Pressure signs not showing at Max load

[Mc Fraser]

In my opionion, you can see pressure signs. I will be very careful about going forward ...
My 300WM with 28in barrel gets constant pressure signs 1-2 GR below what the box says its max.

 

[MOOSE39465]

Every newer remington will crater primers like this. For some reason they bevel the firing pin hole. OP please post a picture of your bolt face.

Here you go thanks. That's after 25 rounds.

 

[bdcoon]

If you develop your load correctly temperature shouldn't change your POI dramatically. The OCW method of load development is a way to make your load more stable.
In order to detect any pressure signs you have to have a baseline to compare your visual assessment on. As for the primer cratering, that could be common to that particular rifle. How do the primers look at a lighter charge? The still rounded edges of the primer is what I am looking at. I'd be more concerned if you had a flattened, extruded, or pierced primer. Definite pressure indicators.
Also I don't believe that the slight imaging of the ejector shown is a valid pressure indicator. I would expect a more visible image as a pressure sign such as a raised bump on the case head from the extractor.
From my experience almost all manual recorded maximums are well below the actual maximum pressure of most rifles. This is a liability limit by the manufacturer. I have reloading manuals from various bullet manufacturers (Hornady, Speer, Nosler) from 50+ years ago that have max loads for the same bullet/powder combination several grains higher than that of the latest manuals.
Here is a good article on reading pressure signs. http://www.massreloading.com/reading_pressure_signs.html

Helpful information, thanks for posting.

 

[MOOSE39465]

Moose, I'm loading for the same exact rifle, but different recipe. FYI, I hit pressure early (I think so??) with RL-16 also. 42.7 grains, and I got slight ejector marks and the group opened way up. 42.2 grains shot less than 1/2 and inch and the brass looked perfect. Max charge was supposed to be 43.4; I didn't even bother to shoot the last group. Hope this helps...

Nice group. What FPS are you getting with rl-16?

 

[MOOSE39465]

Besides group, which if it's good. what was the velosity? Was it where you want it for performance?

I didn't bring my chronic on the last trip. I will have it next trip.

 

[MOOSE39465]

If you develop your load correctly temperature shouldn't change your POI dramatically. The OCW method of load development is a way to make your load more stable.
In order to detect any pressure signs you have to have a baseline to compare your visual assessment on. As for the primer cratering, that could be common to that particular rifle. How do the primers look at a lighter charge? The still rounded edges of the primer is what I am looking at. I'd be more concerned if you had a flattened, extruded, or pierced primer. Definite pressure indicators.
Also I don't believe that the slight imaging of the ejector shown is a valid pressure indicator. I would expect a more visible image as a pressure sign such as a raised bump on the case head from the extractor. My edit: Another indication of excessive pressure is a "sticky" bolt.
From my experience almost all manual recorded maximums are well below the actual maximum pressure of most rifles. This is a liability limit by the manufacturer. I have reloading manuals from various bullet manufacturers (Hornady, Speer, Nosler) from 50+ years ago that have max loads for the same bullet/powder combination several grains higher than that of the latest manuals. You need to know what you're looking for in reading pressure indicators. And I'm not advocating that it is safe to exceed recommended maximums. I'm saying if you choose to do so you need to approach cautiously, in small increments, examining each and every fired case.
Here is a good article on reading pressure signs. http://www.massreloading.com/reading_pressure_signs.html

Thanks for the advise

 

[Havard]

Nice group. What FPS are you getting with rl-16?

That's a good question; I need a chrono

 

[codyadams]

If you think that's max, you haven't been to max

Anyways its possible you could find another good node at 42.5 or so but I wouln't mess with it. I have a long throated Tikka and load to 2.925 and 43.2. That same load is unsafe in a normal; chamber.

I have blown primers before going too far, I absolutely know max ha ha.

The next steps are shiny ejector marks, then heavy bolt lift, then more extreme of those same issues, carbon blowing around primer, and full blown primer. I have seen cases where the difference between a blown primer and pressure signs as he is displaying has been only 1.5-2 grains, and others where one day loads like he displayed were acceptable then another hotter day or a round left in a hot chamber caused heavy bolt lift and primer pocket stretched enough to no longer hold primers securely, especially in soft brass such as hornady. I'm sure you know all this, it isn't really for you it's just for general information and topic discussion.

Loads like he has there may be acceptable for hunting, where one to three shots is all that is generally fired, especially if he is hunting in cool conditions, but the trade off will likely be brass life. That load would be a poor choice for extended shot strings. And loading up higher certainly won't reduce the already existent pressure signs, they only get worse from there.

 

[coyotezapper]

Rifle-Remington 700 6.5 Creedmoor
Bullet-142 Grain Accubond long range
Power-H4350

Went to the range today and done some load development. I was pleased to see my rifle really liked the Accubond long range bullet. When I got to the max load on the Nosler website I examined the cases and was surprised I didn't see any pressure signs. My question is what now? Should I just start increasing to powder charge until I see ejector marks or stop at max? I posted a picture of a case so you could see for yourself.

What was your velocity??

Velocity = Pressure

 

[JASmith]

Maximum suggested loads are just that, Suggested. They are intended to be safe in different rifles. The fact that you are not seeing pressure signs is a good thing. The only thing to do at this point is to run them through a chronograph to verify the velocity.

If it is inline with the load velocity and you are getting good accuracy, loading up can only shorten case life and be hard on your rifle. be happy with your loads.

Loading until you see pressure signs means that you are on the edge of problems and under certain temperature conditions, you can get into trouble. Most of the time if your rifle is chambered correctly and loaded proper ammo that shouldn't create pressure problems you are at or near the SAMMI pressure limits of the designed cartridge.

I have rifles that are built specifically for SAMMI pressure and velocities without achieving pressure signs on the cases and heavy bolt lift.

Just My Opinion

J E CUSTOM

J E Custom speaks truth!

One should generally avoid exceeding maximum published loads. In fact, the customary advice is to work up to that load beginning with a suitable starting load. Chances are one will find a very accurate load on the way. Best to use that slightly less than max load and you, your brass, and your rifle will be happy campers.

 

[jasonco]

Huh? I'm confused, why are you suggesting that cratered primers are not an indication of over pressure? I don't mean to be argumentative, I'm just trying to understand where you're coming from.

Because it's likely a function and idiosyncrasy of rifle itself, Iv several that display cratered primers, but not over pressured. Now if the primer is horribly flat and the case has ejector swipes and a sticky extraction, we'd better stop immediately with that load and back off the charge, to safer level.

 

[Havard]

Nice group. What FPS are you getting with rl-16?

Also got a nice / similar group at 41.7gr. In fact, I almost stopped at 41.7 but was trying to get closer to max.

 

[MOOSE39465]

This is a case

Also got a nice / similar group at 41.7gr. In fact, I almost stopped at 41.7 but was trying to get closer to max.

I would take that any day!

 

[Ted Sierocinski]

Rifle-Remington 700 6.5 Creedmoor
Bullet-142 Grain Accubond long range
Power-H4350

Went to the range today and done some load development. I was pleased to see my rifle really liked the Accubond long range bullet. When I got to the max load on the Nosler website I examined the cases and was surprised I didn't see any pressure signs. My question is what now? Should I just start increasing to powder charge until I see ejector marks or stop at max? I posted a picture of a case so you could see for yourself.