity of all the different primers was 1976 fps and the extreme spread between the slowest and fastest was only 41 fps. Going from memory, the extreme spread between the lowest and highest individual rounds was about 65 fps.
Components-
Case- LC 72
Powder- 15.0 gr. of W296 (H110)
Bullet- Armscor 110 gr. FMJ
Cartridge o.a.l.- 1.660"
Fiocchi SPP- 1934 fps, 69 fps ES
CCI500 SPP- 1960 fps, 69 fps ES
CCI550 SPMP - 1973 fps, 62 fps ES
Rem 6 1/2 SRP- 1976 fps, 39 fps ES
CCI400 SRP- 1993 fps, 23 fps ES
CCI450 SRMP- 1967 fps, 41 fps ES
Wolf SRMP- 2004 fps, 54 fps ES
For you math nerds the average velocity of all the primers with W296 powder was 1972 fps with and extreme spread of 70 fps.
FWIW I find the .30 Carbine and .357 Magnum, despite their difference in bore sizes, behave very similarly and are even at their best with similar powders.
For a few years I loaded/fired a lot of .30 Carbine. I did, and still do, use whatever primer was handy that fit the primer pocket; SPP, SPMP, SRP and SRMP. My curiosity got the best of me so I decided to chronograph some loads with all components being identical except the primers. Here's how that went-
Components-
Case- LC 71
Powder- 14.8 gr. Ramshot Enforcer (AA4100)
Bullet- Armscor 110 gr. FMJ
Cartridge o.a.l.- 1.660"
Fiocchi SPP- 1952 fps, 11 fps ES
CCI500 SPP- 1964 fps, 20 fps ES
CCI550 SPMP - 1993 fps, 12 fps ES
Rem 6 1/2 SRP- 1992 fps,18 fps ES
CCI400 SRP- 1984 fps, 56 fps ES
CCI450 SRMP- 1978 fps, 53 fps ES
Wolf SRMP- 1971 fps, 58 fps ES
As one can see, there's no appreciable difference in velocity between the primers. I think this would tell us that the pressure differences are also very small with no particular primer standing out as adding to or reducing pressure. (As a side note, the Fiocchi SP has been my go-to for .38 Special practice loads and it yielded lower velocities than other primers in that cartridge too)
If you're a math nerd, the average velocity of all the different primers was 1976 fps and the extreme spread between the slowest and fastest was only 41 fps. Going from memory, the extreme spread between the lowest and highest individual rounds was about 65 fps.
Components-
Case- LC 72
Powder- 15.0 gr. of W296 (H110)
Bullet- Armscor 110 gr. FMJ
Cartridge o.a.l.- 1.660"
Fiocchi SPP- 1934 fps, 69 fps ES
CCI500 SPP- 1960 fps, 69 fps ES
CCI550 SPMP - 1973 fps, 62 fps ES
Rem 6 1/2 SRP- 1976 fps, 39 fps ES
CCI400 SRP- 1993 fps, 23 fps ES
CCI450 SRMP- 1967 fps, 41 fps ES
Wolf SRMP- 2004 fps, 54 fps ES
For you math nerds the average velocity of all the primers with W296 powder was 1972 fps with and extreme spread of 70 fps.
FWIW I find the .30 Carbine and .357 Magnum, despite their difference in bore sizes, behave very similarly and are even at their best with similar powders.