A little stumped load development virgin brass vs once fired

[4thefunofit]

I've read that modern cartridges having less tapered walls, and AI cartridges don't show pressure signs as readily as older more tapered cartridges. So it seems prudent to not exceed published maximum loads, and not rely on typical pressure signs.

 

[Old Rooster]

In all my years of shooting/reloading I have learned that mistakes can be an investment if you learn something from them.
I have never had the pressure signs the OP had but it is a learning experience for me and hopefully I won't make that mistake of over loading.
Thats why we have this great forum,to learn from others investments and improve ourselves.

 

[milboltnut]

I knew a guy who was a recoil junkie, and went way over max with his Weatherbys, never had a problem. Not something I would do, even with the strongest actions.

 

[ripzip]

Ok, your load is 60.0 of Retumbo with 153 A-Tip, as stated this a 4.0 full grains over max load listed by Hodgdon for the 153 A-Tip. This is in dangerous territory to be 4 grains over any listed load. It doesn't matter what Berger has to say for their 153 in comparison to the 153 A-Tip. Different bullet construction, alloy materials, bearing surfaces, cannot be assumed to be equivalent load data. IMO back off the 153 A-Tip load within established published load data. We all try to gain "little bit" but 4.0 grains is not considered a "little bit". This is at least 7% over published load data and who knows what the actual pressure truly is.

I have always trusted powder load data more than bullet load data. Powder manufacturers are not trying to sell glitzy performance of their bullets. JMO

View attachment 343656

I agree with you totally. When I did the initial loading with the A-Tip's I only went as high at 56.5. When I got the Berger data and started shooting their 153's and starting off at Min of 57gr and not finding any pressure signs until 62gr where I stopped. So looking at this I figured that I would try to push the A-tips as the Bergers were similar bullets. I though I would take the A-tips up to where I would see pressure also. I did not do that before as the published data told me a Max of 56gr. Again no pressure signs until 62gr same as the Bergers. Figured that possibly Hornady was just being conservative, I was well under the Berger max, according to them. So I settled on a charge of 60gr that gave me good velocity ES and SD. Was using same load for both bullets with no pressure signs. I felt like I was being safe, like I said, until I started using the once fired brass.
This was a learning experience for me as I never reloaded anything even at max published data until I started loading for the 6.5 PRC. All other cartages I have been reloading, I just tried to find something accurate between the min and max load and leaving it at that. Never had I tried to reload until I found pressure signs. Of course when I started reloading I was reloading for an AR10 and AR15, then my bolt guns later on.
As I said I learned my lesson, glad that it was not the hard way.

 

[Muddyboots]

I agree with you totally. When I did the initial loading with the A-Tip's I only went as high at 56.5. When I got the Berger data and started shooting their 153's and starting off at Min of 57gr and not finding any pressure signs until 62gr where I stopped. So looking at this I figured that I would try to push the A-tips as the Bergers were similar bullets. I though I would take the A-tips up to where I would see pressure also. I did not do that before as the published data told me a Max of 56gr. Again no pressure signs until 62gr same as the Bergers. Figured that possibly Hornady was just being conservative, I was well under the Berger max, according to them. So I settled on a charge of 60gr that gave me good velocity ES and SD. Was using same load for both bullets with no pressure signs. I felt like I was being safe, like I said, until I started using the once fired brass.
This was a learning experience for me as I never reloaded anything even at max published data until I started loading for the 6.5 PRC. All other cartages I have been reloading, I just tried to find something accurate between the min and max load and leaving it at that. Never had I tried to reload until I found pressure signs. Of course when I started reloading I was reloading for an AR10 and AR15, then my bolt guns later on.
As I said I learned my lesson, glad that it was not the hard way.

We have ALL been there and done that at one time or another! So glad no apparent issues! I just posted up a thread on pressure and accumulative effects that @Carlos88 was able to provide the link to the article I was looking for. Its pretty good and talks about metal fatigue that I wanted to discuss with a friend not on LRH but could not find the article. The LRH brain trust, as always, seems to come through! I read this when it first came out and still rings true today. I think it is worth a read.

SMALL ARMS SAFETY EXAMINATION AND TEST PROCEDURES, Feature Articles- FirearmsID.com

Forensic Firearms Identification is a discipline of Forensic Science that has as a primary concern to identify fired ammunition components as having been fired from a specific firearm.

www.firearmsid.com

 

[lancetkenyon]

Intersting that not a single post has addressed the very well known issue of the 6.5PRC SAAMI chamber and 6.5PRC dies NOT sizing brass down enough, so that subsequent FL sizing, loading, and firings cause clickers and overpressure/sticky bolts, etc.

Besides the fact that 3125 in a 6.5PRC with a 153 is CRAZY velocity.

 

[Shane Lindsey]

But...If you break the brass...No die in the world is going to get it back to spec....Ask me how I know

 

[ripzip]

We have ALL been there and done that at one time or another! So glad no apparent issues! I just posted up a thread on pressure and accumulative effects that @Carlos88 was able to provide the link to the article I was looking for. Its pretty good and talks about metal fatigue that I wanted to discuss with a friend not on LRH but could not find the article. The LRH brain trust, as always, seems to come through! I read this when it first came out and still rings true today. I think it is worth a read.

SMALL ARMS SAFETY EXAMINATION AND TEST PROCEDURES, Feature Articles- FirearmsID.com

Forensic Firearms Identification is a discipline of Forensic Science that has as a primary concern to identify fired ammunition components as having been fired from a specific firearm.

www.firearmsid.com

Question then. As it sits right now my OCW is at 56.5 with the velocity of 2950. Should I re evaluate and start over for the OCW? As it is I had some of my brass that I threw out because the primer pockets were loose most likely form those 57gr and above charges. I really do not want to burn the barrel out, eat up brass and just in general cause unnecessary harm to my rifle.
Always ready to learn from others on this forum.

 

[waveslayer]

I haven't read all 6 pages of this but your brass has expanded and your reloading die may be oversizing the brass and changing neck tension etc. Measure all of it and go from there . Has your velocity changed with your new loads

 

[orkan]

Question then. As it sits right now my OCW is at 56.5 with the velocity of 2950. Should I re evaluate and start over for the OCW? As it is I had some of my brass that I threw out because the primer pockets were loose most likely form those 57gr and above charges. I really do not want to burn the barrel out, eat up brass and just in general cause unnecessary harm to my rifle.
Always ready to learn from others on this forum.

Start over. No way you can live at 2950 and get more than 3 firings from even the best brass. You're lucky to even get 1 firing at that velocity.





You should be able to achieve somewhere in the 2850fps range with that bullet in a 26" barrel. 2900 is achievable in a fast barrel, but even that will be right on the edge and you'll suffer consequences for that, all outlined in the above videos.