300WM Cratered Primers, H1000, 208AMAX

[nwilling]

Hey guys I was wondering if you could all help me figure something out. I'm not really sure what constitutes a cratered primer but I think I've got them, including a little primer flattening. It's a bit surprising to me because I don't think I'm running that hot of a load book wise. According to Hodgdon I should be able to go up to a max of 78gn compressed of H1000 with 208 AMAXs and should see about 2869fps on a 24 inch barrel at 60200psi. Given their COAL is 3.42, and I'm sitting closer to 3.55, at 0.015 off the lands. I worked up to 77.0gn and am getting about 2910fps, but with a 26" barrel. Would you guys say this is unsafe or recommend backing down my load? No other pressure signs except for the flattened primers and cratering...

H1000
Nosler Brass
Winchester LRM Primers
Hornady 208 AMAX

 

[Bigwheels]

What you have there is an oversize firing pin hole with Winchester primers. I have fired thousands just like that , only a bit hotter in my 300WM. I will be making the switch to another primer soon. Win WLRMs have given me problems before, & they wouldn't make it right so I'll not be buying them again. Use the search. There are a lot of threads about them causing problems.

 

[SUIScide]

My primers crater like that too. I don't think your primers are very flattened. Look for an ejector mark or slightly hard bolt lift then back off a bit. What rifle are you shooting?

 

[nwilling]

It's a Phoenix Custom Rifles built on a Surgeon 1086 action. There are no ejector marks and no hard lift. I actually ladder tested all the way up to 77.5gn and nothing seemed any different, I just chose 77.0 because it was in the middle of an accuracy node.

Other than the way it looks though, is this unsafe?

 

[nwilling]

I actually wanted some Federal Gold Metal Magnum Match Primers but they are more impossible to find than H1000.

 

[bkw1911]

I tried winchester primers once recently when I couldn't find federal gmm or cci bench rest and it was a mistake. Several gas blow by's on twice fired Creedmoor brass and 2 pierced primers on a light load. But that's just a side note. Having a nipple on the primer isn't the same as flattened. Every remington get a gigantic tit after every firing.

 

[nwilling]

ah, i figured that flattened just meant that the primer was less "dome-like" the flat section on the fired primer is clearly larger than the unfired, but not much i guess. I'm no rocket scientist but i would think that this is because the primer itself is unseating out the of pocket a tad and flattening itself on the bolt face. Not sure if that's normal but it doesn't sound like it.

 

[nwilling]

http://www.snipershide.com/shooting/snipers-hide-reloading/257024-primer-rupture-help.html

I guess this answers my question, for anyone else's SA when this comes up again in a couple weeks. I normally search, just in this case I have no idea what a primer crater really looks like so I just wanted people's opinions. Looks like I'll have to find new primers... I've heard CCI's have been shit these days, at least from people reviewing them on midway.

 

[sakobob]

try some 210 primers no need for the mag primer. . . . . i was a mag primer guy to,
then i switched, sd dropped and every thing else stayed the same.
you may want to run about 7-10 of those loads pretty quick about a minute or so time frame,
i had that same load and it shot good, but after a quick string i had ejector marks and a firm bolt lift.

 

[nwilling]

Interesting, are magnum primers just hotter to allegedly get a more consistent burn? We're your problems with the load because of the primer or because it was too hot? Thanks for the help

 

[sakobob]

the mag primers are designed to light big powder chargers so ya they are a little hotter,
not all powders need mag primers but some do, h1k didn't.
but i did have to hang fires using rl22 and standard primers. ymmv.
and no the primers didn't cause my 77gr load to be on the warm side, it was just a little to much after a fast string of fire.

 

[bax]

It's a Phoenix Custom Rifles built on a Surgeon 1086 action. There are no ejector marks and no hard lift. I actually ladder tested all the way up to 77.5gn and nothing seemed any different, I just chose 77.0 because it was in the middle of an accuracy node.

Other than the way it looks though, is this unsafe?

Nope, they look fine. I shoot Federal 215Ms, my primers look like that, perhaps a little flatter than yours. Does the gun shoot?

Just FYI, flattened primers are fairly easy to recognize. When you decap them, the corner is sharp (not rounded) and the bolt side of the primer may be spread out to a larger diameter than the "body" of the primer.

Most BR guys shoot their loads pretty hot. One fella showed me his brass, the ridge around the firing pin strike was ... pronounced. When I dragged the fired brass across the back of my hand, primer-side-down, it drew blood. Most of my rounds were not quite that hot.

In my opinion, the Hodgdon max loads are too hot. Others don't think so.

 

[nwilling]

Thanks for the help guys, I'll give the rapid fire a shot and see how the winchesters hold out, will probably get some 210s next to try them out. This site rocks

 

[Xtremegunnr]

I load at 3.685" which is .015 off lands with 77 grains. Anything more and I had pressure signs and crap groups. I get 2830 from a 24" 1-10 bart and 1/4 moa.

Unless you are shooting for a mile + frequently, why kill the brass for a few less clicks on the scope

 

[nwilling]

I am actually looking to stretch it out to a mile, mostly to 1000 though. I got a hold of some 215m primers so we'll see how they work