Primer Testing Reference
Retrieved: 08/27/2016
This testing was done to try and rank primers by power (brisance).
This is the home made tester. The shot is fired against a weight which in turn moves a pointer. The pointer remains at the highest point of the shot.
This shows the pointer after a shot has been fired. In this case, it was a Federal large rifle magnum
NOTE: This data is reference only. This is on a DMS (don't mean squat) scale. It is relative to this set of tests and this tester. Take them with a grain of salt and as a guide only. Most of the tests were of 100 or more primers. A few were of 50 when limited amounts were available.
Ranked in order of power
Large Rifle = LR, Large Rifle Magnum = LRM, Large pistol =LP
Brand/type Power Average Range Std. Dev
1 Fed Match GM215M 6.12 5.23-6.8 .351
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
Pistol primers
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
This is a retype after losing the original web page. I did not put in the
individual comments. Note the spreads. The Rem's had some very wild shots
high and low. CCI BR2 and the Fed 's were the most even of the common ones.
The new Russian were very even, but this was a limited lot and they are not
widely available.Weighing Primers: I did some test weighing and found the bench rest had virtually no variations. Of the others, there WAS a relation between weight and power. Those extra heavy tended to be stronger, and light were weaker.
Firing pin strength also seems to be a definite factor. Stronger hit is probably more consistent. This has been noted by some sharps shooters when they break a firing pin. It will still fire, but they get fliers and open groups.
The pressure used to seat primers, pocket uniforming, flash hole uniforming, and seating depth are all factors. Keep them all the same.
Another thing that is not in this test, but I have noted, is using a newsprint wad over the primer. This keeps grains of powder out of the flash hole. It seems to even out the ignition by eliminating a variable (sometimes with grains in and sometimes without grains in, or a variety of combinations).