Looking for more info on CCI 450 Mag primers vs the 400 SR primers I have been using....Lapua br, 105 Berger HT, for 6mm Creedmore. Using 40.4 gr R16 powder....which I currently cant find anywhere!!!
6mm CM CCI 450 Mag Primers
- Thread starter jmcampbell1066
- Start date
You would be so much better off loading 10 of each, conduct your own test, shoot 5 for group, chrono the other 5. I can give my opinion, but a friend just ran this same test in a 6GT. Substitute 205M for the 400, more speed, better numbers, better groups. Not the same case though, but in his test it all pointed to a more efficient burn.
I wouldnt use the 400s in anything larger than 223 (and I recently started popping 400s in that too).
Stick to the 450s, they are a thicker material to stand up to the pressures and then have a bit more oomph for more consistent ignition reliability on all that powder.
Or try a fgmm 205m or a rem 7 1/2 primer.
Stick to the 450s, they are a thicker material to stand up to the pressures and then have a bit more oomph for more consistent ignition reliability on all that powder.
Or try a fgmm 205m or a rem 7 1/2 primer.
As you can see, they're a little thicker which helps with cratering and/or piercing. I was experiencing both when working a load up for my 6creedmoor w/400's at nowhere near it's pressure limit (something to do with the RPR firing pin). Once I switched to 450's it went away and I was able to work up a successful load. An alternative are the CCI BR4's but they are more expensive and are essentially the same as 450's.
Also, Reloading Unlimited has R16 in stock...
Hope this helps
Also, Reloading Unlimited has R16 in stock...
Hope this helps
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Hey @spife7980 , imagine seeing you here in this thread! Yep, I found the hard way that there is a major practical difference between 400s and 450s when I started loading .223. In over four decades of handloading pistol cartridges, I never encountered a significant practical difference among primers. I just used standard primers in everything, including .357 and .44 magnum, and never had any issues.
So, when I simultaneously began loading .223 and small-primer'ed 6.5CM, I ordered a few thousand CCI 400s for the former and CCI 450s for the latter.
I found that even the lightest, mildest loads listed on the Hodgdon site and elsewhere gave me severely flattened CCI 400 primers, although velocities were comparable to those shown for the published recipes. Only then did I pay attention to the primers specified. Hodgdon was showing Winchester SRPs, the other ones Remington 7 1/2s. Note the cup dimension differences in Spife's table.
So, now I'm allocating the 400s mainly to pistol loads. I can't speak to CCI 400s in any caliber but .223 but, for me, they suck in .223. I have a thread here somewhere in which I asked whether the badly-flattened (never pierced, just flattened) primers constituted a potential danger. Whether they do or don't, I don't like seeing them flattened to the point of flowing out of the pocket with mild-moderate loads.
So, when I simultaneously began loading .223 and small-primer'ed 6.5CM, I ordered a few thousand CCI 400s for the former and CCI 450s for the latter.
I found that even the lightest, mildest loads listed on the Hodgdon site and elsewhere gave me severely flattened CCI 400 primers, although velocities were comparable to those shown for the published recipes. Only then did I pay attention to the primers specified. Hodgdon was showing Winchester SRPs, the other ones Remington 7 1/2s. Note the cup dimension differences in Spife's table.
So, now I'm allocating the 400s mainly to pistol loads. I can't speak to CCI 400s in any caliber but .223 but, for me, they suck in .223. I have a thread here somewhere in which I asked whether the badly-flattened (never pierced, just flattened) primers constituted a potential danger. Whether they do or don't, I don't like seeing them flattened to the point of flowing out of the pocket with mild-moderate loads.
Do a little searching and find a zillion posts about the similarity between CCI 400 SR and CCI 550 SPM. You'll find posts - albeit old -about conversations with CCI showing they are indeed very very similar. Other posts will detail how a big primer in a small cases is not optimal."... allocating the 400s mainly to pistol loads."
Is this a typo, or a bit of wild-catting? Just checking.
I suppose there are a very special few pistol calibers that use these primers....
Using the 400s in pistol ammo is not something I'll do unless there is no other choice. But that statement applies to using 400s in .223 unless I have a need for spitwad velocities.
No problem with cci 400 in 223. I'm running 25.7gr tac, horn brass, cci400, and 69gr tmk. Gets me 2890 in a mk12 clone.
As to op question, I use cci 450 in lapua brass, 105hybrids, and 41.4gr rl16. It runs 3130fps and primers are perfect looking. Shot in a 6creed origin.
As to op question, I use cci 450 in lapua brass, 105hybrids, and 41.4gr rl16. It runs 3130fps and primers are perfect looking. Shot in a 6creed origin.
Excellent. I've tried H335, IMR-4895, and (finally settled on because available) CFE223.
Here are twice-fired rounds (Defender brass) - same load, three with 400s, two with 450s. I forget the exact charge of which powder and my content list doesn't go back far enough, but it was nowhere near max.
That's flat, lol.
Here is 5 of the 69tmk cases. There is some ejector mark's, but that was from previously fired with a can. I need to look at an adj gas carrier.
Here is 5 of the 69tmk cases. There is some ejector mark's, but that was from previously fired with a can. I need to look at an adj gas carrier.
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