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Old 10-02-2012, 12:56 PM
fish_e_o fish_e_o is offline
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Default overpressure loads

i have a rem 700 in 300rum and it likes to shoot very very hot loads of retumbo.

the primer looks.. ok.. you can tell it's not a reduced load lets just say that.

the brass is ever so slightly having the impression of the bolt face left in it.

but i've never used federal brass before and people say it's soft.

i've shot about 5 of these and they shoot amazing and very very flat. i would love to start using it as a hunting load. the loads were made on a warm day so it shouldn't get higher.

opinions??

will post pictures tonight.
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Old 10-02-2012, 01:02 PM
fish_e_o fish_e_o is offline
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also it's .5 gr less than a max load.
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Old 10-02-2012, 05:51 PM
fish_e_o fish_e_o is offline
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i know it's hard to see but look at the "mag" part
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Old 10-02-2012, 06:04 PM
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A better way to tell is to mic the case just above the rim, both before and after a shot. This should be done with once fired brass in that rifle that has not been subjected to any hint of pressure. If the case is expanding then it is over pressure for that gun.
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Old 10-02-2012, 06:05 PM
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Overt pressure signs are signs you are over pressure, not by a little but usually by a lot.
Primer flatness or not, your getting ejector marks in your brass, which is'nt a good thing. Make of brass be damned, your over pressure with the given combination.
I'd wager you are at least 15% over the maximum design pressures for this cartridge.

The funny thing is that nasty issue called cumulative metal fatigue. If you really want to continue down a possible road to ruin..keep at er!
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  #6  
Old 10-02-2012, 06:10 PM
bulletman bulletman is offline
 
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Default loads

You would be wise to back this load off at least a couple of grains for sure.
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Old 10-02-2012, 06:26 PM
Pathfinder76 Pathfinder76 is offline
 
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Quote:
Originally Posted by Dick284 View Post
The funny thing is that nasty issue called cumulative metal fatigue. If you really want to continue down a possible road to ruin..keep at er!
I'm curious if anyone has seen the results of cumulative metal fatigue? I hear it batted around enough that there must be some examples of it somewhere.

I have a friend that has probably close to 10,000 rounds on one Remington 700 action (more than one barrel) and probably one half to one third of them were ridiculously hot and he seems to be carrying on no problemo.
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Old 10-02-2012, 06:43 PM
fish_e_o fish_e_o is offline
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Quote:
Originally Posted by Dick284 View Post
Overt pressure signs are signs you are over pressure, not by a little but usually by a lot.
Primer flatness or not, your getting ejector marks in your brass, which is'nt a good thing. Make of brass be damned, your over pressure with the given combination.
I'd wager you are at least 15% over the maximum design pressures for this cartridge.
holy crap i was wondering why it was so high pressure so i looked in my book again made sure i had the right powder out everything. sure enough i did.

hornady says 104.8 gr max load. i shot up to 104.2 before i stopped and i found a load i like at 101.5. even at 101.5 it was leaving the ring. so i picked up my sierra book (because i don't trust hornady reloading) and it says max load 99.9gr for retumbo with 165 gr bullets i think i started my ladder test at 94!!!

time to restart!!
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Old 10-02-2012, 07:44 PM
elkhunter11 elkhunter11 is offline
 
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I would be dropping the powder charge until the brass extrusion disappears completely, then at least another grain, possibly two. One accident due to a case rupturing or an action finally fatiguing to the point of failure is one too many for me.
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Old 10-02-2012, 08:31 PM
Bolete Bolete is offline
 
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Quote:
Originally Posted by fish_e_o View Post
holy crap i was wondering why it was so high pressure so i looked in my book again made sure i had the right powder out everything. sure enough i did.

hornady says 104.8 gr max load. i shot up to 104.2 before i stopped and i found a load i like at 101.5. even at 101.5 it was leaving the ring. so i picked up my sierra book (because i don't trust hornady reloading) and it says max load 99.9gr for retumbo with 165 gr bullets i think i started my ladder test at 94!!!

time to restart!!
What bullets are you shooting? Not all bullets of the same weight produce the same pressures with identical powder charges.
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Old 10-02-2012, 09:22 PM
fish_e_o fish_e_o is offline
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What bullets are you shooting? Not all bullets of the same weight produce the same pressures with identical powder charges.
well i was shooting hornady interbonds but i think the sierra book is more in line 99% of the time with everything
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Old 10-03-2012, 06:30 AM
eric2381 eric2381 is offline
 
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I agree that you are high pressure.

Me, I'd set the federal brass aside and try some Remington brass in that RUM.

What kind of brass is used in the hornady manual?
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Old 10-03-2012, 08:41 PM
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Quote:
Originally Posted by fish_e_o View Post
i have a rem 700 in 300rum and it likes to shoot very very hot loads of retumbo.

the primer looks.. ok.. you can tell it's not a reduced load lets just say that.

the brass is ever so slightly having the impression of the bolt face left in it.

but i've never used federal brass before and people say it's soft.

i've shot about 5 of these and they shoot amazing and very very flat. i would love to start using it as a hunting load. the loads were made on a warm day so it shouldn't get higher.

opinions??

will post pictures tonight.
For hunting loads I stay under well under max both for safety and for the reason that I want them to function in my rifle with 100 percent reliability. I also only use full length resized brass for hunting and after three firings I no longer use them as hunting rounds. Perhaps I am a bit picky but I've never had an issue in the field (knock on wood), and I don't think the game has noticed the difference. Safe and happy reloading to you. http://outdoorsmenforum.ca/images/smilies/smile.gif
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Old 10-04-2012, 08:47 AM
Leeper Leeper is offline
 
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Bolt face impressions on brass can be deceiving. Such marks can be a sign of excessive pressure or they may be signs of head clearance or of machining flaws on the bolt.
Tell you what; if you take a piece of brass, load it ten times with the load of choice and the primer pocket stays tight, you are probably fine. If after a few firings, the primer pocket gets loose, you are too hot regardless of what the book says.
I think the cumulative fatigue might show up if an action is heavily stressed for long enough but I'm quite sure this is more likely to show up with plain carbon steels (like a Mauser) than on a chromoly action. In addition, I think you could load a 223, for instance, to the point that the primer pockets were expanding and you still would not be generating enough bolt thrust to cause any problems with the bolt lugs. The gas cutting of the bolt face could be a problem though Increase the diameter of that case to that of the UltraMag though and it would be different story. Leeper
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Old 10-04-2012, 09:04 AM
elkhunter11 elkhunter11 is offline
 
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Quote:
Tell you what; if you take a piece of brass, load it ten times with the load of choice and the primer pocket stays tight, you are probably fine. If after a few firings, the primer pocket gets loose, you are too hot regardless of what the book says.
+1 I rely on primer pocket tension, (which is directly related to case expansion around the primer) more than anything else, when checking for pressure signs.
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Old 10-04-2012, 09:25 AM
fish_e_o fish_e_o is offline
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Quote:
Originally Posted by Leeper View Post
The gas cutting of the bolt face could be a problem though Increase the diameter of that case to that of the UltraMag though and it would be different story. Leeper
no gas cutting or case expansion. there are no primer gas marks on the bolt and the primer corners have a nice roundness to them. i haven't fired enough loads to check for primer tension but of the twice loaded there is no difference.
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  #17  
Old 10-04-2012, 11:22 AM
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Case or chamber with a bit of oil of some form, left on or in it, could cause breech thrust mark also.
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  #18  
Old 10-04-2012, 01:08 PM
fish_e_o fish_e_o is offline
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Originally Posted by 32-40win View Post
Case or chamber with a bit of oil of some form, left on or in it, could cause breech thrust mark also.
errr... now that you say it i wipe down all my loads but the last time i cleaned the rifle i don't think i cleaned the oil out of the chamber...
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