Pressure signs with factory ammo

Bob Wright

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Jan 23, 2018
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Litchfield Park, Az.
Hot day can cause a load that is just below it's max pressure to go over pressure. Nosler brass is known to be soft and can be short lived.
Recheck your COAL, any jamming possibilities, etc.
If you have a carbon ring, get to work on that. That can drive pressures way up due to it restricting the bullet release.
I would call Nosler and ask them if there are any pressure related issues they know of and give them your lot numbers.
After all this, if Nosler says their ammo is not recalled etc., you might try chilling your ammo and shoot one, then reassess the brass for same condition. Chilling to about 50° F should lower the pressure for a simple test.
Otherwise, buy a good manual or get lots of loading data from bullet manufacturers, powder manufactures and buy different brass. Then start your reloading journey right here.
Something isn't right with these loads and how its reacting in this rifle and outside temps. You'll find it. Ask for help.
 

100percent

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Jun 5, 2019
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MS
For the record, I had two boxes of Nosler factory ammo for 7stw that blew pierced primers. For reference, chronographed 160 accubonds at 3660fps. Crazy hot!!! I called cs and they asked me to send them back and I did. I asked for my money back or a store credit at midwayusa. Still have the two boxes they replaced them with! Anybody interested in buying those??? Nosler brass is great but, no factory ammo for me!
coal was not a concern in this case as the factory ammo was jumping .17 thousandths
 

manitou1

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Mar 27, 2012
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Missouri
I have quite a bit of Nosler brass in 7mm08 and .280 Rem that has been fire six and seven times and still going. All loads near max. I found Hornady brass to lose primer pockets pretty quick.
 

243winxb

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Sep 9, 2016
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USA
Enlighten me why can’t you use a firing pin sized to the hole instead making the hole smaller never could figure that one out. David
Good guestion. Maybe an expert will answer, then we will both know.:)

On 22 lr rim fires, a reshaped, smaller area pin nose applies more energy in a given area. The depth will be deeper. More energy in a smaller area. I feel this helps when brass is on the hard side.
This reshaped pin can move the impact area off the solid part of the rim.

But on center fire, a larger diameter pin would increase the impact area. The primer may absorb to much energy over a larger area, causing misfires??

A Larger diameter pin & heavier spring would work, but it may cause a BR rifle to move more on firing.
On smaller cartridges(223), the pin impack may set the shoulder back on firing. Head to datum shorter by .006" till pressure expands the brass again.

If i was the OP, put some factory ammo in a cool box before firing. See if air temperature makes a difference.
At 65,000 PSI, things are going to flow. Rifles that work at this pressure range may show primer flow & ejector hole marks.

The question is, when is it to much?

On right, ok. On left not ok. Far left, primer fell out.
Ejector Mark.JPG
 
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twister

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Jan 18, 2018
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The 26 Nosler you traded for - custom rifle, or factory?
Though not impossible, it would be unusual for a factory rifle shooting factory rounds to show this.
I have a 6mm Creedmore that does this when i shot a box of the berger 105's ammo for the brass. so not that uncommon i guess shoots the hornady stuff fine though.
 

Tex_Hunter

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Feb 26, 2011
Messages
197
Like the title says factory ammo, I do have questions related to reloading though. Little background, very new to reloading, I’ve successfully made a few hundred .223 & .308 lately just tryin to learn the basics. The issue/questions are about a 26 Nosler that I traded for. It supposed has low round count but who knows. Came with 80 rounds of 140 ab and 60 of 142 ablr. I have had it quite a while but had only shot a few rounds through it about a year ago and didn’t think much about it. So forward to now and with the limited knowledge I’ve gained (a lot of it from this site) made me question what I saw yesterday from this factory ammo. First picture is the 142s, second the 140s. The 142s cbto averaged 2.706, the 140s 2.766. I pulled one of the 142s to measure with, I was surprised how scared it was when I did, I’ve only pulled a couple .223s that I’ve loaded,they didn’t look like this (3rd pic), had 71.1gr of whatever Nosler loads. So using the Hornady tool jammed all the way I come up with 2.839 and just touching 2.703. This is where the questions start, I’m unsure of my process measuring, jammed all the way seems simple enough, just touching much harder to be consistent. I started out yesterday with a clean, pretty close to bare, dry bore and chamber. All rounds resulted in stiff bolt lift, not have to death grip or pick up the rifle but definitely stiff. Would it make sense to pull/reseat bullets in the factory ammo for some jump ? Or dump the powder and try something different ? BTW velocity average was 3251 and of the powders listed in the Nosler manual 71.1 should be pretty mild. With a bore scope I can see what maybe a carbon ring starting ? after 15 rounds that wasn’t there when I started. Am I overthinking this ? Couple years ago I’d have looked at the brass and thought that’s weird and kept right on stuffing and shooting, lol. Any advice is appreciated. Hope the pictures load, my sat internet is pretty lame.
The firing pin craters, in absence of other major pressure signs isnt really concerning. All it really means is that there is a loose tolerance between the firing pin and the hole in the bolt face. The ejector swipe on the fare right piece is concerning, and you said you also had heavy bolt lift... had the rifle just been cleaned before these rounds were fired? I've had heavy bolt lift and major ejector marks on brass from VERY mild factory ammo on a fresh cleaned rifle that had just an ever so slight amount of oil/solvent in the chamber, get a chamber swab and put a little gun scrubber (or electrical contact cleaner, something that degreases and then flashes off an leaves no residue)and give it a good swab to make sure the chamber is spotless, then re-shoot.

the 26 Nosler isnt exactly a pussycat to begin with, and Nosler factory ammo is on the warm end of the spectrum in my experience. I had some of their 308 Ballistic tip factory ammo that was right on the edge of their own max book data based on the velocity I was getting (2815fps with a 165gr ballistic tip from a 26" barrel). If cleaning the chamber and re-shooting still yields heavy bolt and swipes/cratered primers, you may want to shoot something else out of it.
 

tyleray

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Dec 15, 2018
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Location
Utah desert
This right here is the first thing I thought of:

had the rifle just been cleaned before these rounds were fired? I've had heavy bolt lift and major ejector marks on brass from VERY mild factory ammo on a fresh cleaned rifle that had just an ever so slight amount of oil/solvent in the chamber, get a chamber swab and put a little gun scrubber (or electrical contact cleaner, something that degreases and then flashes off an leaves no residue)and give it a good swab to make sure the chamber is spotless, then re-shoot.
 

73driver

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Aug 24, 2011
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256
My newer factory MOD 70 270 shooting Nosler loaded ammo gave me over preassure signs on a normal temp day.
 

ofbandg

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Jul 26, 2015
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I have been to the range with a couple friends, both of whom have the same rifle in 28 Nosler and they experienced stiff bolt lift with factory ammo. The flow back might just be the heat and the borderline hot factory ammo working together. It is possible to encounter factory ammo that is hot all by itself. I was given a box of 250 grain Federal ammo in .338 Win. one time to try out and it rocked me pretty hard with flow back and flat primers so I cronographed it and got 2850 fps. That's about a 100 fps more than I had ever got with that bullet weight before.
 

Indian7953

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Feb 15, 2015
Messages
131
This right here is the first thing I thought of:
I had a Remington 700 in a 7 mm short action ultra mag that did that with factory ammo when it was brand new. I called Remington and they said to send in the ammunition for testing, then they told me to send in the rifle to be checked. They found out the rifle head too much headspace and replaced it. The new rifle still did that on the first two or three shots after being cleaned and then settled down. It might be a good idea to have your rifle headspace checked.
 

milo-2

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May 1, 2011
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Gillette, Wy
Enlighten me why can’t you use a firing pin sized to the hole instead making the hole smaller never could figure that one out. David
I actually did this on a Stiller Predator action, 6.5x47 Lapua case, so small primer.
I wasn't rupturing or cratering primers, it was piercing them. It was mild load, and long before the pin hole hole bushing craze hit. It worked fine.
In my experience, firing pin tips are soft, the more they are subjected to cratered or pierced primers, the more damage done to it and things only get worse. Most all of this as been eliminated by action companies going to small holes, tighter fitting pins. Though I do have one Impact 737 that craters my Dasher brass, i have no idea why, 7 firings on the brass and pockets still tight. My smith has new firing pin for me, but I am going to wait till I rechamber to swap it out.
 

WYO300RUM

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Mar 23, 2011
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Wyoming
I have same problem with a factory Cooper Mod. 52 in 6.5x284. factory HSM 140 Berger VLD and Factory Norma 156 Oryx. Ejector swipes and heavy bolt lift. Mid range reloads same thing. I can seat bullets way out there and same thing. Neither , factory or reloads near rifling . No carbon ring. I don't get it. Tight chamber?
Tired of messing with it. My Ridgeline in 6.5 PRC I haven't even reached pressure yet . It loves 156 Berger's.
 

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