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300 WSM loose primer pockets - need some help please

screamrider

Well-Known Member
Joined
Aug 20, 2012
Messages
45
Location
California
Well, after safely shooting my first batch of reloads I'm hoping folks can help me out with a little problem I encountered.

Full disclaimer, this was my very first batch of reloads and I'm a total newb. I did a ton of research and reading before loading, so first I'll lay out exactly what I did:

Rifle: Browning X-bolt stainless stalker, 300 WSM
Cases: Once fired federal premium factory ammunition, nickel plated
Primers: Winchester WLRM
Powder: H4350
Bullet: 180 grain TTSX

1. I cleaned the cases in tumbler
2. I lubed the cases with Hornady one shot
3. I resized and deprimed the cases in my Redding press with a Redding deluxe FL die. I set the die so that the shoulder was bumped back 0.002 inches (using Hornady head space gauge).
4. I tested the empty cases and they chambered with no issue.
5. I trimmed the cases to exactly 2.0900 with the LE Wilson micrometer trimmer
6. I chamfered and deburred each case with the LE Wilson hand deburring tool.
7. I cleaned the cases in the tumbler again.
8. I hand primed each case using the RCBS universal hand primer. ****At least half the primers went in with extremely little effort, while the rest had just a bit of resistance.
9. I loaded three cases at each of the following weight: 60.0, 60.5, 61.0, 61.5, 62.0, 62.5, 63.0, 63.5, 64.0. I used the RCMS chargemaster combo.
10. I seated the bullets with my Redding deluxe seating die with a 0.050 jump off the lands (using Hornady OAL gauge).
11. OAL was between 2.860 and 2.865 for the 27 cartridges I made.

So, off to the range I went yesterday with my 27 handloads and 5 federal premium factory loads, in 180 grain trophy copper (my rifle shoots these very well).

First 2 rounds at 60.0 were good to go, with expected velocities of 2743 fps. Then on my third 60.0 round as I was sliding the bolt forward I noticed there was NO PRIMER in the case!! I immediately thought back to how easy it was to hand prime and thought that it must have just fallen out. I looked around and sure enough it was sitting on the bench beside my rifle.

I cautiously continued to fire my rounds, but only after tapping the bottom edge of each case on the bench to make sure no other primers were going to fall out. I didn't have another one fall out, but on several of my higher loads (63.5 and 64.0) I noticed carbon residue around the primer itself, telling me that they were not a tight fit and there was some gas leakage.

Bottom line, I got 2 solid groups from my hand loads, the best being 0.30 inches at 100 yards with 63.5 grains.

I am not concerned with the loose primer pockets and have the following questions I'm hoping I can get some input on:

1. When I researched the loose primer pocket problem I read that federal factory brass have unusually large primer pockets, and that Winchester primers (the uncoated brass ones) are unusually small, making my combination a recipe for primers falling out. Any truth to that or others with similar experience?

2. I think that it's possible the federal premium factory rounds are too hot. They were shooting 3044 on my chrono and muzzle velocity is supposed to be 2960. I also think the enlarged primer pockets could be a pressure sign? I've also spotted some case head extrusion marks on the once fired brass, and some slight rim bending on a few cases. Has anyone else found this with federal premium ammo from a 300 WSM? Potential issue with my rifle?

3. Since there was some gas leakage around the primers, would this reduce my handload velocities, or make them erratic? My best load at 63.5 grains measured velocities of 2879, 2886, and 2892. Is this a reasonable velocity distribution?

4. The only primers I can find within 2 hours are the Winchesters. I have WLR and WLRM. I used the WLRM for these loads. I'm thinking about ordering some Norma 300 WSM brass and will stop using the federal I have. Anyone know if the WLRM primers will fit better in the Norma brass? Any other brass recommendations?

That's all for now, I really appreciate any help you can offer!

Sorry for the long post, but I hope it lays out all the pertinent facts.
 
Federals WSM loads are pretty hot. The nickled brass is pretty soft. I tried to reload them once. Just once and never again.

Not what you want to here but dump the Federal brass and get some Winchester or Nosler/Norma brass.
 
I will add this...I have reloaded now for 7mm rem mag, 3006, 300wsm, a bunch of pistols and revolves and my 300wsm has had major issues with loose primer pockets even after only one firing. Magnum rifles tend to get loose pockets well before non magnums BUT dang...even after only 1 firing some of my wsm brass has loose pockets. Never had that problem with my 7mm rem mag yet.
 
Too bad about the federal brass. I just ordered some Norma so hopefully that works out better for me.

Will changing the brass typically have a significant impact on the loads? For instance, 63.5 grains of H4350 in the Federal brass gave me a great group. Should I go back down to min load and work my way back up with the Norma brass?
 
Winchester primers can be a little "small". If you can, try some CCI to see if they are any better.

Also, I get much better accuracy with standard primers in Short Mags.
 
Winchester primers can be a little "small". If you can, try some CCI to see if they are any better.

Also, I get much better accuracy with standard primers in Short Mags.

I was wondering about that as I've read conflicting reports. I do have some Win WLR primers so I'll try those. I can't find any other primers around here to save my life.

Curious why the difference between standard and magnum primers?

Also, can I expect standard primers to change the velocities of the loads I've already tried, just curious and trying to learn?

Appreciate your help.
 
Too bad about the federal brass. I just ordered some Norma so hopefully that works out better for me.

Will changing the brass typically have a significant impact on the loads? For instance, 63.5 grains of H4350 in the Federal brass gave me a great group. Should I go back down to min load and work my way back up with the Norma brass?

Yes, different manufacturers' brass, and even different lots from the same manufacturer, will vary in capacity, affecting pressure. When working with max loads, the rule of thumb I use is to reduce the load by 5% when changing components, and work back up, purely for safety reasons.
 
Yes, different manufacturers' brass, and even different lots from the same manufacturer, will vary in capacity, affecting pressure. When working with max loads, the rule of thumb I use is to reduce the load by 5% when changing components, and work back up, purely for safety reasons.

Will do, thanks Bill.
 
You have gotten some good advise, especially from Bil Johnson. I have loaded 300WSM brass from many companies and they are different. Norma brass in my opinion is the best short mag brass. I have some that have been reloaded 10+ times and the primer pockets are still tight. The problem with the loose primer pockets on once fired brass comes from two things. One Federal brass is soft and prone to loose pockets and the second thing is factory loads are very hot!
When I fired my first 300WSM Winchester factory load it was too hot, bolt almost too tight to open.

Norma brass is heavier than Winchester brass(I have not compared it to Federal) and therefore the volume of the brass is less. Work up the load and you can fire many rounds without loose pockets.
 
You have gotten some good advise, especially from Bil Johnson. I have loaded 300WSM brass from many companies and they are different. Norma brass in my opinion is the best short mag brass. I have some that have been reloaded 10+ times and the primer pockets are still tight. The problem with the loose primer pockets on once fired brass comes from two things. One Federal brass is soft and prone to loose pockets and the second thing is factory loads are very hot!
When I fired my first 300WSM Winchester factory load it was too hot, bolt almost too tight to open.

Norma brass is heavier than Winchester brass(I have not compared it to Federal) and therefore the volume of the brass is less. Work up the load and you can fire many rounds without loose pockets.

Sounds like a plan, I should have the Norma brass within the week.

Any advice on the WLR vs WLRM primers?
 
I was wondering about that as I've read conflicting reports. I do have some Win WLR primers so I'll try those. I can't find any other primers around here to save my life.

Curious why the difference between standard and magnum primers?

Also, can I expect standard primers to change the velocities of the loads I've already tried, just curious and trying to learn?

Appreciate your help.
My favorite primer for the WSM is the Fed 210M. I'll use CCI 200 if I have to May BR2s and BR4s would serve my uses better if I can't get Federal Match.

WLR/WMR are fine but like I said, seem to show "loose" before the others. I do use them on one load specifically because they are "softer" than the CCI.

I noticed almost no difference in velocity between regular and magnum primers in the WSM. The powder column is short enough that the standard primer makes plenty of ignition.

I think and for lack of better words, the magnum primer excites the powder too much. Like pinging in an engine. You want one smooth flame path.
 
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