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homefrontsniper
09-15-2014, 07:08 PM
Have you ever went 1 gr. Over max with .223 / 55 v max
Powder AR COMP/ everything looks good. And very accurate. (26.3 gr)
Thanks

scope eye
09-15-2014, 07:25 PM
Sounds a bit risky, I don't know about those reloading practices, I guess I am just a gun shy pardon the pun.

Dean

LongRange
09-15-2014, 07:55 PM
Not with a 223 but ive blown primers out of cases a few times...if you have no pressure signs you should be ok just dont let the ammo get hot then shoot it or let it sit in a hot chamber for long before firing and NEVER let your buddy shoot that ammo out of his 223...it might be ok in your riffle but may split his riffle wide open.

wbm
09-15-2014, 08:08 PM
1 grain over in a small case like the 223 is a LOT more risky than cases with larger capacity....don't know if AR-Comp is temperature sensitive but if it is you could jump to some very unfriendly pressures in a hurry on a hot day.

scope eye
09-15-2014, 08:18 PM
I was being factitious, load until you start seeing tell tale signs, and if you don't know what tell tale signs are don't do it, until you learn what to look for and recognize them.

Dean

homefrontsniper
09-15-2014, 11:10 PM
Ok . No brass flow in E ..can still see the B on primer.. new brass 0.3745 at head??? After fired it is 0.3750...& no ring of death???
Thanks

gotcha
09-16-2014, 02:52 PM
O.K., so you're using BR-4's ? Reloading manuals are only a guide. You started low and worked up. You may have a "faster" bbl. Growth at head is reasonable. No pressure signs......... How accurate is your scale? Do you have another scale to compare it to? I agree with WBM, with a .223 I'd only go 2 or 3 tenths of grain at a time....... Also, your load data may be a bit on the conservative side. Have you checked other sources for same bullet/ powder combination??

homefrontsniper
09-16-2014, 03:02 PM
Thank you all !!!

gotcha
09-16-2014, 03:05 PM
You said the load was very accurate. My Ol' Pappy used to say: Never look a gift horse in the mouth :)

darkker
09-16-2014, 08:07 PM
Load however you want to load, But for the facts, you need to know some things.

Measuring the case head expansion is better than nothing, but NOT any semblance of a reliable gauge of actual pressure; Less reliable than Copper Crushers.
Copper crushers, which are VERY carefully calibrated, have been shown to report variances on the order of 10,000 psi difference with the same reference load, at that cartridges operating pressure.
That is why Piezo electric, and now strain gauges are used.
How un-reliable? Dr. Denton Bramwell has done numberous honest scientific tests on measuring case expansion.

Assuming that there is ONLY one metalurgical recipe for cartridge cases, is not true. IF they did stick to the metals handbook for cartridge brass, then tensile strength is @ 70,000psi. So when you see case expansion, guess where your pressure are approaching?? Then there is the Assumption of this cartridge brass, which is NOT carefully calibrated, somehow will report pressure closer than Copper Crushers.

$0.02

homefrontsniper
09-16-2014, 08:47 PM
Load however you want to load, But for the facts, you need to know some things.

Measuring the case head expansion is better than nothing, but NOT any semblance of a reliable gauge of actual pressure; Less reliable than Copper Crushers.
Copper crushers, which are VERY carefully calibrated, have been shown to report variances on the order of 10,000 psi difference with the same reference load, at that cartridges operating pressure.
That is why Piezo electric, and now strain gauges are used.
How un-reliable? Dr. Denton Bramwell has done numberous honest scientific tests on measuring case expansion.

Assuming that there is ONLY one metalurgical recipe for cartridge cases, is not true. IF they did stick to the metals handbook for cartridge brass, then tensile strength is @ 70,000psi. So when you see case expansion, guess where your pressure are approaching?? Then there is the Assumption of this cartridge brass, which is NOT care
fully calibrated, somehow will report pressure closer than Copper Crushers.

$0.02


Thanks ! What's your IQ.......do you Work for NASA ;)

darkker
09-16-2014, 10:03 PM
HA! No I don't work for NASA, and can't remember staying at a Holiday Inn...

Just don't believe in voodoo.

Here is one of Denton's articles:
http://www.shootingsoftware.com/ftp/dbramwell%20july%2019%2004.pdf

earl39
09-16-2014, 10:35 PM
Load however you want to load, But for the facts, you need to know some things.

Measuring the case head expansion is better than nothing, but NOT any semblance of a reliable gauge of actual pressure; Less reliable than Copper Crushers.
Copper crushers, which are VERY carefully calibrated, have been shown to report variances on the order of 10,000 psi difference with the same reference load, at that cartridges operating pressure.
That is why Piezo electric, and now strain gauges are used.
How un-reliable? Dr. Denton Bramwell has done numberous honest scientific tests on measuring case expansion.

Assuming that there is ONLY one metalurgical recipe for cartridge cases, is not true. IF they did stick to the metals handbook for cartridge brass, then tensile strength is @ 70,000psi. So when you see case expansion, guess where your pressure are approaching?? Then there is the Assumption of this cartridge brass, which is NOT carefully calibrated, somehow will report pressure closer than Copper Crushers.

$0.02

Darkker i know where all this is coming from and within the parameters of the test i would agree whole heartily but you have not taken into account differences in powder lot and also chamber size which would allow or restrict case head expansion dependent on who and where the exact measurement was taken. As you stated the copper crusher was/is not the most reliable pressure testing device and the Piezo is much better and more consistent. As most of us do not have a Piezo or strain gauge handy we just have to go with what we can see or feel and we all take our chances as does anyone that reloads. Such as, you just bought a brand new pound of your favorite powder and due to a mishap in packaging the wrong label was placed on your bottle of powder and you now have a powder that will create much higher pressure but looks so much like your normal powder you don't notice the difference. Load up your ammo and BOOM. Now do we all say you should have only used factory ammo? Reloading is both a science and an art combined and as has been stated many times in many post the powder we get is for the most part never the same as factory ammo and will change from lot to lot which makes reloading guides just that a guide and not gospel. So if we are going to just stick to the facts then all the facts need to be put out there including how bearing length will change pressure as will barrel twist, barrel coatings such as hbn or moly, or melonite treatment all which reduce pressure by making the barrel slicker. One needs to understand all the ins and outs in a constantly changing reloading environment. External temp will also play a large part in how a given load in a given weapon will produce a useable safe pressure or a dangerous spike.

rant over only trying to get enough facts out there for HFS to make a honest choice in how he chooses to continue. After all it is his face next to the chamber.

homefrontsniper
09-16-2014, 10:48 PM
Delete

homefrontsniper
09-16-2014, 10:50 PM
HA! No I don't work for NASA, and can't remember staying at a Holiday Inn...

Just don't believe in voodoo.

Here is one of Denton's articles:
http://www.shootingsoftware.com/ftp/dbramwell%20july%2019%2004.pdf

Read this people ^

Savage6x284
09-17-2014, 12:00 AM
Get a Pressure Trace and KNOW what pressures are being produced.
Pressure Trace is the only relatively inexpensive system available to gunowners which will yield accurate pressure information for your loads, your rifle, and the environmental conditions pertaining at the moment of firing.
There is/was the Oehler 43 PBL which also measured chamber pressure but 43's are super rare and expensive if you can find one.
Fun, informative and sometimes utterly baffling.

JASmith
09-17-2014, 10:25 AM
Classic reloading advice:


Start 10% below maximum listed load and work up.
A tweak: watch for velocity and accuracy in addition to all those little signs we look for. Choose the most accurate in a place where the velocity doesn't change much.

Additional wisdom from folks who have experienced reloading surprises:


Always repeat whenever a new box of bullets, box of primers, or canister of powder is opened.
Definitely repeat when changing to a different bullet design or brand of cases. ("Definitely" is a stronger admonition than "Always")