I am using Norma .300 win mag brass. I have uniformed the primer pockets all the way meaning my redding uniforming tool is bottomed out. I am loading with federal 215m primers and seating with RCBS seater tool. I squeeze the tool all the way down like I have done in the past with all other calibers and brass. First of all the primer pockets seam very tight. But after my second reload on this brass and second time bottoming out my redding uniforming tool the primers stick protrude a couple thousands above the head of the casing. I am unable to get an accurate distance from base to ogive and also my ES is not as good as I would hope for where every other variable is uniform. I am not saying this is the cause of my large ES but it is a possibility. All I know is this is not right and have never experienced this in the past. What can I do about this? Is it possible my 215m primers are longer than normal. I have tried 215 and 215m primers and both protrude from the case.
Primers not flush
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cjjkels
Member
never loaded Norma brass but did have a problem with 300 win mag.I used RCBS 90201 prime tool and had trouble but switched to the bench mounted 09460 and now no trouble.If that's the one your using, then I don't know. My brass was win but really tight primer pockets.
It is the rcbs hand tool. It is putting some pressure behind the primers because I can see where the rod is putting dimple around the edge of the primers. It seams as it the primers are bottomed out or if the sides of the primer pockets are tapered and once they get down to a certain depth they wont go any more and never reach the bottom of the primer pocket. I would assume this would explain the high ES.
geargrinder
Well-Known Member
Fed primers are soft. You might not be seating them hard enough. Seeing the dimple is very common.
I encountered this with Norma brass twice and Nosler brass once. I now use a RCBS primer pocket uniformer with a chordless drill and a tiny bit of water as a lubricant. Also make several cuts brushing off cutter with each cut.
7stw
Well-Known Member
I agree with AZ, I have seen this before, and the cutter is the cure. I use a Sinclair pocket unifomer, and it works great. That's unusual for Norma brass though. One other thing you will notice about Norma brass, is that if you use a flashole reamer, you will get a little resistance with the pilot, as the factory hole is much smaller then the domestic brass is. I meant to say flash hole deburring tool, rather then reamer.
It could be that the pocket bottoms are just rounded on the edges, so the uniforming tool may only do a partial cut. As AZ said, clean it frequently when doing the cut.
SidecarFlip
Well-Known Member
This sounds inane but are you sure you have the rod in the right way? The RCBS tool's primer seating rod has a wrong and right way to be installed.
I just set 215M's in 338 Nosler brass with no issue.
I just set 215M's in 338 Nosler brass with no issue.
I had a lee uniformer, that wasn't doing it for some reason so upgraded to the redding and that still isn't working. If I had to guess I would say the pockets are tapered for some reason and not getting all the way down. What can I do about this? Call Norma?
Varmint Hunter
Well-Known Member
I had a similar problem but was seating primers with the RCBS press. I tried changing brass, primers and technique before nearly giving up. I determined it was the press by giving a few pieces of my brass and primers to a buddy and asked him to seat the primers. Every one of them seated normally in his press. I replaced the priming apparatus and never had a problem since.
My guess - undetected tool problem. Probably seating the primers at a minute angle, thus causing the problem.
My guess - undetected tool problem. Probably seating the primers at a minute angle, thus causing the problem.
If our OP was using a RCBS rock chucker press with priming arm I would say to check to see the cup is tight. They will unscrew over time. Takes a pc of metal the dia of a needle to fit the tiny hole to tighten.
Perhaps the hand priming tool has a similar way to tighten the seating cup?
Perhaps the hand priming tool has a similar way to tighten the seating cup?
Are you using a primer pocket cleaner or a primer pocket uniformer?
SidecarFlip
Well-Known Member
I use the same seater tool as you so I was just asking. Not trying to insult. I've installed mine wrong end up before.
It's possible to determine in the pocket is tapered but I don't think so. I believe whats occuring is the pocket isn't quite deep enough for the primer brand you are using (remember that all primers aren't the same height, they can actually vary by as much as 7 thousands in cup height from brand to brand and even vary lot to lot in the same brand).
I found that out with my CVA muzzleloader when I shimmed the firing pin retainer. I had a pack of CCI 209's and bought 1000 Federal 209's. I set the retainer for the Federals and the CCI's would not allow the breech to close due to the cup height difference. Incidently, slamming the breech closed on a shimmed CVA with a high primer insures a misfire.....FYI.
You can have the same issue in a rifle primer, if the pocket depth is on the shallow side and the cups are on the high side, you'll wind up with the primer face proud of the cartridge face, no matter how hard you try to seat the primer. It only goes so far and it hits the bottom of the pocket. Thats it.
My suggestion is try a different brand of primer and see if the seated height changes or mike your primers and compare to another brand...
Norma produces good cases but like Lapua, the tolerances are tighter than run of the mill brass.
I realize primers are a bit tough to get right now, but I believe thats your issue.
