Primer substitute

[Chas.]

I have read that the main reason for not using pistol primers in rifle cartridges is because rifle loads reach much higher pressure levels and may rupture the thinner pistol primers.  I've also read where recommended loads for .480 Ruger handgun reach 46,000 psi pressure range using large pistol primers (from Accurate Powders website).  That being the case, large pistol primers must withstand at least 46,000 psi pressure.

Now, to my question.  If my 45-70 loads are well below 46,000, say 28,000, is there any reason I can't use large pistol primers?  Being a straight wall case, it's actually just a giant-size pistol cartridge anyway.  I have a bunch of large pistol primers but large rifle primers are all but non-existent around here.

[pourboy]

Large pistol primers use a shallower cup than large rifle primers. Pistol primers will most likely seat deeply enough in the case that your firing pin might not strike them hard enough to give reliable ignition. You might get lucky though.

[bilmac]

I have a Marlin 30-30 that hits the primers very light. It misfires pretty regularly with rifle primers, but goes off most of the time when I use Mag pistol primers. I use mag primers because I have been led to understand that standard primers might be a little weak .

[LaOtto222]

Large pistol primers are not as "tall" as large rifle primers so they will set below the level of a rifle primer when fully seated. We are only talking a few thousands, not enough to make much difference unless your firing pin does not come out far enough to make a good dent in the primer to start with. I think Large pistol primers will work for your application - depending on the powder type you are using. If it is an easily ignited powder (not a ball type powder) and you keep your pressures low, I think they would work. In a 22 Hornet I use small pistol primers instead of small rifle primers. I get lower pressures with the same powder charge. I do not think the "spark" is as strong in the pistol primers so it effects pressure, but in a lower sense, not higher. The real proof is to; load some up and give it a try. Be prepared to tear down your loads if you get pierced primers - but I expect you will not have problems as long as you do not get pressures very high. I expect you will get lower velocity/pressure with the same powder charge comparing Large pistol primers to Large rifle primers - but again the proof is in the shooting. Good Luck and Good Shooting.

[huntswithdogs]

My Brotherinlaw has used Mag Pistol primers in his Contender(35 Rem) since right after he got it, back in the mid 80s. Rifle primers weren't going off regularly(lite strikes) and a friend of ours told him to try the others. The friend had come about the same problem when he got his Contender barrels (45/70amd 35 Rem).



HWD