Mag Primers with Buffalo Rifle or 5744


Well-Known Member
Good evening
Been shooting Buffalo Rifle Powder in our 50-70 and just like 5744 there are always unburned particles in the chamber and barrel.
So as I was blowing out the chamber one time the thought popped up "what about mag primers"?
Anyone given it a try ? I am fixing to load another batch and thought it would be a good question to ask first.


Notorious member
5744 burns like wet rags in a "straight-walled", oversquare cartridge. It won't clean up until well past the safe pressures of your system. Mag primer might shrink groups a bit but that's about it. That said, I've shot some really good groups over the years from a variety of chamberings using loads that left mummies and soot in the bore [shrug].


Well-Known Member
Thank you Ian !
I am thinking load 10 with the LRMP and 10 with LRP and run them side by side with Buff Rifle as we have more of that one.
It is a decent one with a good bore at .515 and clean chamber. Just need to add a ramrod.


High Steppes of Eastern Washington
With 5744, that is always a problem with the newly made stuff. The original stuff from IMI in the 1960's, burned pretty clean.

Clean burning is like chrono data, interesting but not important to group size.


Well-Known Member
I'd only worry about if.
A. I had a lot of vertical stringing.
B. my groups sucked and I had a barrel full of gunk.

I have a shot shell load similar to what some other guy's shoot and it leaves a trail of black stuff all the way from the hull to the target.
many of them get all worked up about it and try all sorts of stuff to fix it.
I just tip my muzzles to the ground after each shot and keep on doing what I'm doing.


Active Member
With new 5744, old 5744, bottle neck or straight, pistol primer to Federal 215 there has always been an unusual amount of residue in bores and cases. I don’t like it but have never seen accuracy issues or accumulating fouling.
Below is the residue from a max load of XMR 5744, RCBS 500gr GC, and Remington 9 1/2 Magnum primers.


  • B177238B-2022-4649-9B90-EC39888FB81A.jpeg
    91 KB · Views: 16

Tomme boy

Well-Known Member
I never have had any unburned powder in several different cartridges. 303brit,7.62x54,303win,3006,3030,350legend. Loaded real light to max. I actually like large pistol primers in the 54r. The gun prefers it


North Central Arkansas
Accurate's data, that I use for my 338W Mag, calls for magnum primers. That's all I ever used..........when I can remember to prime them correctly. I never got consistent groups, with 5744. Much prefer SR 4759. Never notice unburned residue, with either.

Been playing around loading 5744 in my 44 Mag RH. Using Winchester WLP primers. Does pretty good at 60 yards, using a 2X Leupold, off a tripod.


Well-Known Member
It's dirty in my 45-70 but it works great. So I never worry about what's left in the barrel.