I went to the range today to do some load work on my dta. I'm still really green to this reloading so help me out. It really loved 42.5gr of h4350 with 140gr vld oal is 2.815". Is this too hot?
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Too hot for the 6.5cm?
- Thread starter 565fitter
- Start date
Looking at the primers it looks good to go. Great group @ 42.5. As long as the bolt opens easily looks like you are good to go.
QuickLOAD numbers (ran for a 26" inch barrel)
2,786 FPS
99.2% Propellant Burn
58,200 PSI (max is 60,000)
You may have a little left in the tank, but that is good if the groups are what you want.
2,786 FPS
99.2% Propellant Burn
58,200 PSI (max is 60,000)
You may have a little left in the tank, but that is good if the groups are what you want.
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QuickLOAD
quickload quicktarget software
QuickLOAD Review & User's Guide
Internal Ballistics Calculator. I use the heck out of it for load development and confirmation. Can't say that it is 100% accurate / 100% of the time, but with good data in, I have gotten velocities that are within 5 fps of what my chrono was reading on the actual rounds when fired.
I changed the numbers in the original to factor in a 26" barrel.
quickload quicktarget software
QuickLOAD Review & User's Guide
Internal Ballistics Calculator. I use the heck out of it for load development and confirmation. Can't say that it is 100% accurate / 100% of the time, but with good data in, I have gotten velocities that are within 5 fps of what my chrono was reading on the actual rounds when fired.
I changed the numbers in the original to factor in a 26" barrel.
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Pressure signs look great. The problem is going to be the poor brass quality. I loved that load too, but it's going to be a roll of the dice whether you get past 2-3 loadings before your primer pockets start loosening. I did not. If you research it a bit, you will find many other that did not as well.
Good Luck - I love the CM but my experience with the primer pockets will keep me from ever going back to that caliber. I wish you better luck than I.
Good Luck - I love the CM but my experience with the primer pockets will keep me from ever going back to that caliber. I wish you better luck than I.
Forget "reading primers" and "bolt lift" to determine pressure.
Aside from actively measuring pressure with a piezo-electric transducer, the gold standard is brass flow.
Learn to inspect for ejector marks on your case head. Serious overpressure will literally cause brass to flow into the ejector hole of your bolt face, creating a circular "button" on the casehead. Lesser (but still intolerable) overpressure might only leave a a circular mark you can only see in the right light with the case oriented just right.
Again, learn to see this. Once you know what you're looking for and at, you'll never lose brass to loose primers provided you shoot ammo that simply DOES NOT leave any ejector mark.
Any brass flow whatsoever means you are yielding the brass, which means you're in excess of what the brass is capable of.
Aside from actively measuring pressure with a piezo-electric transducer, the gold standard is brass flow.
Learn to inspect for ejector marks on your case head. Serious overpressure will literally cause brass to flow into the ejector hole of your bolt face, creating a circular "button" on the casehead. Lesser (but still intolerable) overpressure might only leave a a circular mark you can only see in the right light with the case oriented just right.
Again, learn to see this. Once you know what you're looking for and at, you'll never lose brass to loose primers provided you shoot ammo that simply DOES NOT leave any ejector mark.
Any brass flow whatsoever means you are yielding the brass, which means you're in excess of what the brass is capable of.
So an ejector smiley on a case head, in the absence of any primer flattening, means it's over pressure?
Aren't there other things that can attribute to ejector marks. A bit of Rem oil in the chamber, or maybe some case lube inadvertently not removed from a few cases?
I'm relatively new to precision hand loading as well so I'm not trying to be a smart ass. But most of what I've read about working up loads and watching pressure includes, in part, inspecting primers.
"Forget 'reading primers' and 'bolt lift'......."
For guys that are trying to learn, and learn the right way, it's difficult sometimes to decipher some contradictory info from whom we may regard 'the experts'.
I will soon be loading the 6.5cm as well.....but in a recent load work up for my 300wsm, I had some good looking primers in brass with ejector marks that were loaded well below max yet, and lube was suggested as a suspect. Shouldn't we be looking at the big picture and not ignoring what has seemed to me from reading and listening to be some signs of over pressure?
Aren't there other things that can attribute to ejector marks. A bit of Rem oil in the chamber, or maybe some case lube inadvertently not removed from a few cases?
I'm relatively new to precision hand loading as well so I'm not trying to be a smart ass. But most of what I've read about working up loads and watching pressure includes, in part, inspecting primers.
"Forget 'reading primers' and 'bolt lift'......."
For guys that are trying to learn, and learn the right way, it's difficult sometimes to decipher some contradictory info from whom we may regard 'the experts'.
I will soon be loading the 6.5cm as well.....but in a recent load work up for my 300wsm, I had some good looking primers in brass with ejector marks that were loaded well below max yet, and lube was suggested as a suspect. Shouldn't we be looking at the big picture and not ignoring what has seemed to me from reading and listening to be some signs of over pressure?
my cm loads will leave very very faint ejector marks in the case head. its soemthing i am will ing to accept. i know my load is at the edge but the performance out weighs the brass life for me. on a side note i have had very light loads leave ejector marks in brass just simply due to soft brass and possibly a slap happy ejector spring.
OK cool. 42.5 it is! Nice. Hoping I get some similar. Rifle should be here today. Brass should too. Gotta exchange the dies I ordered though. Ordered match Hornady dies and I'm just not gonna fool with bushings. Previous owner says regular dies gave him 0.3-0.5moa results. Why make it more complicated. Found some h4350 yesterday too.
IMHO, look at ALL of the signs for pressure!
Rifles & ammo have way to many variables going on to only look at one single thing as being the gospel.
I have seen a number of rifles blown up and people hurt chasing max loads, because they were ignoring a single pressure sign due to the other signs being OK.
If you are going "north of the border" on recommended load data, then IMHO you had better take whatever signs you can get, and act accordingly.
Rifles & ammo have way to many variables going on to only look at one single thing as being the gospel.
I have seen a number of rifles blown up and people hurt chasing max loads, because they were ignoring a single pressure sign due to the other signs being OK.
If you are going "north of the border" on recommended load data, then IMHO you had better take whatever signs you can get, and act accordingly.
Excellent point on brass/chamber lubrication causing ejector marks! You are thinking!
Absolutely oily or wet brass/chamber shows ejector marks sooner. My gold standard comment refers to dry and clean chamber and brass.
An experienced loader can do this - see the ejector marks, understand the variables, and willingly trade off brass life for performance.
Still the fact remains that ejector marks are caused by brass being stressed beyond its yield point, and literally flowing into the ejector hole.
I've been up in this territory before and walked the razors edge. Personally I feel its bad practice. These days I don't tolerate ANY ejector mark whatsoever if ammo and chamber are clean and dry.
If there is a performance bogey I MUST achieve, I'll choose a bigger cartridge rather than run a smaller one beyond its (practical) limit.
Yeah its not something I recommmed to anyone. Be safe and do what works for you. I've been through a couple barrels with my load and ran it hard it summer heat. Nothing more then light marks I have. But at 42.9 my
rifle does this at 705yds. Lol
rifle does this at 705yds. Lol
I'm up to 8 loadings with over 43 grains of 4350 and 139 scenars with hornady brass. No problems with primer pockets.
Exactly what I mean by "Roll of the Dice". I know of a handful of local shooters that never came close to that, including me. I was shooting 42.6 grains with no pressure signs at all other than the pockets going to crap after 2-3 loadings. I have read where many have successfully loaded that load where others like me just had poor luck.
Quick question for the dummy aka me....
How do you know when the primer pockets have gone bad? Is it as simple as the primers just not seating?
How do you know when the primer pockets have gone bad? Is it as simple as the primers just not seating?
When you seat the primers and the "Resistance " you get is minimal or in worst case scenarios ... Primers falling out of the pocket. This has to do with the primer cup getting weaker and weaker by each firing and ultimately results in gasses escaping from the pocket itself .... Not a good thing
Factory Hornady 140's show ejector swipes in my rifle because it jams them into the lands. My reloads that duplicate factory ammo velocity are 42.6 grains H4350, which also shows ejector swipes. I agree this is a sign that you are hitting pressure, but one lot of 50 rounds I've been shooting at this level has 6-8 loadings on it and I've only lost a few cases due to loose primer pockets. There is always a tradeoff between brass life and performance.
General question - not trying to steer this off the OP's original question, but about how many piece of brass do you guys have or cycle?
I will have 300 after I get done shooting all the factory ammo I have.
I will have 300 after I get done shooting all the factory ammo I have.
I load 100 at a time and keep 20 aside for load development should I want to try a new powder
Or bullet.
I get 10-12 reloads per case with the Hornady brass. When pockets get too loose I replace the case.
My load:
42.9 grns of H4350
CCI BR2 primers
139 scenar .015" off the lands
2855 fps with single digit ES
I size the brass with a Whidden FL sizing die with .289 nitride bushing
Trimmed to length after each firing
Annealed every 3 firings
Rifle:
SAC 6.5 CM
26" Bartlein barrel
Manners T6A
Or bullet.
I get 10-12 reloads per case with the Hornady brass. When pockets get too loose I replace the case.
My load:
42.9 grns of H4350
CCI BR2 primers
139 scenar .015" off the lands
2855 fps with single digit ES
I size the brass with a Whidden FL sizing die with .289 nitride bushing
Trimmed to length after each firing
Annealed every 3 firings
Rifle:
SAC 6.5 CM
26" Bartlein barrel
Manners T6A
I have 350 - 3 separate lots of 100, each in a different box with color coordinated brass marks and 50 as "practice and experiment".
If I go to a match that requires 180 rounds, I bring 250. With 350 pieces in play, I should always be able have 250 on hand or loaded up quickly with out having to split lots.
But when one lot gets to about 6 firings, I spool up a new batch of 100 because I toss after 8 firings. So that's 450 at time.
Thanks for the info. I am up to 100 pieces of brass and still have 160 factory 140 loads to shoot. They are shooting 1 ragged hole at the moment so I may just keep buying factory ammo!
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