Hello folks,

I just came back from the range today after doing some load testing. My all around hunting load for this year is Winchester brass, WLRM primers, 73.0gr of RE-15 and 260gr Accubonds. I shot this load in 28 degree Celsius temperature without any problems at all, no heavy bolt lift or hard extraction.

I decided a few days ago to try out some CCI250 primers. Using the same brass, powder, bullet combo, I started loading some Winchester brass that was on its 3rd reload. Reducing by 5%, I loaded one round with 70gr, the next at 71gr, 72gr and so forth all the way up to 73gr or RE-15. These are the observations 15' from the muzzle:

70gr: 2616 FPS
71gr: 2633 FPS
72gr: 2666 FPS
73gr: 2700 FPS

The 73gr loads were showing a slight bolt lift, but hard extraction. I had to pull fairly hard on the bolt handle to get the case out. I examined the cases and did not notice any overly flattened primers, or any other signs of overpressure. Primer pockets are still very tight... I added a few picture so that you can see for yourself. You will notice the area just above the belt where the brass was sticking. Most of you will probably tell me to back off on the powder charge since its a sign of over pressure. The velocity is not over book velocity by any means!!! I'm just wondering if any of you had such problems in the past? By the way, commercial ammunition extract without a glitch.

By the way, this load does shoot very well... 3 shot group at 100 yrds!

cases read 375 HH, but not stated

of the 4 cases shown, 3 have a strong RING about 40% of the way up.... you want to do a wire test for case seperation or slap the gunnie that ringed your chamber

looks like you are overly resizing your cases, stop full length resizing

Pressure should not be excessive for your .375 H&H load. Moderately warm not excessive.
I use a reference of max load (trouble free) for my rifle:
300-grain old Barnes X-Bullet
seated to 3.600" COL
F215 primer
WW brass
RL-15 72.0 grains
24" barrel velocity (12" twist): 2530 fps

Chamber ring mid case body?

Improper headspace with excessively sized brass can do funny things like incipient case head separation and sticky extraction.
Even on a belted case if belt is set back and headspace is excessive. Have you measured your belts after three firings and resizings versus the factory/new brass?

The factory ammo must be a better fit.

No RIP, I never measure the belt itself after three firings... I will do that.!

quote:

Originally posted by jeffeosso:
cases read 375 HH, but not stated

of the 4 cases shown, 3 have a strong RING about 40% of the way up.... you want to do a wire test for case seperation or slap the gunnie that ringed your chamber

I think those rings are from the plastic MTM box. They do that to my brass too. Insipient case head separations would normally be lower.
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"Serious rifles have two barrels, everything else just burns gunpowder."

The first thing I would do is cut one of those casesm in half length wise and see if those rings are the beginning of insipient case seperation. If so then I suspect your chamber is a tad long and the fireforming process is putting a strain on the brass..Also I would check the headspace, it boils down to a process of illimination.

If this is not the case then change back to the original primers or reduce your load a grain or two.

First off, let me thank everyone who replied. All the information gathered is great! Such a wealth of information on this forum!!!

I reloaded 5 rounds today using the same brass. W-W brass that was on its 4th reload, WLRM primers, 73 Gr of RE-15... COAL of 3.590"

I did call Nosler technicians today to talk about the problem. He suggested that my brass was maybe not being full length resized enough and that the brass was not springing back. I decided to readjust my resizing die and screw it in 1/8 of a turn more. Loaded 5 rounds, and drove to the range. Temperature was 10 degree Celsius, wind was calm.

I only had 2 cartridges loaded with the CCI 250 primers so I elected to fire them down range. Same as yesterday, nice groups but sticky cases. I elected to shoot my 5 newly reloaded rounds and to my surprise, no heavy bolt lift, and no sticky cases...

As for the rings on the cases, well, they don"t show up on once fired brass... Looking in the cases with a light source I see no thinning of the case walls... Anyway, I thought I would upload a few pictures taken today at the range. It sure looks like I have my minute of moose down pat

Thanks again for your input,

Maurice