Reloading- What pressure signs do you stop at?

[hankle]

Dear safety Steve, we ask politely that you sit this one out. Or, just limit your input to photographic evidence...

What pressure signs do you stop at?

This question is for the guys who want the most out of velocity. I have rifles that I don't push and just shoot for accuracy even if it is well below the max. I have a couple that I like to push to the max. So, where do you maverick's draw the line with pressure signs. Is it when primers begin to flatten, completely flatten, crater primers, hard bolt lift, ejector marks, swipe, etc.. I know there are false pressure signs, please include experience with that.

Rules for answering:
Rule number one: Safety First
Rule number two: Lets hear real world experience, not ethics or safety Steve ranting about not testing boundaries.
Rule number three: Let the dragon breath!

 

[ATH]

I monitor bolt lift, primer flattening, and ejector marks. Pressure is pressure so these things will move in concert. In my experience by the time you get heavy bolt lift you are already too far. I stop at a mild ejector mark and moderate primer flattening -- if you see that you are beyond standard pressures already.

 

[old_heli_logger]

Federal primers have softer cups than most other brands, so flattening is allowed for me when using that brand. Any bolt face marks at all in the brass or any heavy bolt lift and I back off a half grain or so.
Good luck and be careful

 

[hankle]

Federal primers have softer cups than most other brands, so flattening is allowed for me when using that brand. Any bolt face marks at all in the brass or any heavy bolt lift and I back off a half grain or so.
Good luck and be careful

A helo logger is just the type of man I trust advice from! Thank you...

 

[338 dude]

Dear safety Steve, we ask politely that you sit this one out. Or, just limit your input to photographic evidence...

What pressure signs do you stop at?

This question is for the guys who want the most out of velocity. I have rifles that I don't push and just shoot for accuracy even if it is well below the max. I have a couple that I like to push to the max. So, where do you maverick's draw the line with pressure signs. Is it when primers begin to flatten, completely flatten, crater primers, hard bolt lift, ejector marks, swipe, etc.. I know there are false pressure signs, please include experience with that.

Rules for answering:
Rule number one: Safety First
Rule number two: Lets hear real world experience, not ethics or safety Steve ranting about not testing boundaries.
Rule number three: Let the dragon breath!

I stopped exactly where you are speaking of heavy bolt lift, primer, cratering, flatten, primers, etc. etc.

 

[Stammster2]

I give a lot of weight to velocity as measured by my Magnetospeed and how it compares to QL predictions of pressure for that particular powder. Calibration of Ba is nice for comparing charge weight to velocity, but not necessary to get a usable pressure vs velocity prediction.

Since I shoot mostly flat bolt face guns (Kimber and M70 Pre-64), you don't get noticeable ejector marks / swipes on the case heads like you get with M700 actions. Therefore I rely on bolt lift "feel" — but in my experience even that doesn't usually show up unless I'm 5-7kpsi over max calculated from QL.

I give very little weight to flattened primers - but still check.

 

[DoneNOut]

If I can't get my thumbnail to catch the edge of the primer because it is smeared to the edges of the primer pocket...I take hard notice. Typically backing down from primer smear puts me in the safe zone. Stiff bolt on properly sized brass/properly bumped shoulder is a hard stop for me. Reduce 1.5gr.

Chrono lets me know sometimes too. Like a .5gr increase of powder that only gives similar or very close velocities to the lessor charged powder weights.

 

[Sockeye66]

Answers to this thread should be copied and posted in reloading manuals.

 

[Hugnot]

I don't have any piezoelectric sensor equipment & I don't like to destroy valuable brass so I rely on published load data & cautiously work my way up to max load data. I have found most max load data produce excessive pressures as indicated by hard bolt lifts & expanded primer pockets. High quality rifle brass having adequately work hardened case heads & especially small primer pockets enable higher pressures to be applied - an example being Lapua 6.5X47 brass.

 

[willfrye027]

Usually will drop .5-1gr below ejector mark assuming no heavy bolt lift. Then will reload a couple cases over and over and make sure they last at least 4-5 firings.

However I did this with an absolute hammer load in my 30-06 that was sizzling fast but seemed ok by the above parameters. Using Varget so very temp stable.

Hunted in the snow and got pretty wet. Fired a round just to see what would happen…blew the primer. Not sure if the outcome would have been different with even factory loads but it does raise some concern on the validity of my methods.

 

[slikmrc]

I use a micrometer that measures to the .0001 to measure the case above the extractor groove. File flats on a new case rim so I can mic the case from the base end. First load is mild to form the brass a bit then work up in 1 to .5 grains until I see brass start to expand. I then back down to the last load that didn't have any expansion and fire a couple more times to make sure it's good to go. On some hunting loads I'll use .0002 expansion as the cut off. My thinking is I should get 4 to 5 loadings before the brass is junked. If brass lot is changed I do another work up of that brass. This process has served me well. Learned this from a book Bob Hagel wrote years ago.

 

[cajun]

Usually will drop .5-1gr below ejector mark assuming no heavy bolt lift. Then will reload a couple cases over and over and make sure they last at least 4-5 firings.

However I did this with an absolute hammer load in my 30-06 that was sizzling fast but seemed ok by the above parameters. Using Varget so very temp stable.

Hunted in the snow and got pretty wet. Fired a round just to see what would happen…blew the primer. Not sure if the outcome would have been different with even factory loads but it does raise some concern on the validity of my methods.

Thats the problem with pushing the envelope. Something changes and now that load that was over max by a little bit is suddenly unsafe. That is why no saami max pressure is over 65k. It gives you some wiggle room. Reading primers is unreliable. By the time you get sticky bolt lift your likely way over max. Bolt design and brass hardness can affect ejector marks. People dont like to hear it but if you want to be safe stay within the realm of published velocities. I can load my 6.5 creedmoor with R 26 and a 140 to 3050 with zero pressure signs.Ql has the pressure on that load at 66K. The max published velocity in the Hornady manual with that combo is 2850 in a 24" so maybe 2900 in my 26". I can live with that.

 

[back40sniper]

Combination of signs, when I used just one brand of primers could keep an eye on primer flattening out. Bolt lift and marks on brass, but the one thing I have found for sure is as BFD mentioned, once you stop getting same level of velocity increase for powder increments you are usually "there".

 

[dblman]

Dear safety Steve, we ask politely that you sit this one out. Or, just limit your input to photographic evidence...

What pressure signs do you stop at?

This question is for the guys who want the most out of velocity. I have rifles that I don't push and just shoot for accuracy even if it is well below the max. I have a couple that I like to push to the max. So, where do you maverick's draw the line with pressure signs. Is it when primers begin to flatten, completely flatten, crater primers, hard bolt lift, ejector marks, swipe, etc.. I know there are false pressure signs, please include experience with that.

Rules for answering:
Rule number one: Safety First
Rule number two: Lets hear real world experience, not ethics or safety Steve ranting about not testing boundaries.
Rule number three: Let the dragon breath!

Crony is best, safest way to develop loads that there is I believe, watch load increase increments, stop when you hit that unusual increase, or maybe even decrease.
Works great as velocity increases as good indications of pressures.
mmman20