primer ?

[gordon baxter]

Hi there i have been loading my 270 and 300 mag for years with rem 9 1/2 mag primers and could not get them were im at and got cci large mag primers wondring if they will change my impact point enough to make a difference? Rifles are hunting only. Thanks

[Dan Morris]

Gord, the impact points and groups are definitely gonna change, More important.... pressures are gonna rise! Check your
loading book with charge v/s reg and mag primers...be safe, do not get into trouble!
Dan


BTW...lets hear more from you...you've been a member for a while...get active with us!
:)

[Gil Martin]

I agree with Dan, when you change components it is best to revisit the reloading manuals and work up a safe load. How much will the point of impact change may vary so a trip to the range is in order. All the best...
Gil

[Jack]

Gordon, if I am reading it correctly, you're changing from one brand of magnum primer to another brand of magnum primer.
Just to be safe, I would cut your powder charge 3 grains or so, and work up again. Consult your loading manuals as a reference, too.
My guess is that once you've worked up to the same pressure level with the new primer, point of impact change will be minimal.

[denton]

Not to be crossways with anyone, but...

I have run tests of magnum vs. regular primers, and of Federal and CCI primers in the 243, the 7.62x54R, and the 30-06. In no case did I find any difference in measured peak pressure.

There is a reason the 50 BMG uses a big primer.

But on rifles 30-06 and below, I have searched in vain for a measurable difference caused by primer type.

[Jack]

Denton, I agree with you.
For Gordon, maybe using the same priimer in 270 and 300 Mag saves stocking 2 primers.

[Catfish]

There is reall no way to tell what the presure is going to be till you try, but it could jump a bunch. I ran some primer test with in my .22-6mm with H-870 powder and fired different brands of primers in both regular and mag. I got less than 100 fps. varation between all of the primers. In the same rifle with Mag. Pro powder I switched from Win. mag. primers to Fed. match mag. and the velosity jumped over 200 fps. and the presure became excesive. 1st. rule, be safe.

[dakotah]

Primer shortage is becoming a problem in many areas. Changin components can change pressures. I have not seen this regarding primers as much as cases and bullet manufacture though. I suspect you won't see much difference. However, I would also reduce the load and work back up again. I would do this with change of brass or bullets also.

[gordon baxter]

Thanks everyone i think i might just wait for order of rem primers to come in and buy lots then i will be for a while.