Sensitivity Between Federal Primers

[Alaskan454]

Some time ago I remember reading a statement that Fed. magnum primers were just as sensitive as the standard ones.  I recently got a chance to load and test Fed. 100, 200, and GM100M on the same day.  I had run approximately 1,300 rounds loaded with GM100Ms without any misfires while the action was set to 4.75 lbs.  That was in temperatures from 30 to 80 degrees between 5 different days and I didn't clean the gun at all during that time.  I've shot enough of those to feels pretty confident in the ignition.

I cleaned the gun before its next trip and shot only Fed. 100s and had one light strike out of 240, after examining the case it was one with a crimped primer pocket so I think it didn't get seated far enough on my press.  The session after that I had a mixture of loads and shot 100 rounds with the Fed. 200s, I was getting 3-4 light strikes in each cylinder at 4 lbs 12 oz and slowly increased the mainspring tension until I could fire 8/8.  It ended up around 5 lbs 5 oz on my digital scale, I'm guessing it needs to get bumped up just a touch to be 100% with the 200s but I ran out of test loads.  I don't really plan on using these in my 929 but was curious if there was a difference and if so how much.  Thought I might share this info in case anyone was wondering or needed to swap for magnum primers in a pinch.  

[Kurusty]

Thank you for the info. Did you happen to chrony these? I only ask because I never noticed more than a 10-15 fps difference between the magnums and standard. I never had any issues because I run my triggers at 6-1/4.

[alecmc]

From my understanding.

 

The Fed 100 & Fed 100GM are the same exact primers, difference being the 100GM primers go through an extra step of quality control.

The magnum Fed 200 primers are harder to set off, but if you do run your trigger heavy enough to set them off you'll likely yield another 40-60 FPS out of your load velocity. 

 

No reason to buy the magnum fed200s, just go with the standard 100 series. 

Edited December 14, 2016 by alecmc

[RevoWood123]

Considering the looming panic has now farily well subsided, hopefully the return of abundant primer resources is not far off. It will be wise to purchase often and build a solid reserve, even if you feel no urgency (when they do return). We still have about 150 cases of the 100s and GM100s on order that we placed this year (we had 4 whole cases arrive the other day, hopefully the rest aren't far behind).

A454, thanks for sharing your information as always. I was testing with some of the Federal GM200s last year and found about what you did, they did need to be hit harder. On chrono, mine only averaged about 30 FPS different (4" barrel).

[Alaskan454]

I didn't get a chance to chrono the different primers so I'll do that next time I load up some 200s.  It's nice to know for future reference if I need to use them in a pinch.