Mid load pressure signs

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cbh560

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Hey all,
First a little background. I am shooting and Rem 700 SPS Tactical in .223. I am reloading for it and am trying to figure out what my problem is.

The load:
-federal brass (3x fired) and FL sized
-CCI 400 primers
- 69gr Sierra Matchking
-23.9gr of H335
- COAL of 2.290" which is ~0.010" off the lands for this rifle

The problem:
According to the Sierra manual, a load of 23.9 gr of H335 for the 69's is right in the middle of the spectrum at approximately 2800fps. However, I am getting fairly flattened primers and cratering. Otherwise there are no signs of pressure. No hard extraction, no apparent case head seperation, no split necks, etc. The cratering I can understand, as I have often heard that Rem's have oversized firing pin holes. But what about the flattened primers? Do I have cause for concern or any suggestions to how I could fix the problem? I am looking to try making another load with Varget, maybe the problem will go away....

Thanks for any advice or help
 
Does your 700 have a loose firing pin/firing pin hole fit?
A flat primer may indicate high pressure. It might also indicate excess headspace.
Why not try the load in brand new brass?
 
Read on here that lots of people have good success with varget. I have run up to 26.5gr with varget and 69gr smk. There wasnt much for pressure signs even at 26.5 for me. I stopped loading for them because no matter what they shot like crap
 
tiriaq said:
Does your 700 have a loose firing pin/firing pin hole fit?
A flat primer may indicate high pressure. It might also indicate excess headspace.
Why not try the load in brand new brass?
Click to expand...

Its no sloppier than I would expect from factory tolerances. I hadn't though of the headspace issue. Are there other indicators of excess headspace that I may see?
 
FWIW, I have a Remington 700 factory hunting rifle in .30-06. I have found that FL resizing the brass often gives flattened primers when neck sizing does not with the same load. I attribute this to a slightly longer/sloppier chamber on factory Rem 700s. If the chamber is slightly long, then FL resizing it creates a bit of a headspace gap. It's not dangerous, but it is a bit of a gap. Upon firing, the brass expands and slams backward onto the primer (which has crept out a little at the moment of firing because of tiny headpsace gap). The result is an instant flattening of the primer, in a situation where the pressure is actually normal. I call this a false pressure sign (and there are other types of false pressure signs, as well).

I don't use factory loads, so I can't say whether the situation would hold true with factory ammo. However, if it didn't, and factory loads had normal looking primers, I would attribute it to the way that factories keep the primers in the case so tightly, often employing glues and seals, and using factory tight primer pockets. On the other hand, I have pulled many boxes of fired factory .30-06 brass out of the garbage at the range, and I have been surprised to see how many fired factory cases have flattened, or moderately flattened, primers. This suggests to me that even factory loads can give false positive pressure signs in some rifles, likely because of sloppy factory chambers.

This is why I would recommend that you try neck sizing or partial FL sizing next time, if you can, when working up a load. I NEVER use FL sized brass for working up loads in factory chambers for this reason. (The situation is different on my competition rifles with custom tight chambers.)
 
I used to run CCI400 primers in my 223 but I found they were very soft so I switched to CCI BR-4's and I have much more normal pressure signs. I would drop 3/4 to half a grain of powder and switch to another primer and work back up, I am betting you are having the EXACT same issue I had.
 
Becoming an older thread now, but I just had a thought. I am using Federal brass and FL resizing every time (I currently don't have a neck sizing die). On the third and fourth reloadings of the cases I have noticed that it takes considerably less effort to seat primers. I am assuming that the primer pockets have opened up a bit since the brass was new. Would this looser fitment of the primers cause them to move out of the pocket and squeeze against the bolt face, thus flattening them? I have read in several places that Federal brass is sometimes not as hard as it should be in the case head..... any thoughts?
 
Good thinking, also if you are starting to see loose primer pockets after 3 loads, that could also be an indicator that you are running at peak pressures. Have you measured new brass and compared them to your fire formed brass to see how tight/loose your chamber is?
 
Too much resizing may also cause flat primers. Before firing these case again, use a bent wire to check case wall uniformity in the head area (up to about 0.200"). If you feel a "bump", discard the cases.
 
loose pockets and flat primers indicate high pressure. Not necessarily excessive, but high. You are loading at the max load for the rifle in the lab. That load could be too hot by a half grain for your rifle.

Drop a half grain and see if problems go away.
 
If your primers are easier to seat, push in, after only 3 or 4 firings, your load is much too heavy.
Primers loosening are a sure sign of too heavy a load.
 
Baribal - I have checked the case walls with a bent paperclip and they seem fine, no apparent case head seperation

Ganderite - I have loaded up some new rounds with less powder for further testing. I dropped the powder by .4gr

H4831 - I thought they may have been a little high, but wasn't seeing any other pressure signs so I though maybe the heads were just "soft". Are these brass still safe to continue loading with lower powder charges, or should they tossed in the garbage and start with new brass? I have been looking for an excuse to buy some Lapua brass......
 
Your load is max load from the Hornady manual but shouldn't be a problem, did you work up to that load starting with lighter loads? Try seating your bullets a bit deeper. With no bullet jump to the rifling sometimes pressure can spike.

I have an SPS tactical in .223. I do get more firing pin cratering than with most other rifles I shoot, even with moderate loads. I load 23 gr of Varget (a moderate load) to 2.205" overall length and I neck size with a Lee collet die. I just keep re-using my cases without any problems and if my 5 shot groups are over 1" I did something wrong. Max load is not necessarily the best load.
 
762shooter said:
Your load is max load from the Hornady manual but shouldn't be a problem, did you work up to that load starting with lighter loads? Try seating your bullets a bit deeper. With no bullet jump to the rifling sometimes pressure can spike.

I have an SPS tactical in .223. I do get more firing pin cratering than with most other rifles I shoot, even with moderate loads. I load 23 gr of Varget (a moderate load) to 2.830" and I neck size with a Lee collet die. I just keep re-using my cases without any problems and if my 5 shot groups are over 1" I did something wrong. Max load is not necessarily the best load.
Click to expand...

I was using the Sierra Manual when I worked up the load, and the 23.9gr of H335 is about midway in the spectrum. I figured that this may have been the most accurate since I am shooting Sierra bullets, but apparently this was an incorrect assumption. I wasn't going for the max load, just happened to find an accuarcy node in a ladder test based on Sierra's information, which has a max load considerably higher. I am going to back off the load and possibly seat deeper to try to reduce pressure.

However, now that the "damage" is done to the brass, am I going to continue to see strange signs even though the pressure is down? Do I need to buy new brass and start over?
 
First of all , I don't believe there is such a thing as "false pressure signs". If the signs are there to read then there is excess presure and steps should be taken to reduce it.

Flattened primers show you are at the top end of the safety envelope, primers with firing pin craters have passed that. I know some people ignore the warnings and get away with it but I've seen holes in firing range walls from gun parts where they didn't.

One reason that I haven't seen mentioned for excess pressure in loads that ordinarily would be fine is that the case is to long and when chambered the rifling pinches the case mouth creating in essence a barrel restrictiion for the bullet to pass through. Even tho you are full length sizing the neck can still be streched enough that the case is over length.

I once had a .270 rifle brought to me that was showing pressure with a load that was little more than suggested starting point. The cases were 3rd time full-length sized reloads. When we looked at his cases closely we ccould see definite rifling imprints on the outside mouth. We run his brass thru my trimmer,loaded them up and his pressure signs disapeared, infact he was able to increase the powder charge by 3 grns and still was okay.

You might argue that people shoot thousands of crimped loads with no problem and you would be right, however those loads are with brass that is at spec. or less and the brass has room to open in the chamber-freebore area. In the scenario I wrote about, the brass has no room to open. For a very short distance you are essentially forcing a bullet thru a hole that can be as much as 2 calibers too small.
 
fingers284 said:
First of all , I don't believe there is such a thing as "false pressure signs". If the signs are there to read then there is excess presure and steps should be taken to reduce it.

Flattened primers show you are at the top end of the safety envelope, primers with firing pin craters have passed that. I know some people ignore the warnings and get away with it but I've seen holes in firing range walls from gun parts where they didn't.

One reason that I haven't seen mentioned for excess pressure in loads that ordinarily would be fine is that the case is to long and when chambered the rifling pinches the case mouth creating in essence a barrel restrictiion for the bullet to pass through. Even tho you are full length sizing the neck can still be streched enough that the case is over length.

I once had a .270 rifle brought to me that was showing pressure with a load that was little more than suggested starting point. The cases were 3rd time full-length sized reloads. When we looked at his cases closely we ccould see definite rifling imprints on the outside mouth. We run his brass thru my trimmer,loaded them up and his pressure signs disapeared, infact he was able to increase the powder charge by 3 grns and still was okay.

You might argue that people shoot thousands of crimped loads with no problem and you would be right, however those loads are with brass that is at spec. or less and the brass has room to open in the chamber-freebore area. In the scenario I wrote about, the brass has no room to open. For a very short distance you are essentially forcing a bullet thru a hole that can be as much as 2 calibers too small.
Click to expand...

You bring up an excellent point. I have already checked into this and my brass are still within spec. The cratered primers I tend to ignore, as this rifle gave me cratered primers at beginning loads. And I have read in several different places that this is common in Remingtons due to a slightly oversized firing pin hole. The flattened primers is when I started to pay a little more attention.
 
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