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Best 7mm mag primer

This thread gives me hope to try out some standard primers until I can get a decent supply of magnum primers. Lately I've been shooting more ball powders because they're so easy to use. Just spot check charges in the loading block and seat bullets. So with ball powders I'll probably stick with magnums, especially in the winter. But if extruded powders work okay with standard primers I can suffer through hand trickling my charges. Great information! Thanks for sharing.
 
What seems like a long time ago I bought primers by the brick. At the time I thought that made sense from a cost perspective. I don't mean I have dozens of bricks of primers or anything like that. I just mean that's how I bought them. I never thought lack of availability would be a thing.
 
This thread gives me hope to try out some standard primers until I can get a decent supply of magnum primers. Lately I've been shooting more ball powders because they're so easy to use. Just spot check charges in the loading block and seat bullets. So with ball powders I'll probably stick with magnums, especially in the winter. But if extruded powders work okay with standard primers I can suffer through hand trickling my charges. Great information! Thanks for sharing.
Some "ball" powders like the Accurate line in the mid burn rate range really aren't hard to light. Others, like 50 cal. ball offerings (8700, us869, etc.) probably ought to have a mag. primer if you have any real case capacity... When in doubt, I'll hit them a bit hard, especially living in N.D. as the temp. gets below zero during hunting season at times.
 
Some "ball" powders like the Accurate line in the mid burn rate range really aren't hard to light. Others, like 50 cal. ball offerings (8700, us869, etc.) probably ought to have a mag. primer if you have any real case capacity... When in doubt, I'll hit them a bit hard, especially living in N.D. as the temp. gets below zero during hunting season at times.
I'll be loading mostly 180 Gr bullets so slow burning powders on my list.
 
I too have read or heard somewhere that the Mag primers are designed primarily for heavy charges of ball powder and a 60 gr charge was the "suggested" cutoff for reg/mag primers. Consequently, I use CC BR-2 for all cartridges less than 60 and Fed 215 for all over that. A tad arbitrary but one less thing to "wrassel" with, kind of like the ubiquitous 1000 Ft pound rule at point of impact for big game. As Forrest Gump would say, "one less thang"...
Just looking for better accuracy out of my Tikka T3X 7 mag.
 
I recently tested this in my 7 saum. I was using CCI250/175 EH/63.5 gr N565 with really good results but wanted to see if a primer change would make a difference. So comparing Fed210M vs CCI250 in that combination made no difference in average velocity or group size, however significantly lower ES/SD. ...
Which of the 2 gave you "significantly lower ED/SD"?
 
I'll be loading mostly 180 Gr bullets so slow burning powders on my list.
One of the loads we run in our tikka 7rem is aa8700 and a 175 hornady... With the 9.5" twist this rifle needs a flat base pill but wlrms light the fire just fine. It's usually around a 1/2 moa rifle running this combo, but the recoil is a bit stiff for my 14 year old. H870 and wc 860, 867, or 872 mil-surp powders would work great with the 175-180 also.
I have been running 68 rl22 lit by a 215 with a 140 Sierra pro hunter for a mild recoiling load right at 3,000 fps, but recently picked up a bunch of Long Rifle powder and worked up a mild range load at 58 grains Long Rifle with a wlrm and a 140 Sierra pro hunter to punch paper with. I suspect this is only 2800 fps or so but the kid needs trigger time on the rifle he'll hunt more than he needs speed. I also suspect that a regular wlr would do just fine here and possibly be a bit faster as I might still get accuracy at a bit higher charge.
 
Some "ball" powders like the Accurate line in the mid burn rate range really aren't hard to light. Others, like 50 cal. ball offerings (8700, us869, etc.) probably ought to have a mag. primer if you have any real case capacity... When in doubt, I'll hit them a bit hard, especially living in N.D. as the temp. gets below zero during hunting season at times.
I ran US869 in my 338-416 Rigby Improved 45° at 127g with 210 Match primers without issue, even at -2°C.
The only time I had issues was with a frozen firing pin from moisture, the primers would fire when the bolt operated correctly…I stopped putting my bolt in my pocket after that incident. Lost a really good deer because of this too.

Cheers.
 
I have always been able to get good results in the 7mm Remington Magnum and the 7mm Mashburn Super Magnum with Federal 215 or 215M primers using powders as fast as the 4350s and as slow as Retumbo or RL26. I lean toward the heavier bullets in the 160 grain and up range.
 
Use what works the best.

In my 300PRC F Open gun. I originally started with Fed210M primers. I switched on a recommendation from Dave in the shop to try CCI200's as that's what he was using in his 300WM. My SD's and ES numbers dropped quite a bit going to the CCI200's. and I'm running 76gr of H1000 behind a 230gr bullet.

A mag primer isn't necessarily the best.

Yes there is the old rule of thumb of when you go over 60gr of powder to switch to a mag primer. Or depending on the type of powder or temp conditions you should be using a mag primer as well.

Later, Frank
Bartlein Barrels
 
That would be a very warm temperature during much of our big game hunting seasons. Now a -2 F, would be more temperature appropriate ……with -20's, not unheard of! memtb
Yup... -2C isn't that cold. My brother will probably be hunting in shorts and crocks at that temp.. I've hunted in weather that'll freeze your spit. During muzzy season one year I lost a deer because the lube I had in my inline gelled up and the striker didn't drop. Lesson learned, only synthetic lubes on hunting guns in the field now.
 
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