Primer change in Marlin 1894C loads

[chg]

Finally got my Marlin 1894C after 7 or 8 months of searching. It's a fun rifle and I've been enjoying it this past month.  I was in town last week and decided to try and get some more small pistol magnum primers to keep this new toy running.  Went to two stores and came out empty handed.  Third store had a thousand PMC Small Pistol Magnum primers. The only metallic cartridge primers in the whole store. There were 5 or 6 thousand shotshell primers on the shelf but just that one brick of small pistol mag. So I'm standing there looking at this box that says "Heavy Metal Free, Truely Non-Toxic, Non -Corrosive, Made in Russia" and I'm thinking - Here I am standing in downtown Lewiston, Idaho - home of the good ol' boys - CCI/Speer, and the only primers available in three different retail stores come all the way from Russia.  Something is not right. The Non -Corrosive made me feel better, the "Truely" Non-Toxic didn't do a thing for me and at least it didn't say Made in North Korea. Any port in a storm - RIGHT?  I bought them, paid almost what a carton of 5000 would have cost 18 months/2 years ago and limped out the door.

I dropped my usual load back a 1/2 grain and loaded 50 with the CCI 550, H110 and #358156 Lyman.  I did another 50 with the new primers, same powder charge and boolit.  My thoughts were, well, if this brand is available and CCIs are not, I'll work up a load with it and go with what's available.  Set up the chronograph and ran the CCI 550 primed loads through first.  Average velocity 1779 fps with an extreme spread of 25 fps.  PMC primed loads next with an average of 1581 fps with an extreme spread of 121fps one barely broke 1500fps- same powder charge, cases, and Lyman's #358156. Only difference was the primer.  200 fps difference seemed unreasonable so I tried it again, 5 shots per load with the same results.  When I got home I pulled a bullet from each and weighed the charges thinking the CCI loads were my regular charge and not ones which I'd reduced a 1/2 grain like the PMCs.  Both charges were the same weight.  I've never chronograghed loads like this where the only difference was the primer and it made 198fps difference in that rifle.

 

[454Puma]

So got that extreme spread with a .5 gr less powder charge? Are you loading a starting load for H110?  H110 needs to be a close to max as you can for your rifle for the best results!   I use the Silohete loading in Speers #13 manual for my loads with this powder. Get low ES.

[chg]

It was a starting load listed in Lyman's 48th handbook. I dropped back because of the component change.  The 50 rounds loaded with the CCI 550s were an afterthought, a day shooting, had the Marlin out and just 50 would not last long, already had the powder measure set and just continued with the same charge, not my regular one for that cartridge.  The chronogragh was along for two other rifles not the Marlin.  Like I said, everything fell in by chance far as chronograghing these loads.  Was totally amazed at the velocity differences brought on by just a primer change.  Everything else, crimp, caselength, case mfg. etc  was the same.  I repeated it with only 5 shots each just to verify the first results. 

[dpe.ahoy]

Sounds like time to up the charge and try again.  They might not be as hot as the CCI, and with the lower powder charge, not getting a good ignition.  I have found the same as Puma454 said, H110 needs the pressure to burn correctly.  If you have any, try LilGun in the 357, I have started using it for all my 357 rounds.  DP

[Lloyd Smale]

primers can definately make that much difference in velocity. I had a case of wolf large and small mag pistol primers and they were about as hot as a standard fed primer. I lost an easy 200 fps in some loads. the wolf standard primers were very week. I ended up using the mag pistol primers to replace primers in loads that used standard primers. I believe the wolf and pmc were made in the same factory so im not surprised your getting simular results

[retmech]

I noticed in my .357 rifle and handguns that winchester primers in most cases gave less velocity than Federal or RP.  The worst case is with 12.5 gr of 2400 behind a cast 170 gr. SWC out of my Rossi single shot rifle with 24" barrel. All my data is for 10 shot strings.  WW primed load 1560 fps avg,ES-127 fps,sd-42 fps.  Federal primed load, 1662 fps avg, ES-51 fps, sd-14 fps.  Primers do make a difference!