Pressure Signs Early/Well before MAX *AND W/Factory Ammunition*

[CouesPursuit]

Headspace check -

Neck sized case.

 

 

Fired (pressured) case, grew 0.0085".

 

 

I'll run a few more cases through the caliper and get them cleaned up for sizing.

[lancetkenyon]

Yeah, you have way too much shoulder bump. You should only have about .002" difference between a fired and a resized case.

[CouesPursuit]

Part of it is from the catered primer.

 

 

The cases with primers less cratered still had .005" or so.

 

 

How do I address this?

[lancetkenyon]

Back the die out .003".

[lancetkenyon]

.005" is not way excessive

[CouesPursuit]

I should have had this comparator and headspace insert long ago. 

 

Thank you, Lance and Lee.

[300RUM]

 

The factory accubond load being hot is interesting. It still seems like there has to be a problem somewhere in the reloads. How are you measuring COAL to lands? I have a Sinclair tool that measures from the base of a bullet seated at the lands then from the base of a fired case in the chamber. Subtract B from A, add the length of the bullet and you have a figure that's based off the actual bullet against the lands and the cartridge in the chamber. If you want to try it that way shoot me a message. I'm in Chandler.

Regrettably, I have been seating a bullet inside a pinched, once fired case into the rifle 3 times and taking an average COAL, then seating down 0.01" from there.

 

I just got my comparator so I'm looking forward to using CBTO from here on out.

 

Thank you for the offer! I will check out the Sinclair tool and let you know if I want to try yours first.

 

It is possible for the bullet to catch in the lands and pull part of the way back out of the case before the entire round starts to move out of the chamber. This would give you an incorrect, long COAL to lands.

[CouesPursuit]

Bringing this one back to the top. After using factory Winchester ammo I had laying around on my WY antelope hunt last fall, my rifle was thoroughly cleaned and put in the safe. I went shooting on Saturday for the first time since.

 

With no real answer to my reloads causing the problems, I started shooting several of the same factory Winchesters with no issue. I then shot 2 Nosler Accubonds and had high pressure problems in both with difficult bolt lift, an ejector mark, and cratered primer on the first and worse bolt lift, ejector mark, and the primer completely blowing out on the second (and last)! I ended with another Winchester with no pressure problem.

The headspace on all of the unfired cartridges is not extreme and matches on all fired brass, growing less than 0.01". The Noslers have a shorter CBTO than the Winchesters and are nowhere near the lands. I'm at a point where I'm going to sell anything I have in the 160gr Accubond and move on, but does anyone have any experience with a rifle hating a particular bullet or other insight? 

 

To recap, my rifle has never produced a major pressure problem on anything reloaded or factory other than when firing a 160gr Nosler AB, and every time that bullet has passed through my rifle (reloaded at starting charge weights of RL23 and H1000 or from the factory) it has caused significant pressure. 

[Hoss50]

Are the cases with pressure problems always Nosler?

I have a Savage in 300 Win Mag that started showing pressure signs earlier then I expected with brand new Nosler brass shooting 208gr ELD-M bullet.

It isn't extreme, but it was a fair amount lower then the "book max" load.

[CouesPursuit]

Not always Nosler.

In my first post, I have a factory Nosler cartridge that pushed a 168gr LRAB without issue and my reloads that had pressure signs at starting charge weights of RL23 and H1000 both were using Hornady brass. Thanks for the thought. 

[300RUM]

I have worked with a number of rifles that hated a particular bullet but it's always been an accuracy issue. I have experience minor pressure differences with same weight bullets from different manufacturers using the same powder but nothing like you describe. If the gun works well works well with other bullets I would just dump those160 Nosler AB's and consider the problem solved.

[win71]

Disagree,Bumping back the shoulder increases headspace. I never ever set shoulders back for that very reason and don't understand why anyone would add headspace. The difference in go and nogo gauges is only .004. The shoulder neck juncture is the holy grail when developing super accurate bench guns doesn't seem it would be any different for what you guys are doing. I have also noticed that Nosler brass has less capacity than say Winchester or Remington. Could be your problem

Dan

[10Turkeys]

One thing that hasn't been thrown out there is your rifle might have a tight neck in it. I've seen it happen it a factory rifle, and so for some reason those Noslers bring it out. Measure the necks of a loaded case, perferably loaded with the Nosler bullet and then measure a case neck from the fired Nosler bullet case, there should be at least a couple of thousands difference between them. Eventuality if you just neck size your brass, sooner or later your brass is gonna stretch and not go in your chamber, if you are hunting that's a problem, if you are at a bench rest match not so much.

[Mike S]

Isn't the head space set on a Savage by the barrel nut? Any chance that has moved?

[CouesPursuit]

1 hour ago, 10Turkeys said:

One thing that hasn't been thrown out there is your rifle might have a tight neck in it. I've seen it happen it a factory rifle, and so for some reason those Noslers bring it out. Measure the necks of a loaded case, perferably loaded with the Nosler bullet and then measure a case neck from the fired Nosler bullet case, there should be at least a couple of thousands difference between them. Eventuality if you just neck size your brass, sooner or later your brass is gonna stretch and not go in your chamber, if you are hunting that's a problem, if you are at a bench rest match not so much.

There is .003 difference.

I have only neck sized this brass and it is 3x fired. I haven't had a problem chambering any rounds. I was going to bump the shoulder back after another firing or two.