Are These Pressure Signs or Just My Rifle?

[DMW1116]

I loaded a couple of loads for my 30-30 and tested them a few months ago. I then set it aside until I could get different sights. I went and tested the sights and tried to zero with the 160 gr FTX load yesterday to no avail.

I came back and checked brass to see the primers seemed to be slightly proud of the pocket. No flattening, no sticky bolt, or other sign I’m aware of. These loads had been shot before and I don’t remember this being an issue.

Both loads show the same issue. One is a 110 grain FMJ load with a minimum charge of H335, 34 grains. Hornadys data shows a starting charge of 34.1, and my Lyman manual started at 34. These are Hornady bullets.

The other load is a 160 gr FTX over 34.7 grains of LEVERevolution. This is within one grain of the 2200 fps load shown in Hornadys data, which is 34.8 grains. The max is a whopping 37 grains.

I need to fire a couple factory rounds and see if they have the same issue. Both loads are having accuracy issues so I was going to test one more time and decide whether to pull and redo both loads or just learn to shoot better.

 

[edwardware]

It's a frequently asked question.

 

[sequins]

Lower pressure loadings won't fully press the primer back into the pocket on firing. Typically this is a sign of low pressure in my experience, as is dirtier cases from poor ignition at the same lower pressure.

 

[tightgroup tiger]

It's a frequently asked question.

Lower pressure loadings won't fully press the primer back into the pocket on firing. Typically this is a sign of low pressure in my experience, as is dirtier cases from poor ignition at the same lower pressure.

Correct.

 

[DMW1116]

The load I’m using for the FTX bullets is pretty far from minimum. Could it still not make enough pressure to push the case back?

 

[bullseye308]

First thing I’d do is clean the barrel thoroughly, then up the charge closer to the middle of the range, then try some factory and see how it does. Kind of like starting with a clean slate, then see what your loads do. Like mentioned above, primers backing out are from too light of a load.

 

[stringnut]

30 30 headspaces on the rim. Not uncommon to have a bit of excessive headspace and a large chamber. This , coupled with being a low pressure cartridge, will cause primers to back out. What happens is the case is driven forward by the hammer dropping, the charge fires, the case expands enough to grip the chamber walls, and the primer has enough room to back out a bit. This is according to P O Ackley. He proved that a model 94 Winchester could be fired without the locking lugs and the action would remain close. I don’t remember the details ,so, wouldn’t recommend trying it at home!

 

[WestKentucky]

Correct.

That’s my #1 and #2 criteria for load development. Primer should be seated properly and the load should burn fairly clean. Clean normally happens after primer seating except for in 5.56 cases that have had pockets reamed. Seems that reamed pockets are ever so slightly looser than stamped pockets that were never crimped.

 

[DMW1116]

I don’t see any excess dirt or soot on the cases for either load. I intend to redo the 160 FTX load. I don’t have powder or bullets for the other 110 grain load. The low pressure could explain why these two loads were fairly erratic accuracy wise as well. Other than the 110 grain FMJs, projectiles aren’t terribly hard to come by. More annoyance than anything. I have several questions to answer for this rifle. Hopefully I can scratch out some better accuracy. Otherwise I may have just wasted my money in a peep sight. Both these loads shot considerably better with factory sights. That might just be my expectation though. I typically do better with peep sights than I did with these two loads yesterday.