Shooters Forum banner

1 - 2 of 2 Posts

·
"Bad Joke Friday" Dan (moderator emeritus)
Joined
·
7,764 Posts
Discussion Starter #1
I have selected the following five small rifle primers for testing with a 6 1/2" barreled .454 Raging Bull:

Winchester (WSR)
Remington No. 7 1/2 Bench Rest
CCI 450 Magnum
CCI BR-4 Bench Rest
Federal Gold Medal Match GM205M

The testing has been performed over a two day period, with five rounds loaded and shot for each primer each day.   The primary interest is the velocity performace and consistency of performance. For the sake of space, I'll only indicate that the cartridge components were Winchester brass (new) trimmed to 1.381", 24.1grs. of W296 powder and a hard cast, gas checked 360 gr. bullet. RCBS .454 dies were used and seating and crimping were done separately.  O.A.L (1.777") was compared between both groups to assure consistency.
The temperature was 72 and 74 degrees.

                            Average Velocity
Manuf.        6/28        6/29         Combined
Win            1338.6    1332.8      1335.7
Rem           1353.6    1344.2      1348.9
CCI 450     1337.2    1330.6      1333.9
CCI BR-4    1354.0    1329.2      1341.6
Fed            1353.4    1327.0      1340.2


                            Extreme Spread
Manuf.        6/28        6/29         Combined
Win              42           23                42
Rem             20           37                40
CCI 450       16           37                37
CCI BR-4      17           13                40
Fed              32           24                48


                            Standard Deviation
Manuf.        6/28        6/29         Combined
Win            15.25        8.70           13.44
Rem             7.58       12.92          12.22
CCI 450       7.19       12.32          11.19
CCI BR-4      6.10         4.45          14.23
Fed             11.72        8.72          17.67

At this time, my conclusions are:
1. interesting how two groups loaded exactly (as best
   I could) the same, varied as much as they did. I
   suspect this suggests a 5 shot test is too small a
   quantity and the 10 shot combination is more
   representative.

2. no primer stood out as far as velocity/consistency
   performance is concerned.

My next test will use the same material/process except I will place the cartridges in the freezer (0 degrees) for 2 hours and then transport them to the range in an insulated container with ice.  Not the most accurate process, but I'm going to Florida in the winter so this is the best I can think of.  I'm open to suggestions, please.

I also collected accuracy data while performing the tests and the results clearly identified a problem -- ME!  Iron sights and my eyes/talent didn't give very consistent results. To get more meaningful data, I will run an additional 3 tests of 5 shots each and then compare the five separate results.  

Respectfully

Dan
 

·
Registered
Joined
·
252 Posts
Dan,
Outstanding Post!!!!  I'm really looking forward to the results of your cold-temp tests.
Good shooting
Mark
 
1 - 2 of 2 Posts
Top