Simple one for you pros...

[26Reload]

shot the 65284norma last weekend at the coast...NEW LAPUA BRASS..215 PRIMER..4831sc(varied charges..no chrony)
This box shows to the left...
7@120gr hornady..all 49gr...
top two rows 140gr berger...all 49gr...
Third row from top..center 5...52, 52.5, 53, 53.5, 54gr
To my eyes the 53.5 and 54 have the least amount of flattened primer...
To my eyes the primers look awfully flattened for lower pressure rounds to work brass to fit chamber...NO HEAVY BOLT LIFT ON ANY FIRING...
Whatcha all think...
I have sent picture to my gunsmith an he will recheck everything when he gets back in town....

 

[gohring3006]

Primers are not a good indicator for pressure.
Especially in new brass.

When you have sloppy new brass, and you fire, the firing pin pushes the sloppy case forward, the pressure can shove the primer out of the pocket, then the case head comes slamming back against the boltface, and that partially ejected primer gets flattened in the process.
I watch for ejector marks with a proven chronograph.
If your velocity is higher than book max, and you have a ejector swipe, then you are over pressure.
If I'm able to load at the range, I just use one piece of brass over and over once I find a good load, and I'll fire it several times to see if my primer pocket open up prematurely. Like 6-7 firings or less.

 

[26Reload]

Yep...sloppy case is understood...and primer slamming is understood...and no chrony...thought the other guy would have his new one in rig.....wrong...
No ejector marks...
No resistance at all with bolt lift...
Haven't ever shot lapua brass before...most guys are running 3 shot before having to resize....this is first firing....

 

[gohring3006]

I would go to the third firing, and get the die setup for .002" setback, then get serious. I would personally probably just go with the 53 grain load to fireform the next firing.

 

[cdherman]

gohring3006 explanation is spot on in my experiences too. Really hard to use primers as a valid test for pressure, UNLESS, you know from experience what they are usually looking like, and then, with a new powder or charge, all other variables (especially case) the same, they are flattened. Then I would worry....

With a new barrel, you should be breaking in with some cheap bullets and powder you don't care for anyhow. Bartlein says clean after ever shot for first 5, then every other or so. Its painful. And they rec using patches. No brush, not even nylon. So I basically get my first 50 fired brass during the breakin process. Then I start in earnest.

Alas, brass will sometimes not grow to your chamber in the first firing. You can spot those when the primer is protruding a tad. Othertimes, you will only realize your brass did not all stretch the same if you use a good base to shoulder tool (Hornady etc) and realize that your fired brass is not all the same. Pros say you cannot assume its all the same till three firings. UNTIL its all the same length, the issue of a primer popping out, then getting flattened as the case head stretches remains...

I have this old M94 6.5x55 swede that has generous headspace. And a rough chamber I think. But it also shoots bug holes on occasion. It flattened all the primers for the first 2 firings of my Lapua brass. I was totally spooked (18 years ago now), and it took me years to understand what was happening.

Ah the confusion....

 

[26Reload]

This barrel is a rechamber...had it put on my wife's ruger compact but it made the rifle too heavy for her...so I put her compact back together and found a Remington action for the 24.5" while barrel..
Not breaking anything in other than new chamber....new stock...fluted bolt...new scope......new trigger... And new cartridge....
It will be fun....

 

[cdherman]

This barrel is a rechamber...had it put on my wife's ruger compact but it made the rifle too heavy for her...so I put her compact back together and found a Remington action for the 24.5" while barrel..
Not breaking anything in other than new chamber....new stock...fluted bolt...new scope......new trigger... And new cartridge....
It will be fun....

You still need to break in a rechamber. The critical throat area is where there will be rough areas from the new reaming. That leads to copper being scraped away and vaporized, then laid down in the barrel. Too many layers and bad ju-ju. Last part from me. First 3 sentences from lots of reading. I suspect there is no one alive that has proper scientific evidence about barrel break in......

 

[Greyfox]

Federal 215 primers can generate higher pressures/velocity by as much as 30-50 FPS. I find that 53/210M is my max load(and my best accuracy/ES) in my three 6.5x284 rifles using a 140 but this can certainly vary with different chambers and seating depths. I would try a 1x fired case first with your current load; then a load with a 210 primer to compare the appearance of the primers.

 

[just country]

morning, listen to the greyfox!! all members have great info.
gbot tum

 

[26Reload]

I understand about pressures 215 vs 210...in max loads but as far as I have been able to follow along on several threads about 65284 49gr 4831sc should be nowhere close to a max with 120 or 140gr bullets....the five shots with gr increase from 52-54 showed no ejector marks on brass..and 53.5 & 54 showed the least growth in primers circumference....no heavy bolt lift....

 

[Shane Lindsey]

FWIW I have read and "believe" to have witnessed with some of my own loads that if they are too low they can almost have the same effect on brass as a higher end load. Meaning the pressure is not high enough to quickly expand the case and it allows for more movement of the brass rearward in the chamber.

Not a scientist and definitely not studied it but you know about internet information.

 

[Greyfox]

FWIW I have read and "believe" to have witnessed with some of my own loads that if they are too low they can almost have the same effect on brass as a higher end load. Meaning the pressure is not high enough to quickly expand the case and it allows for more movement of the brass rearward in the chamber.

Not a scientist and definitely not studied it but you know about internet information.

I have also seen this but I doubt the OP's pressures are too low with the load he describes. The OP is using new brass. I have also experienced flattened primers with new brass which can have as much as .006" of headspace. This can sometimes effect the primer shape on the first firing. If the primers are still flattened with once fired brass, I would strongly suspect that pressures are high. While this may not always be the case when primers are flattened, H4831/sc is a fast burner compared to Retumbo and R26. The pressure wall tends to show up very close to 53g in several 6.5x284 rifles I have owned. While loads with H4831sc have proven to be exceptionally accurate, velocity for a given barrel length will generally run 50-100FPS lower, and pressures will be higher compared to a slower burner like Retumbo. An added benefit of Retumbo is that many have experienced longer barrel life due to the slower/cooler burn that concentrated less heat in the chamber throat. These two loads, just shy of pressure signs, generate about the same pressure in my Savage LRH.

 

[Wachsmann]

My rifle would only get to 51.5grns of 4831SC . this actually produced the slightest ejection mark. If I loaded 52 or 51.7grns I had ejection swipes. This was all with 140 bergers. Shot great but not the fastest. Only about 2850fps. Hybrid 100V was a little faster at 2880 but 49 grns. It was not temp stable so in the summer I had to switch out to a different load.

 

[26Reload]

Oh believe me when I say I have been reading all the 65284 I can and watching all the threads pop up...
Can't understand all the 7stw brotherhood and how 65284 hasn't generated one yet.......:rolleyes: