Primers

[NightStalker]

I havent got my reloading book for Grendel yet, but am wondering what primers I should be looking for.
I like Rem 71/2 SR for 223, can I use this for mey Grendel?

[grayfox]

Rem 7 1/2. yes, Rem 6 1/2 or lower, no.
cci 450 are the ones most used.
BR-4.
cci41, WSR small mag,
Fed 205 AR. 205M in bolt guns. cci 400 can go into a bolt gun also, the slam fire from a floating pin is not so much a concern in bolt guns.

Problem with cci 400 and Rem 6 1/2 (and a couple others) is they have cups that are too soft/thin so slam fires (floating AR firing pins) can occur.
Which you don't want your face to encounter...

[Mark611]

The last time I reloaded for my 6.5grrr AR I used Winchester Standard small rifle primers and I did not have any issues at all but I did seat them 4k into the pocket, and I fired 60 rounds, This is using a Sanders side charging upper with a standard AR 223? buffer and spring, is this dangerous?

[mdram]

all i was able to find was federal match ar, i think its GM205MAR

[Mad Charlie]

all i was able to find was federal match ar, i think its GM205MAR

Unless I am using ball powder, that is the primer I most use.Ball powders get 7.5's or 450's.

[Harpoon1]

I havent got my reloading book for Grendel yet, but am wondering what primers I should be looking for.
I like Rem 71/2 SR for 223, can I use this for mey Grendel?

[Texcl2]

+1

[adamkrog]

Unless I am using ball powder, that is the primer I most use.Ball powders get 7.5's or 450's.

Why not use the Federal with ball powder?

[bamban]

Why not use the Federal with ball powder?

Nothing wrong using 205MARs igniting ball powder. Granted it does not get that cold where I am, I've only used them in high 30s with no drama.

Let me add this. When I shot a lot of 308s with small primer pockets in my double lug M1As, I used CCI 41s when they became available, 450s before that. Larger case capacity need the flame, small match primers can't deliver. Case capacity under 30 grains the 205MARs will do just fine.

[grayfox]

Most of the federals have a lower fire, or brisance, and ball powders are harder to light, so the combo is not the best recommended.

[Mad Charlie]

Most of the federals have a lower fire, or brisance, and ball powders are harder to light, so the combo is not the best recommended.

Thank you.
I have found, over the years, that I get better velocity consistency with mag primers/ball type powders. Stick type powders seem to like a softer ignition. This is only my experience and observations, nothing scientific about it at all. Others may have the exact opposite results, that's just fine with me. Whatever works is whatever works.

[StoneHendge]

Federal 205 M and 205 MAR have the highest brisance of any non magnum small rifle primer. Google "small rifle primer brisance". I can't get a chart to cut and paste. The GM205MARs are exactly the same as GM205M inside, the AR just has a thicker cup. I use them both interchangeably.