Primer help

D

Dano4734

New member
Ok I have 100 empty 45-70 buffalo bore brass. However, the Buffalo bore 8b uses a magnum primer. All my reloading books have a large rifle primer in their listings. I am sure the load data would have to be adjusted some how or am I wrong
 
So is 45 grains of h322 under a large rifle cci the same as a magnum primer
At least I assume that is what they use as a cci 200 will not fit but does fine in the Remington brass I have
 
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The only time I would use a magnum primer in the 45-70 is if I was hunting in below freezing temperatures.

I know you stated that you were going to visit daughter in Alaska and hunt there, so how cold is it gonna be when you visit?

That should be your decision maker.

Personally, where I hunt, it seldom gets below freezing and I use mostly CCI200 in just about all rifles that I load, but not all. And, it depends on the powder too, referring to ball powder.

My favorite powder is IMR4198. The makers had a statement on the IMR website that IMR 4198 was tested from -40 Deg F up to 125 Deg F. for temperature stability and it exceeded their expectations.
 
I really don’t want to use magnum primers but i hate to toss the buffalo bore brass. Their bass will not seat a cci 200. Their 45-70 magnum brass looks like it will only take a magnum primer.
 
Just found out they use sterling brass and small rife primers in their magnum 45-70 405 grain bullets ugh.. I wondered how they can push over 2000fps apparently so to control that load. Going to toss them. They special order the brass from starline
 
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There seems to be some confusion here about primer sizes and standard vs magnum primers.
There are small and large rifle, and small and large pistol. The external dimensions of the small primers are identical (sp & sr), as are the large (lp & lr). The biggest difference in those are cup material thickness/hardness and charge strength. Within each size, say large rifle or small rifle, there are standard and "magnum" options. Again, these are dimensionally identical, with differences in cup thickness and charge potency.
If I understand you, Buffalo Bore is using Starline Small Primer brass, so you should just be able to use a small rifle primer, and can use a magnum small rifle primer for higher pressure resistance. CCI 450 should be the small rifle magnum primer.

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"Their bass will not seat a cci 200. Their 45-70 magnum brass looks like it will only take a magnum primer."

magnum large rifle primers have the same external dimensions as standard large rifle
 
The 40 pieces of BB brass I have uses small rifle primers. I use standard small rifle primers in them, as I have not loaded any on the extreme end. The brass I have I picked up 4 or 5 years ago when a guy shot two boxes, and left the boxes with the brass on the table when he left.
 
I'm a little confused here. All large rifle primers are the same diameter and some may vary a few thousandths in length. All small rifle primers are the same diameter. The only difference is size is the large rifle primers are .008" taller than large pistol primers. Does Buffalo Bore have a propriety sized primer?
 
The idea of reloading with small rife primers doesn’t sit with me. If you want the brass just send me an address and I will give them to you. Oh I have 60 of them or so
 
Again buffalo bore uses small rife primers that they special order brass from starline. I was confused as when I tried to seat a large rife primer it didn’t work. Now I know why
 
Dano the small rifle primers are due to the fact that when loaded hot they do not back out as easy as the large ones do. The ones I cull to the side are Hornady. All of their brass is shorter than the rest. This is due to the Lever Evolution bullets being longer. So they make the brass shorter to compensate for that. They work just as good as any. You just have to set the seating die lower to crimp them. Then remember to reset it to higher so you do not crush a long case next time.
 
Sounds like you found your answer. Small primers present a smaller area to the pressure, so the force tending to back them out is almost a third lower. Magnum small rifle primers have thicker cups than standard small rifle primers, so they resist mushrooming and flattening and cratering and piercing better than standard or large primers. So these cases are designed to tolerate higher pressures before they show pressure signs at the primers.

So, you might ask why that is necessary when plenty of large magnum rifle cartridges operating at even higher pressures don't do that. I believe the answer is that higher pressure 45-70's are often fired in lever guns, like the Marlin 1895, which have a rear locking lug. As pressure gets higher in these guns, the sides of the receiver start to stretch back because of the force the bolt puts on the locking lug. This can bounce, momentarily opening up a few thousandths of a gap between the case head and breech face on the bolt for a fraction of a second. Because the gun is at near peak pressure when that happens, they need the extra resistance of the stubby primer to prevent expanding and piercing during the bounce. Mind you, this is really only an issue at pressures that are right up against the limit for the gun.
 
Magnum primers are about the powder used. Regardless of the size. No need to adjust the data according to primer size.
Buffalo Bore 8B ammo is nothing more than a Max load. Most likely of H4198. No magnum primer is required for H4198. You'll note Buffalo Bore does not publish the pressures of their loads. Hodgdon shows their Max load for a jacketed 400 grain bullet(close enough to 405.) runs at about 39,400 CUP. SAAMI doesn't list CUP pressures for .45-70. And there's no mathematical formula to convert CUP to PSI.
No mention of them using a small rifle primer on their site either.
 
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