Pressure Signs Help Needed

[Rook57]

Another pic:

Different lots of factory ammo I guess (different head stamps, but both are trophy grade 160 AB)

Both have been fired once as factory loaded ammo, left has just been tumbled, sized, wiped clean, and primed. Nothing has been done to the right.

Note: both have marks and swipes in 6 o'clock position

 

[CatShooter]

Those are NOT pressure signs.

Those loads are fine.

 

[JAYgs8163]

Since we're on the subject. Any recommended smiths that will Bush a Remington bolt/pin? My guy recently retired.

 

[jarnold37]

Using rcbs case lube, but wiping them off with paper towel, and wiping out inside necks with q tips before charging and seating.

Chamber is saami spec

h
Case lube, such as that resembles STP or even wax lube is very slick stuff. Learned something early on in my reloading that the chamber with lubrication, or the case with lubrication, will not allow the case to grip the chamber walls. This thrust is mostly supported by the bolt and is pushed by the head of the case. Take a screwdriver with case lube or stp and try to pick up with two fingers. Think how the tapered cartridge case can "squirt" rearward with no help from the grip of the chamber walls. After sizing I wash the case and the chamber with lighter fluid or solvent. Maybe not the problem you are having but felt the need to share as it not mentioned very often

 

[Mike Matteson]

Hi guys!

Pertinent info:
Rem 700 LH
280 AI
162 ELD-M .020 off lands
H4831

I need help reading pressure signs:

Case on bottom 56.8 grains 2770 fps which should be safe
Case on top 61.5 grains 3041 fps makes me nervous because the Nosler manual says 59.0 is max

Both have ejector marks, help me understand.

Bottom case the primers is shows being okay or that's my feeling. The top the primers is creator which is to hot. Back down the load. Not sure what primer you are using. If you are using a mag primer, try changing to a regular larger rifle primer, but back the the powder down and start up again. Increase your powder load up only at about .3 of a grain. I would only load one case at a time, and increasing the next by .3 over the other one and work back up. Checking your primers on each round fired to see if creating is beginning. Run your finger nail over the fired primer to see if it catches. It might show you a little quicker on the high pressure sign. We know that the 61.5 grains is to hot so don't go there again. The other is how close are you to your rifle landest. That can also create high pressure reading. If your bolt is hard to open generally you are over pressure too. You have a lot of work to go, with lots of trick that can be done to find the load that works best.
That's the fun part of hand loading your own is, because you can change things around to get that grouping, velocity and too how it's doing down range.
If you are loading cases that call out for 70 grains plus to start with, you can generally exceed by .5 grain at a time. Check you primer after each case is fired, looking for the primer is starting to creator. You known you are above what the manual calls out for, be careful.

MAKE SURE YOU KEEP YOUR CASE IN ORDER FROM LOWEST TO HIGHEST POWDER CHARGE SO YOU DON'T GET THEM MIXED UP.

SSS
Mike

 

[Sam Summey]

2.5 grains over max is a mite stout. Is the chamber bright and smooth? Even with the chamber wall fairly straight the AI case may not be clinging to the chamber and loading the bolt face. It maybe being propelled against the bolt face giving the ejector mark. Might try roughing up the chamber a little so the case is stuck to the camber wall a little more. BTW my max load with 140 Sierra is 60.0 grains of IMR 4831. With the 162 gr Hornady 56 gr IMR 4831.

 

[RYEWSKY25284]

Hi guys!

Pertinent info:
Rem 700 LH
280 AI
162 ELD-M .020 off lands
H4831

I need help reading pressure signs:

Case on bottom 56.8 grains 2770 fps which should be safe
Case on top 61.5 grains 3041 fps makes me nervous because the Nosler manual says 59.0 is max

Both have ejector marks, help me understand.

Also, looks like you are getting "cratering marks" on the primer. Is this (162 ELD-m) actually in the reloading manual? If so, I would contact the tech dept. at Nosler. Not intending to disrespect here... but does the manual call for IMR4831 or H4831? It's an easy mistake to make. Hope you get it figured out. Those are significant pressure signs.

 

[Bob Wright]

In my 280AI using new Nosler brass, first time I had a heavy bolt during ladder testing, the primer pocket opened up enough to accept my no-go primer pocket gage pin. Being curious, I full length resized it, but it noticeably was larger in diameter near the head/web section.
I scrapped that piece of brass.
Fortunately my node is 1.5 gr lower at about 3175 FPS avg. Was using 143 Hammer Hunters, RE23 and CCR BR2 primers.
Primer pockets started opening at 3220 FPS and heavy bolt at 3239 FPS.
Nosler brass doesn't like to be pounded repeatedly. Same with my 7mm RM.

 

[robert l]

The cratering from what I've read is from space around the firing pin on Remingtons. Supposedly there's a bushing that you can have fit by a gunsmith. I'm just confused. I guess I'll load to minimum and see what it looks like...

Elk hunter hunter just said that remi 700 all do that to the primer unless they are bushed. I allso do not see any thing that would me back off on the charge.That being said I do not think i would increase the charge. If you are happy with the performance then i think you are good to go ,But i would keep watching to make sure they do not get worse.Good luck with the rifle.And if you are that worried about it then i would have the firing pin bushed.

 

[25WSM]

The Sammi spec 280ai is the same size as the PO Ackley 280ai. They use the same brass and headspace guages. Someone mentioned .014 shorter. This is false. The reason you think it's off is because when Nosler went to get the cartridge Sammi spec'ed they had to use the proper datum line. Po Ackley used a different spot on the shoulder when he measured his. If the Nosler was .014 shorter you wouldn't be able to fire a regular 280 in it. Plus they wouldn't be allowed to call it a 280ai. It would have to be called a 280 improved. When I chamber a 280ai the Nosler brass fits perfect and I definitely don't make my chamber .014 short.
Shep

 

[crazyhorse]

h
Case lube, such as that resembles STP or even wax lube is very slick stuff. Learned something early on in my reloading that the chamber with lubrication, or the case with lubrication, will not allow the case to grip the chamber walls. This thrust is mostly supported by the bolt and is pushed by the head of the case. Take a screwdriver with case lube or stp and try to pick up with two fingers. Think how the tapered cartridge case can "squirt" rearward with no help from the grip of the chamber walls. After sizing I wash the case and the chamber with lighter fluid or solvent. Maybe not the problem you are having but felt the need to share as it not mentioned very often

This is a very important issue that will show itself as pressure when in fact its nothing of the sort! Any lube left on the brass OR in the chamber will cause the brass to flow under pressure creating what looks like pressure signs.

I learned this the hard way one day when shooting a known safe load used in the same rifle many times with zero issues. All of a sudden I'm getting big time extractor marks and really flat primers but no sticky bolt lift. After shooting a couple more and really paying attention to the situation, I noticed all of the brass felt oily. I compared them to the unfired rounds in my box and they were completely dry.
A moments pause caused me to remember cleaning the gun thoroughly after hunting in a hard rain a few weeks previous. I took a lot of care to get oil in every place the water may have got into but wasn't diligent enough to get the oil out like I should have done. After swabbing the chamber dry with a tight fitting, cotton patch wrapped brush it returned to normal with no sign of pressure.

Lesson learned!

 

[Elk Hunter 338]

"""""The Sammi spec 280ai is the same size as the PO Ackley 280ai. They use the same brass and headspace guages. Someone mentioned .014 shorter. This is false. The reason you think it's off is because when Nosler went to get the cartridge Sammi spec'ed they had to use the proper datum line. Po Ackley used a different spot on the shoulder when he measured his. If the Nosler was .014 shorter you wouldn't be able to fire a regular 280 in it. Plus they wouldn't be allowed to call it a 280ai. It would have to be called a 280 improved. When I chamber a 280ai the Nosler brass fits perfect and I definitely don't make my chamber .014 short.
Shep .... """"""

Thats huge negative GHOST RIDER!!! ^^^^^

merry Christmas!!! ^^^^

oh and happy new year !!!! straight off of reddings website!!! and if you need further proof that in fact this is correct i'd call Dave Kiff the one that designed the new version for nosler personally!!!

"""The SAAMI spec cartridge carries the approved name of " 280 Ackley Improved " .
The older wildcat has several names including 280 Ackley Improved 40°, 280 Rem Improved 40°, 280 Imp 40°, 280 Ackley, 280 Rem Imp, and more.
The SAAMI spec 280 Ackley Improved chamber is .014 inches shorter at the datum line headspace dimension than the traditionally accepted wildcat chamber spec as previously produced.
Our current production dies are for chambers that are cut to the SAAMI specification and are stamped "280 Ackley Imp".
Any Redding dies made before 2011 are stamped " 280 Rem Imp 40° " and are built to the originally accepted wildcat specs.
These older dies will not bump the shoulder of cases for a SAAMI chamber. In other words, the old dies are too deep for the current SAAMI chamber.
Redding makes a Competition shellholder that is .014 deeper than the standard #1 shellholder so the owner of a wildcat chamber can use the current SAAMI spec dies for safe resizing.
Failing to use this shellholder or to back the die away from a standard shellholder by a minimum of 0.014" will result in too much shoulder bump which may create an unsafe, excessive headspace condition when fired in a traditionally dimensioned wildcat chamber. """""

 

[freddiej]

Hi guys!

Pertinent info:
Rem 700 LH
280 AI
162 ELD-M .020 off lands
H4831

I need help reading pressure signs:

Case on bottom 56.8 grains 2770 fps which should be safe
Case on top 61.5 grains 3041 fps makes me nervous because the Nosler manual says 59.0 is max

Both have ejector marks, help me understand.

good news is your chamber is on the minimum side, good news, your excessive headspace seems to be at a minimum as well.
bad news is the above means you need to lower your limit for excessive pressure.
Measure a new case and a fired case. this will tell you how much larger your chamber is than you brass. this will tell you how much your brass expands each time you touch off a round. if it is a custom build, I would say it was on the shy side of 0.003" not the standard 0.005" to 0.007" this difference will make the cartridge higher pressure than normal SAAMI spec.

 

[25WSM]

My 280ai reamer is from Dave Kiff. He told me personally that it's exactly the same as a proper 280ai. Which is only .003 shorter than the standard 280. The problem with the Redding story is your comparing apples to oranges. Yes their 280 remington improved is different. But the 280 remington improved is not a 280ai. It doesn't even share the same name. The Nosler is a true 280ai. Same size Po made them. .003 short so that a standard 280 can fit with a slight crush. If it was .014 shorter you would never get a factory 280 in the Nosler chamber. Call Dave he will tell you the same. Who is ghost Rider? My name is on all my post. Don't quote me if you are going to call me silly names.
Shep