Toby Bridges came up with a method to measure the relative strength of different brands of 209 primers by shooting a patched .32 ball out of an inline without any powder at all, and he then chronographed the average velocity of 5 shots of each. It illustrates that even 209 primers are not all the same:
With a variety of the primers, I headed for the range with the Green Mountain .32 in-line rifle and my chronograph. I started by snapping a couple of primers to get a little base fouling in the bore. Then I wiped the bore with four clean dry patches, exactly how I would wipe the bore between each and every shot. I figured this would give me the same amount of resistance for each and every primer popped behind the well greased patch and light ball. And for each primer tested, I fired 5 shots across the chronograph, then eliminated the highest and lowest velocity readings. The velocities of the remaining three shots were then averaged. And here are the velocities that were recorded for the following No. 209 primers...including the new "Muzzleloading Primers".
Winchester 209ML ........................221 f.p.s.
Winchester 209 Triple Seven ML.....244 f.p.s.
Remington 209 Kleanbore ML ........318 f.p.s.
Remington STS...........................338 f.p.s.
Std. Winchester No. 209A ..............336 f.p.s.
Std. Remington No. 209 .................341 f.p.s.
Cheddite No. 209 ...........................347 f.p.s.
CCI 209M......................................379 f.p.s.
Federal No. 209A ...........................381 f.p.s.
And for comparison, we also ran the Precision Rifle "Vari-Flame" through this test, using both Winchester "Small Pistol" and "Small Rifle" primers.
Winchester WSP "Small Pistol" ........116 f.p.s.
Winchester WSR "Small Rifle" .........143 f.p.s.
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