View Full Version : Help with 223 pressure signs
Hello and thanks in advance. Shot my first reloads using H335, mixed once fired brass, Remington 7.5 bench rest primers. 55 grain fmj bt Hornady.
Picture is left to right, 22.9, 23.5,23.8,24.8 and 25.1 grains. Last 3 being 25.1.
The 25.1 were most accurate.
So based on my research there doesn't seem to be any pressure issues but I would appreciate some feedback.
I am a little concerned about the circular pattern around some of the primers.
Thanks!
michael word
03-31-13, 19:11
Dont see any signs to me.
anachronism
03-31-13, 19:46
The circles around some of the primers are remnants of the crimp that was originally used to hold the primers in place in military cases. Civilian cases don't have crimped in primers, except for some Federal loads. Federal 223 brass really needs to have the primers crimped in, trust me.
m1a_scoutguy
03-31-13, 19:52
Dont see any signs to me.
Looks fine to me !!! If there is some flow of the primer ,,kinda like a ridge around where the firing pin dimples the primer,,then yes,,,there is some extra pressure !! But for me the pics of the fired shells/primers look fine !! Looks like your still a few "tenths" under Max of 25.3 so I would go with it as long as your getting good cycling/function !!
Thanks guys.
Rifle cycled fine with all the different loads. Lighter charges were a bit of a spray but the closer I got to the 25.1 the better the groups.
Overall pretty satisfied with my first reloading experience.
I don't like H335 because of the big flash... but when I do load it, it's 25.0 for me. Seems to be a decent, stout.. but not too hot load.
Mbowman
Yep those are fine. If the 25.1 gr is accurate enough for you I'd stop there and mark it your record for the load to use!:D Load up ten and fire a group so you have a target for your record. Do it at 100 yards!
IMO the last one and possibly the next to last "appear" to show some extractor and/or ejector marks - last one = bright spot on the case head from the extractor groove; on the 3rd to last a small splinter coming off the rim. This is not unusual for 5.56 pressure loads but probably above .223 pressure.
Those look fine. If you're curious, do a google image search for "flattened primer."
I use a pair of vernier micrometers and measure the web for gross expansion, among a couple other items/tools....Crony is good way to tell if too hot.
Those look fine. If you're curious, do a google image search for "flattened primer."
Flattened primers and primer flow are not gospel signs of high pressure.
Those need to be taken in context and can vary due to primer cup thickness.
Flattened primers and primer flow are not gospel signs of high pressure.
Those need to be taken in context and can vary due to primer cup thickness.
That is absolutely true, sorry if I implied otherwise. I was only commenting on the primers shown, that is not the only thing to check.
Here is a view of the 25.1 cartridges
To me, that looks OK. I don't see any ejector swipes or excessively flattened primers. 23.5 is a good starting point for H335 with a 55 gr bullet, and I normally load to 24.0-24.5 with either a 52 or 55 gr Hornady bullet. Shoots great, excellent accuracy. If 25.1 gr shoots well for you, load away. Just be aware that it is around book max according to Hornady.
As noted prior, the best way to watch for excessive pressure is not looking at primers but measuring the case web for growth, and monitoring the primer pocket tension. High pressure = loose pockets in 2-3 firings.
However, lots of other things can change pressure. Case length, OAL, chamber, etc.
Good luck!
Good feedback. I will watch for loose primer pockets and work on a way to try to measure web. Lots to learn.
Thanks to all!
Good feedback. I will watch for loose primer pockets and work on a way to try to measure web. Lots to learn.
Thanks to all!You can use calipers, but the vernier http://www.midwayusa.com/product/169644/lyman-vernier-micrometer-1 are more precise... and just in case here ya go http://www.exteriorballistics.com/reloadbasics/index.cfm
JMTC... Beware of pressures that increase in hot weather like 95 in the shade.
I found that this powder is a little sensitive to temps. I developed an accurate load in the winter using this powder at 25.0g. Load was stout but showed no pressure signs and when I re shot the load in summer time I started to get flattened primers and slight flowback as well as decreased group size such as .5moa larger when hot. I backed down to 24.5g and it seems to be a happy medium.
The best overall powder for the 55g bullets I have found is XBR 8208.
I use this at 25.8g under 55g Midsouth Shooters Varmint Nightmare's
and get .410" to .425" groups at 100 through a 1/8 DPMS SPR barrel. The load is consistent accros all temps That I shoot in, (35 to 105 F)
Good luck!!
Good feedback. I will watch for loose primer pockets and work on a way to try to measure web. Lots to learn.
Thanks to all!
If you're only near max published... forget worrying about web measurements. You can feel loose primer pockets when you seat primers.
That's how I cull my brass.
They look fine, primers aren't flat (so I wouldnt think the cratering is excessive or an issue), no swipes... you might want to do a google picture search of pressure signs to familiarize yourself for what to look for.
Pressure signs:
I look for primer flow into the firing pin hole and on ARs, impression from the ejector on the case head.
Measuring case expansion has to be done in .0001 that is one ten thousands of an inch increments. I have not yet met the commercial grade caliper that can reliably or repeatedly do this.
From what I have read, case head expansion is properly measured across the extractor groove with a .0001 reading blade micrometer. Also from what I have read this method of pressure measurement has been mostly discredited for general use.
Case head expansion also causes loose primer pockets - a much simpler thing to detect.
It's important not to go overboard on measuring every ****ing thing with calipers and what not. I did that crap in the beginning of my reloading carrier years back and it only made slap crazy finnicky 45 acp ammo.
Then I realized that most of these dimensions don't even check out on your favorite factory loads.
I've probably NEVER done most of the measurements mentioned here and have loaded literally TONS of .223 for the AR and Bolt guns... up to and including 1/4 MOA match ammo.
Get your correct OAL so the ammo fits in a mag, and get a Case guage... You'll be set.
markm
Yep I stop doing all that crap as well! Now with a chrony I shoot for a target velocity and accuracy. Looking for pressure signs! Most of my loads are below max as thats where the accuracy is 90% of the time!:D
I'm glad I found this thread..I was out yesterday, and crony'd a load I was working up..(30rnds)Using once fired mil brass (mostly LC 04'-09') brass, hornady FMJ 55gr loaded at the cannulre 2.200, using 24.6 H-335, I got the following... shot from DD LW 16' bbl, with crony 11'6" from end of barrel..At 10' from bbl, I was getting some crazy readings.. I can only attribute to muzzle blast. No pressure signs were observed...
1.2882 fps Lo 2868 fps
2.2964 fps Hi 2964 fps
3.2944 fps Av 2917 fps
4.2942 fps ES 96.24
5.2886 fps SD 35.32
6.2880 fps
7.2896 fps
8.2821 fps
9.2964 fps
10.2913 fps
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.