Is a Primer a Primer a Primer?

[RyanM]

Very interesting. Has anyone done a similar test on pistol primers? I may have to switch to Remingtons in my carry loads, since then I'd have absolutely no worries about ignition!

 

[EShell]

Slamfire . . .

Using CCI #34 in .308 match loads, I found it impossible to get decent accuracy that was much more forthcoming with regular WLR primers and the same set of components. This may be due to the hotter mix being incompatible with the medium-capacity of the .308 case, since #34s are most similar to CCI #250s, but less sensitive in order to be compatible with military auto and semi-auto firearms. I had been trying to find a load that would "work" in both my M1A and my M-700 LTR . . .

I cannot explain it. I have been using CCI#34's in my M1a's and 308 bolt guns. And I have been getting excellent results. I use IMR 4895, or I am going through a batch surplus 4895. When I chronograph the stuff, velocities are not all that different from WLR.

LOL, that IS tough to explain - I'm using MilSurp 4895 myself, and didn't have any better results with commercial.

I'm loading FGMM brass ('cuz I have a gazillion) and Lapua 155 Scenars. I shoot a lot of long range, and one of the tactical matches I shoot requires a .308, of all things. FGMM 168s don't reliably stay stable to ranges beyond 800-900 or so in my 20" LTR, and FGMM 175s drop ferociously (43 MOA to get on at 1k from a 100 yard zero) and drift is almost as bad. The Scenars have the same BC as the 175 SMK, but can typically be driven 200 fps faster, making them THE bullet to use in Ol' Stubby, IF I can get them to shoot. I ran into light pressure indications at 42.0, some 3-4 grains below book max, and am holding at 41.5. Did some research and found the #34 to be equivalent to CCI#250s.

FWIW, I just found out that my lot of MilSurp 4895 is terribly temperature sensitive with my combo and I will have to abandon it for my match ammo anyway. Loads worked up during moderate weather (60-70oF) used about 4 more MOA to be zeroed at 1k or so when used at 30oF. Putting some of the ammo in my pocket as an experiment gave me *FEET* of vertical at extended ranges compared the ammo carried awhile in the rifle.

Still, I miss the old nickle plated WLR. That was a great primer. Wish Winchester had not changed them. They also changed the WSR. That primer pierces so easily. I still have a stash of them, and used them to load my short range ammunition at Camp Perry this year. The same load will pierce at least new brass WSR per relay. The old primer, not a single pierced primer for the entire National Matches.

I used to use the old WLRs myself, and still have a few hundred *old* ones around. I haven't have any problem with my new ones (brass-plated cups), and use them in my daughter's .243, my .260 and 6.5-284 match rifles. Using match-prepped Lapua, Rem & Norma brass, respectively, I typically get light ejector marks (M700s), then hard extraction before seeing a lot of primer flow.

Guess these are excellent examples as to why it is always prudent to work up to max using your own components, rather than taking someone else's data, no matter how trustworthy or reliable the source.

 

[rbernie]

Small Rifle 

       Cup Thickness Diameter Height 
CCI 400 .	.020"	.1753"	.109" 
CCI 450 .	.025"	.1750" 	.113" 
CCI BR4 	.025" 	.1755" 	.109" 
Federal 200 	.019" 	.1757" 	.111" 
Federal 205M  	.0225" 	.1744"	.1075" 
Remington 6 ½	.020" 	.1753" 	.109" 
Remington 7 1/2 .025" 	.1752"	.110" 
Winchester SR	.021"	.1750" 	.109" 

Large Rifle 
       Cup Thickness Diameter Height 
CCI 200 	.027" 	.2112"	.118" 
CCI 250 	.027"	.2113"	.118" 
Federal 210 	.027" 	.2120" 	.117" 
Remington 9 1/2	.027" 	.2100" 	.119" 
Winchester LR 	.027" 	.2114" 	.121" 

Brand/type	      Power Average Range    Std. Dev
1 Fed Match GM215M	6.12    5.23-6.8   .351
2 Federal 215 LRM       5.69    5.2-6.5   .4437
3 CCI 250 LRM            5.66   4.5-7.4   .4832
4 Winchester WLRM      	 5.45   5.1-6.0   .2046
5 Remington 9 1/2 LRM    5.09   3.5-6.75   .6641
6 Winchester WLR         4.8    4.1-6.0   .4300
7 Remington 9 1/2 LR     4.75   3.7-6.25   .5679
8 Fed Match GM210M       4.64   4.0-5.6   .3296
9 Federal 210 LR         4.62   3.7-5.5   .3997
10 CCI BR2               4.37   4.0-5.0    .2460
11 CCI 200 LR            4.28    3.8-4.8   .3218
12 KVB 7 LR Russian      4.27    3.8-4.8   .2213
13 Rem 91/2 (30 yrs old)  4.16   3.8-4.8   .3427
14 Rem LP                 4.47   3.2-5.6   .5171
15 KVB 45 LP Russian      3.89   3.3-4.2   .2232
16 CCI 300 LP 	         3.18    2.7-3.5   .2406
17 Federal 150 LP        3.11    2.6-3.5   .2090
18 Fed Match GM150M  	 3.05    2.6-3.7   .2299

 

[FLORIDA KEVIN]

I wonder if it would be of any value to get some of those rubber x-ring bullets that fire using just a primer for power .load several cases with different primers like , small rifle ,small pistol. magnum and non magnum and fire them through a chronograph to determine the relative power of each type ? I would try it but i dont have a chronograph !

 

[Slamfire]

rbernie: Very interesting chart. Assuming that this chart was conducted on the new "brass" Winchester primers, the large rifle cup thickness is the same for them as for all.

Which means that if the new Winchester is more sensitive and more prone to piercing than CCI, then Winchester took the workhardening out of their cup, or maybe that nickel coating makes a difference.

And Remington 9 1/2 primers are the strongest of the standard primers and CCI are amoung the weakest. I would not have thought that.

 

[rbernie]

I should qualify - this is not my data, but a compilation of what I've found on the web.

 

[scout26]

Just in case someone comes across this thread and is considering shotshell reloading.....

Shotshell primers are VERY different and cannot be wantonly interchanged. You must follow the published recipe and use the primer call for.

Now back to the Rifle and Pistol primer discussion.

 

[Wildfire]

Slamfire1

Forget about what brand of primer you are using. Slamfire1 in post 17 cover'd it well. Headspace ? Firing pin protrusion ? I agree. No firing pin bounces off a primer. The fact that some primers may be hotter or more touchy is not the issue. The fact is your gun is not working right. Atleast not all the time.

 

[rg1]

Remington 6 1/2 primers are for lower pressure 22 caliber rifles. The primer cup thickness on 6 1/2's is supposed to be .020" while 7 1/2's cup thickness is .025". Use 7 1/2's especially in semi-autos.
http://www.jamescalhoon.com/primers_and_pressure.php