Are these loads low pressure? *Pictures*

[Lavid2002]

Hi guys. This is very fristrating. Ive reloaded about 10 batches of .223 (50 rds per batch) mostly stuff with m193 rounds. And every.....single....batch ive made has come out with signs of low pressure.

Im a new reloader so please correct me if im wrong, but I cant seem to get signs of med-higher pressure...not even normal pressure! Here are the clues im going off of.
*Dirty case walls
*Primers dont even flatten a little bit.

I reload .308 as well and im yet to have signs of low pressure with that gun. Its outstanding! But my .223 on the other hand doesnt like me. Ive reloaded these batches. Ill give you 3 examples from the 16 batches of low pressure.
Note:All batches are using either rem, WCC, LC, or r&p brass. They also ALL have 9 1/2 small rifle BR remington primers.

1)62 grain FMJ BT, 22 grains of IMR-4895
2)M193 (55gr FMJBT), 24.5 gr IMR4895
3)M193, 26 grains of varget (This is where I got ****** because my loads were ALL low pressure so I tried a compressed load near maximum.) I loaded these things to the brim any more and the powder would have fell everywhere. I know they say you can load em with 27.3 grains of varget[from the jar] but that much wouldnt fit. So I loaded these up and STILLL STIL STIL STILLLLLL HL;DFAVEJF got low pressure : ( I took some pictures for everyone so maybe you can help me. This is rediculous. Ill go to the range, shoot 50 rounds and have to run a bore snake or the bolt wont even close! Also, if you try to clear a round and you havnt cleaned the bore in like 20 rounds then you have to perform a stock slam. Not very safe to do all the time. Please reccomend some loads or powders for me.
I placed some live rounds next to the dirty ones for perspective.

One more thing...do you see those cuts in the WCC casing headstamps. What the heck are those slits from, theres one on almost every round and it NEVER happens with any of my other brass. Rem, LC, Aguila, etc.. Only WCC

 

[Unclenick]

I ran your data in QuickLOAD with a case that has 28.8 grains of water capacity and with the bullets seated to 2.260" COL.

The first load gave 41,000 psi. Pretty low for the .223. You really can't fit enough 4895 in the .223 case to do well with that bullet weight. It's a little too slow for that.

The second load has the same problem. About 45,000 psi.

The Varget load is more reasonable at 52,600 psi, but is not maximum.

The last load of Varget gave 62,000 psi, which is the CIP maximum for the .223 cartridge. But here's the rub: the 28.8 grain water capacity for the case is small. Most of QuickLOAD's default case capacities are on the small side because that creates a worst case for pressure. It showed the last Varget load compressed at 115% of case capacity. That would be very hard to fit in the case if it really had that capacity, so I am guessing your case capacity is larger and I would need to know the water capacity of a fired case from your gun to estimate your actual working pressures. There is a good chance they are all on the low side still.

The basic problem is the powders you chose are really too slow for the bullet weights you are using. Varget shines with the 69 grain Sierra MatchKing and the also their 77 grain offering. 4895 can work well in that same weight range. You're probably going to do better with IMR or H 4198 for the 55 grain bullet. Accurate 2015 would be another good choice for the light bullet.

The 62 grain bullet can be loaded with 4198, though it is maybe a little faster than you want for best performance with it. Benchmark or Reloader 10X may get you a little more out of it. 2015 will work fine with it and the 55 grain bullet, both. Maximum velocity with this bullet will likely come from either Winchester 748 or Hodgdon BL-C(2), either of which should be combined with a magnum primer for best burn (ball powders tend to need the extra ignition boost).

By the way, when looking through the manuals, because case capacity affects pressure significantly, you really need to match the brass brand listed and the seating depth listed to get close to the same performance shown. If you think you are under or over loading, a chronograph can give you some useful feedback.

Finally, pressure signs are like vague hints. You need to watch for them all. None of them reliably proves anything by itself, reading primers included. I've seen a picture of a burst gun whose primer still had rounded corners. If your chamber has tight headspace or if you are neck sizing only, the primer has little opportunity to be backed out by pressure and re-seated as the head stretches back, as happens in the usual firing cycle. In the absence of backing out, during which time pressure can slightly expand the primer diameter so its edges flatten on re-seating, rounded corners are preserved to higher peak pressures.

 

[Lavid2002]

Outstanding. I have some 2015 should I load up some M193 with that? Its faster burning and it may yeild some better results right? I am full length sixing every single time with hornady dies so I dont see why my brass would have any more volume than any other .223 (I know the brand effects it) Thanks for taking the time and entering all that information : D
That computer is pretty nifty, but what do you mean by "My last load" Are you saying the 26 grain varget load had 61,000? Or are you talking about what varget reccomends on the can (27.3)?

Thanks for the help!
: D Dave


P.S. Any reccomended loads?

 

[flashhole]

Nicks advice is very good. From your description one might conclude your gun has a generous chamber. Do you see a lot of movement in the brass when you FL resize?

My 223 is a Kimber Longmaster Classic bolt gun. They advertise it as having a "tight" chamber and it does. I measure very little difference between FL resized cases and fired cases from my gun. My best load is a Sierra 63 grain bullet over a full case of Varget. That is very similar to what you are loading. Pressure on my loads is very good (probably attributed to the tight chamber) and I have good success just neck sizing after the brass is fire-formed.

My brass is nothing special, just range pickup that I sort and process. I try to keep it segregated by head stamp and put them into service when I get 100 or more of the same, and yes, the military brass has less powder capacity. Seems I spend an inordinate amount of time prepping brass but the results are worth it.

I have tried Reloader 10x, it's a bit faster and may solve your problem. I sometimes use a taper crimp die with my 223 loads just for the peace of mind that they are as uniform as I can make them. In theory it would keep the pressure up a bit but I can't make that claim for certain.

 

[wwmkwood]

Are you shooting these out of a carbine length AR? You may have a timing issue, those marks are from your extractor and may be a sign of over pressure. They may also be from a dirty extractor or slightly thicker rim, take your bolt apart and check how tight your extractor fits those rims.

 

[Unclenick]

Lavid2002,

Wwmkwood makes another good point. I just assumed that your casehead shot included cases that had been loaded across the range of loads you listed, which would mean some of them had been fired at rather low pressure. If they are only from your last load, however, then they could be a pressure sign.

Pull the bolt and run your finger over the extractor to see if it stands too proud in the bolt face? I am out of town and away from my books, and I don't recall the dimensional tolerance. If you PM board member Walt Kuleck (username, wjkuleck), he can tell you, I'm sure. He is part of Fulton Armory which builds match guns and he is co-author of several books on arms assembly and disassembly, including The AR-15 Owner's Manual and AR-15 Assembly Guide. He could tell you most quickly how to check for a problem there? Assuming those marks appeared on the cases with the first load you listed, though, then they are happening without high pressure.

On case capacity, the reason it is variable is different internal case dimensions. SAAMI specs for commercial cartridge case brass are only for the external brass dimensions, leaving the internals up to the manufacturer to design. Military brass has both specified external dimensions and has to meet certain performance specifications, but, AFAIK, the specific internal dimensions needed to meet those requirements are still up to the maker. UNS C26000 70:30 cartridge brass has a density of 8.53 grams per cubic centimeter. If the external dimensions are fixed, it follows that a lighter case has less brass taking up volume on the inside than a heavy one does. The weight difference thus accounts for the difference in internal volume.

An example that illustrates some extremes is the .308 case. Winchester uses a semi-balloon head case design that weighs about 156 grains on average. It has about two grains more water capacity than a Lapua case that weighs about 171 grains, and three more grains of water capacity than an IMI Match case which weighs about 186 grains. The Lake City Match brass I have weighs about 180 grains. They all have the same external dimensions and the same size primer pockets, but their internal volumes are all different.

If you look at a high sample rate laboratory graph of chamber pressure measured by a strain gauge, you see a brief stall in the pressure rise at around 30,000 psi where the brass yield is surpassed and the case wall at the edge of the head experiences plastic stretch to let the case head move back to touch the bolt face, thus forming the pressure ring on the inside. This expands the volume the powder is burning in and lowers the peak pressure the chamber sees. Peak pressure in a case loaded to exceed about 30,000 psi is thus determined by the volume it fireforms to in the chamber rather than the volume it is sized to.

To help find your specific case volume, I have an Excel file in my file repository to help. It includes instructions. Basically, though, you will weigh a fired case, then fill it with water level with the top (no meniscus) and weigh it again. The difference in the two weights is the case water capacity. My Excel file also calculates water density for the water temperature you use, and takes that small adjustment into account. It also asks you to enter the case length but the current version doesn't do anything with that information. It is just there to make a record to use in QuickLOAD which needs that to calculate the volume subtracted by the bullet at different seating depths. It also determines sized case capacity in a second column to be used to figure the point at which the powder loaded becomes compressed.

If you PM me with your fired case water capacity and length, that is enough information to give you a better pressure estimate for the 2015 and to recommend a starting and finishing load length that are specific to your gun.

 

[Lavid2002]

AHHHHH;QEWFKJBQWE;RJKFBW;BFER;IEHFRPIQWEHROUWYQEGRLPIUQWGEUI;QGHWEDLHWPEIFUYGQWIERUF!!!!!!
i JUST SPENT ABOUT AN HOUR WRITING UP DIMENSIONS ANSWERING EVERYONES FRIGGIN QUESTIONS AND CAREFULLY MEASURING WATER AND STUFF AND WHEN I POST MY SUPER LONG SUPER EXTENSIVE POST IT SAYS LOG IN, I DO SO AND IT SAYS FAILURE TO LOG INTAHHHHHH!!!!

im sorry im freakin out I just spent so much time and effort on the write up and now I have to do the whole #$^#$% thing all over again! #$^#$!!!!!

 

[Lavid2002]

I hope this answers everyones questions

Are you shooting these out of a carbine length AR? You may have a timing issue, those marks are from your extractor and may be a sign of over pressure. They may also be from a dirty extractor or slightly thicker rim, take your bolt apart and check how tight your extractor fits those rims.

I am shooting a RRA mid-length A4. During the last write up that I spent SO MUCH FRIGGIN TIME ON I constructed a little picture with some measurements of my extractor.

*Image copied from google, however the measurements are MY measurements from MY caliper used on MY extractor for the purposes of this thread* For clarification.

Wwmkwood makes another good point. I just assumed that your casehead shot included cases that had been loaded across the range of loads you listed, which would mean some of them had been fired at rather low pressure. If they are only from your last load, however, then they could be a pressure sign.

I used the same reload in a suggested starting load from lymans reloading manual only to yeild the same scratches. This led me to beleive pressure was a non-issue.

Im too lazy to do the math all over again but heres what I concluded from my casing situation. My WCC 06 casing holds 18.9ml of water.
Using basic conversions I concluded one ml of water is equal to 15.43 grains of powder and used this to determine how much my casing held. 18.9x15.43=291.627grains. If my calculations are right this is how much my casing holds. 291.627 grains of water. My mom is in the medical profession so I use a very small syringe to find out how much the primed casing would hold, with no miniscus of course. Hopefully these measurements and weights are enough for you to find out a good 2015 load.

Thanks everyone!-Dave

I would continue to answer questions like I did in my first write up but im replied-out for the night that thread thing urked me. I should have copied it before I attempted to post so if it failed...and it did...It would be a small fix.

 

[flashhole]

If you have WORD you can do it there first then copy and paste.

 

[PCJim]

Lavid, you might want to review UncleNick's reference link in his post for the calculation of water volume for your cases. Based on his instructions should weigh the case before and after filling with water instead of using conversion tables for the water weight.

UncleNick, VERY USEFUL information contained on your site. Thanks for making it available to us.

 

[Lavid2002]

I tried, but the scale I have is only a lee balance scale. It only goes up to 110 grains. The WCC case weighs 95.1 grains, and filled with water (If my measurements and conversions are correct) It weighs nearly three fold that ammount! I dont know any other way I can measure it other than the method I used. Ideas?

 

[PCJim]

Lavid, OK this "might" work.

Weigh your empty case as UncleNick describes in his spreadsheet, then fill it with water. Set your scale to 90gr, and slowly begin pouring the water into the pan. When it gets to appx 90, stop and record an accurate measurement of the weight of the water. Dump and dry the pan, then pour again, stopping to record the weight. Repeat this until all the water is out of the case. Finally, reweigh the case so that you include any residual water remaining inside.

Although not as easy as a single weighing, and unfortunately allowing for potential errors, it should work.

 

[Lavid2002]

Ahhh, The residual water inside the case will occur after each filling, but its worth a shot. Let me go weigh...it would be funny if I got the same weight as I did with my conversions.

 

[Lavid2002]

WCC casing with primer=98.9 grains

During this test I just filled a casing, and dumped that water into the dish of my scale and weigh IT! lol
water weighed 29.4 grains
A remington primer weighs 3.5 grains

Casing.....98.9
-Primer......3.5
=............95.4 Grains for an empty casing

Water..............29.4 grains
+Empty Casing..95.4 grains
=...................124.8 grains *Note this measurement is partially innacurate because of the residual water lost when its left inside the casing.

Hope this helps : D

 

[Unclenick]

Did you weigh the case dry then wet to see if it gained any weight from residual water? They should hold about 1.9 milliliters of water, so I think you got a decimal point out of place with your original measurement. 29.16 grains is what you would have had with that error. Pretty close to what you weighed, but the weighing is more precise.

29.4 grains is going to be pretty close for a military case, I expect. What length does the caliper say that case is? What COL do you seat those bullets to? I need both those bits of information for the estimate.

 

[PCJim]

I thought I had identified the need to weigh the case both before and afterwards, but did not make it real clear after rereading my post (funny how that happens).

Lavid, you should redo your weighs. You will need the weight of the case both before adding water and after weighing the water. The difference, if any, between "before water" and "after water" weight of the case will be additional or residual water, as UncleNick has stated. The primer weight does not need to be subtracted, as the point of the exercise is to determine case volume by measurement of water weight. As long as the primer remains in the case for both dry and "residual wet", an accurate water weight will be obtained.

Consider me to be just hanging around so I can learn a bit more......

 

[Lavid2002]

All do respect, I beleive the difference in weighs from my innacurate measurements (Wich have ALLOT of human error) Will be greater than any difference in my .223 casings than...oh say bobs, or nicks, etc...

I dont really know how to say this. Lets say my casings have a internal volume of bleh bleh bleh. I will measure this as accurately as I can. Although my measure ment is close it is still someone crude.

The difference between a LC case and a WCC case will be less than my margin of error. I think I need a proper scale to weigh this. Since I dont I beleive referring to the "Standards" for WCC brass will be close enough. No?

As for the COAL I sead to mid-conneleur. About 2.222", and the cases are freshly trimmed to 1.750"

 

[Lavid2002]

: ( Im still having problems. I changed over to XMR 2015. I started at 22 grains behind a 55 gr FMJBT bullets and a remmy 7 1/2 BR primer. These were low pressure. I gradually worked em up and I have them in incremints up to 24 grains. Hopefully these bad boys will get the job done.


My rifle is completely unreliable when shooting reloads like this. Every 30 rounds MAX I need to bore snake it. Thats how dirty tis chamber gets. I end up getting FTFs, FTEs and its all because of a dirty chamber....nonesence.

 

[Unclenick]

I think 24 grains will be getting to more normal load pressures, though a 2 grain jump is a lot in the .223. Half a grain per increase for testing is more normally used to ensure no pressure spike occurs. It depends on your fired case capacity, as I indicated earlier. That capacity will vary up to three grains of water capacity across brands of cases, which is significantly more than your human error will be on a proper loading scale. Even the Lee powder scoops will usually stay within half a grain or so, which is smaller than the differences in case capacity can be.

 

[Lavid2002]

Wow three grains! Thats amazing! I never knew they could vary that much. Where is the difference? In the thickness of the wall around the flash hole im guessing right?