How close was these loads to Kaboom???


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Blue68f100
June 30, 2016, 07:20 PM
Earlier this week I had neighbors over shooting at my range. All was going well till my neighbor chamber some 223R, 68-69gr BTHP Match loads. I had my crony setup but was not sending data to my phone app. Any way the first shot registered 3740 fps out of a 16" NATO chamber 1:9 twist. :eek: I told him to stop and lets see whats up. He fired again still in the 3700 fps range. I told him we need to break those down to confirm the load. He wanted to keep shooting so my neighbor and I backed way off. He shot a total of 5, that were off the charts. The other 5 shot loaded at the same time landed in the 2650 fps which is normal.

He came over this morning and I quizzed him on his loads. What I found out was he substituted Hornady 68gr in place of Sierra. He did not think 0.1 gr lighter would make any difference. He was using 24.5 or 25.4 gr (not sure which one) of CFE-223, 2.250" OAL, CCI 41 primer. The brass was A-USA or PPU. Once I found that out I showed him the 2 bullets side by side. For those who are not familiar with these, the Hornady 68 gr bullet is 0.090" longer than the Sierra 69gr HPBT. Hornady recommends a AOL of 2.250" while Sierra recommends 2.260". My data books does not show CFE-223 powder, but Hodgdon's show it for the Sierra 69gr, 23.5-25.8gr. I normally use Varget with these bullets and the max is 1.2gr higher with Sierra's 69gr max at 26.1gr.

So it appears he just swapped bullets, Hornady for Sierra.

This is a good example why you MUST compare bullet profiles before substituting data.

Can some one please plug these number into Quickload to see how close it was to blowing his gun up.:o

Be Safe.

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CarJunkieLS1
June 30, 2016, 07:36 PM
Is it possible that the chrono was too close to the barrel and it was picking up the muzzle flash

Rodentman
June 30, 2016, 07:49 PM
I believe you but that seems like an awfully high velocity. I guess I'm no help with an answer, but I will be following this thread cuz it looks like I may learn something.

VoodooMountain
June 30, 2016, 07:55 PM
I'm very intrigued as to how you can possibly gain 1000fps from a 223/556. I don't have any neat software but my gut is telling me the chronograph is to blame.

How did the brass and bolt head look?

Walkalong
June 30, 2016, 08:21 PM
I would say the chrono readings were off. If he got 3700 FPS with a 68 Gr bullet I can't see how there wouldn't have been some serious pressure signs on the brass.

Can some one please plug these number into QuickloadI'd love to see the numbers.

RandyP
June 30, 2016, 08:31 PM
I question whether a scant .01" difference in OAL would do anything measureable to any caliber? I suspect that factory ammo varies by more than that quite often?

alsaqr
June 30, 2016, 08:32 PM
Something is up with the chrono.

gwpercle
June 30, 2016, 08:36 PM
Hodgdon Load Data shows for 223 with CFE-223 powder and a 69 grain bullet:

starting load : 23.5 grains - 2788 fps

maximum load : 25.8 grains - 3029 fps

3700 to 3740 fps ??? Something is not right , either the amount of powder , type of powder or chrono numbers ! Hard to tell from here. Start over and double check loads and numbers. .01 difference in OAL should not make a difference.
25.4 grains of CFE-223 should be a safe load but not a 3700 fps load ?
Gary

243winxb
June 30, 2016, 08:39 PM
The 68 gr Hornady does have a long bearing surface that will raise pressure with the same powder charge, maybe? But adding 1000 fps, i think the chronograph is to blame. http://i338.photobucket.com/albums/n420/joe1944usa/2016%20Reloading/th_BearingSurface_zpsbac6nfsu.jpg (http://s338.photobucket.com/user/joe1944usa/media/2016%20Reloading/BearingSurface_zpsbac6nfsu.jpg.html)

35 Whelen
June 30, 2016, 08:42 PM
I don't think you could cram enough of that power in a .223 case to achieve those velocities. I've been loading for a shooting a 220 Swift for 30+ years and can tell you in all certainty that even IT isn't capable of 3700 fps with a 68 or 69 gr. bullet.

Now, apologize to your neighbor and check your chronograph. ;)

35W

Nature Boy
June 30, 2016, 08:45 PM
I agree with those blaming the chrono. I get weird readings sometimes. Not sure if it's the angle of the sun or some other factor, but when I get a 168g .308 load clocking at 4,800 fps and the others are in the 2,600 range, and I'm still in one piece, I blame the chrono

Blue68f100
June 30, 2016, 09:11 PM
The crony was 12' from the muzzle, never had a problem with it being off. Missing readings due to sun angle yes. There was pressure signs on the brass, aka ejector marks. You could definitely tell these were hot. With this Hornady bullet taking up 0.1" of case volume is a major bullet setback.

Like I said earlier my load books show 1.2gr less using the Hornady 68gr vs Sierra 69gr using Varget. But I have no idea what these number are for CFE-223.

I need to ask him again what his load was 25.4 or 24.5

Unfortunately I may never know since he shot the 5 out of 10 that were that way. I offered to break one down to see whats going on but he continued shooting.

dragon813gt
June 30, 2016, 09:28 PM
25.4 grains is 103% fill. Pmax is 57,327. Velocity is 2770. To get that type of velocity you would be around 32 grains(130% fill) at a Pmax of 173,252. The pressure/velocity chart is quite amusing.

sugarmaker
June 30, 2016, 10:17 PM
That would be making 82 foot pounds per grain, which is pretty much unheard of in 223.

gunit43
July 1, 2016, 12:07 AM
Chrono.

rcmodel
July 1, 2016, 12:14 AM
There is no possible way you got that much velocity out of a 16" barrel, with that weight bullet without blowing the gun up.

Crono error of some kind.

rc

Mad Chemist
July 1, 2016, 03:19 AM
Chrony malf.

Fire_Moose
July 1, 2016, 03:49 AM
All the same brass? Maybe a few low case volume shells?

Steve C
July 1, 2016, 05:39 AM
It was likely a chrono error as others have suggested. Likely the screens where picking up flash, smoke or powder passing over ahead of the bullet. Did you give the cases and primers a good look. If the primer isn't showing any high pressure signs the extra high velocity probably isn't a correct reading.

Moving the gun back a few yards should correct the reading.

Havok7416
July 1, 2016, 06:06 AM
Had to be the chrono. It certainly wouldn't have been from a bullet/manufacture change without drastically altering the OAL somehow.

WelshShooter
July 1, 2016, 06:34 AM
Definitely the chrono. I've shot a load that was seated with an overall length 0.020" shorter than standard (accidentally, no other factors changed) and in my 6.5x47 Lapua I gained a measly 75fps velocity increase. I've even substituted different brand bullets with all others factors remaining constant and at most there's a 100fps difference with the same bullet weights.

Heck, I shoot 69gr SMK near enough max load out of a 24" barrel and get around 2,800fps with it. No way you could get more than that with a 16" barrel.

In summary, I don't think the change of 1gr bullet weight and 0.010" seating depth would cause a 1,000fps gain. Definitely an issue with the chronograph.

Blue68f100
July 1, 2016, 08:18 AM
These bullets are 0.090" longer so there is a setback of approx .1" not 0.010". I know that 0.010 or 0.020" will not make that much difference. But it was way more that that. 0.030" setback in a 9mm can double the pressure with some powders.

If it wasn't for the bolt marking the brass, primers flattened besides the noticeable sound difference I would have marked it as a bad crony reading. I had just shot my AR and recorded some velocity in the 3350 so I know the crony was working right. My gun has a 24" Bull barrel with a tight chamber. It has consistently been equal to and faster than a lot of published data. There is a flash hider on his gun where I have nothing on mine but that should have helped dispersed the blast. But these were light 55gr bullets, which I was expecting to be fast. Not 68/69gr bullets which are normally pushed in the 2500-2600.

I would still like to see what the QL numbers would be using this combo. For the extra long length makes a compressed load.

It may have been a crony error but I have a problem accepting it due to all the indicators of a very very hot load caused by a 0.090"-0.100" setback.

dragon813gt
July 1, 2016, 08:37 AM
I would still like to see what the QL numbers would be using this combo. For the extra long length makes a compressed load.



I posted the numbers in my previous post.

Jim Watson
July 1, 2016, 09:11 AM
If you could get a free 700 fps just by changing to a different brand of bullet seated a little deeper, it would be regular practice by long range shooters who use strong actions and don't care about brass life.

higgite
July 1, 2016, 09:28 AM
I ran the numbers through QL and this is what it spit out. I got slightly different results than dragon813gt, but in the same ballpark. Take it for what it’s worth.

Cartridge = .223 Rem
COL = 2.250”
Barrel Length = 16.0”
Case = Standard SAAMI .223 Rem
————————————————————————————————————

Bullet = .224, 69, Sierra HPBT MatchK 1380
24.5 gr CFE223
46,411 psi
2590 fps
Seating Depth = 0.407”
Filling/L.R. = 95.3%

Note: The Filling/L.R. number is % of available volume under the bullet that the powder occupies when the bullet is seated to the specified COL.
————————————————————————————————————

Substituting Hornady bullet for the Sierra:

Bullet = .224, 68, Hornady BTHP M 2278
24.5 gr CFE223
48,907 psi
2641 fps
Seating Depth = 0.494”
Filling/L.R. = 98.1%


To get 3740 fps for the Hornady bullet would require:
32.9 gr CFE223
192,086 psi
Filling/L.R. = 131.7 %

In other words, there isn’t enough room under the bullet for that much powder. In fact, there isn’t enough case volume even without the bullet to hold that much powder. A standard SAAMI .223 Rem case will overflow with 30 gr of CFE223.

RandyP
July 1, 2016, 11:21 AM
Well I don't even own a chronograph nor have I personally seen one in use other than a youtube vid and I'M 100% convinced the OP's chrono is the problem.

So that's that I reckon?

hdwhit
July 1, 2016, 12:35 PM
Any way the first shot registered 3740 fps out of a 16" NATO chamber 1:9 twist. I told him to stop and lets see whats up.

blue68f100, I want to commend you for noticing the anomalous velocity reading and suggesting that the shooter stop for diagnosis. That was the absolutely right thing to do. And when your guest wouldn't heed your suggestion, backing up was a prudent thing to do.

Personally, I might not invite that guest back until they understood that when I say "stop", everything on that range stops until we can proceed safely.

Blue68f100
July 1, 2016, 01:40 PM
I ran the numbers through QL and this is what it spit out. I got slightly different results than dragon813gt, but in the same ballpark. Take it for what it’s worth.

Cartridge = .223 Rem
COL = 2.250”
Barrel Length = 16.0”
Case = Standard SAAMI .223 Rem
————————————————————————————————————

Bullet = .224, 69, Sierra HPBT MatchK 1380
24.5 gr CFE223
46,411 psi
2590 fps
Seating Depth = 0.407”
Filling/L.R. = 95.3%

Note: The Filling/L.R. number is % of available volume under the bullet that the powder occupies when the bullet is seated to the specified COL.
————————————————————————————————————

Substituting Hornady bullet for the Sierra:

Bullet = .224, 68, Hornady BTHP M 2278
24.5 gr CFE223
48,907 psi
2641 fps
Seating Depth = 0.494”
Filling/L.R. = 98.1%


To get 3740 fps for the Hornady bullet would require:
32.9 gr CFE223
192,086 psi
Filling/L.R. = 131.7 %

In other words, there isn’t enough room under the bullet for that much powder. In fact, there isn’t enough case volume even without the bullet to hold that much powder. A standard SAAMI .223 Rem case will overflow with 30 gr of CFE223.
Thank you for running those number through QL for me.

What would the data look like with 25.4 gr of CFE-223. I confirmed this was what these were suppose to be loaded too. I know this will be a compressed load as to how much I have not a clue. His seating depth may be a little deeper. Since he made them all the same length at 2.260"-2.255". This puts 0.090" of the bullet deeper into the case.

I scrolled through the data on my crony this morning. There was only 2 at 3704, 3700, with several around 2620-2670. I'm not sure he even used all the same head stamp at this time.

Blue68f100
July 1, 2016, 01:49 PM
blue68f100, I want to commend you for noticing the anomalous velocity reading and suggesting that the shooter stop for diagnosis. That was the absolutely right thing to do. And when your guest wouldn't heed your suggestion, backing up was a prudent thing to do.

Personally, I might not invite that guest back until they understood that when I say "stop", everything on that range stops until we can proceed safely.
We have talked and he agrees he should of stopped and let me tear one down to see the actual end results. This has bugged him too, knowing he may have gone over the edge. The bad thing he could not think of any thing he did wrong till we talked. Once I found out he use a Hornady 68gr in place of a Sierra 69gr I showed him the difference. It had not dawn on him that the bullets were that much difference in length. I also found out that he had a few beers during the loading process. This is after a long day working on ranch/farm. This alone can effect your judgement. I try to express the need to have 100% of your concentration during reloading. All it takes is one mistake for some one to get hurt.

Havok7416
July 1, 2016, 02:11 PM
Another issue that effects chronos are muzzle devices. According to OP one gun had a muzzle break/flash hider and one didn't. One grain difference in the bullet won't cause a substantial difference in velocity, let alone 700 FPS.

hdwhit
July 1, 2016, 02:15 PM
I have an old Shooting Chrony chronograph. I have no way of calibrating it, but believe it has been accurate as the figures it produces are comparable to what is shown in the published load data over a wide range of cartridges and velocities.

Still, optical chronographs are susceptible to false readings due to environmental interference.

This past weekend, I shot roughly 100 rounds of 9mm Parabellum that had been loaded with four different powders to see which loading would give the best performance in my new pistol. The velocities reported were consistent and comparable to what was shown in the published data.

I also brought along 10 rounds of .38 Special. 3.7 grains Green Dot, 158 Grain bullet, per Lee's data supplied with my dies (slightly above the 3.5 published by Alliant in 2004). I had loaded 3.3 grains of Green Dot with the same bullets in November 1993 with no problems, so I was not concerned about stepping up to the figure in Lee's data. I was using these to test the effect of the amount of crimp on performance. Each charge was thrown light and trickled up to weight. This should have given velocities in the 900 fps range. The rounds were themselves consistent. Discounting two that were off-target because I had forgotten the heavy trigger pull on the gun, the remainder ended up in a circle about and inch and a half in diameter at 10 yards. I write this to focus on the chronograph and not have people second-guessing the load or my technique.

These loads produced considerable muzzle flash and this appeared to have an effect on the chronograph situated about 8 feet in front of the firing line as it failed to register five of the shots altogether and returned velocities for the others ranging between 610 and 1351 fps (610, 923, 957, 1197, 1351). I regard all of the data from the .38 Special to have been affected by the muzzle flash and thus unreliable.

Something similar may have happened with the OP's chronograph.

Walkalong
July 1, 2016, 02:32 PM
Every once in a while you'll get a reading from a chrono that simply isn't correct. Sometimes if the sun is down low a chrono will not function properly. Sometimes there isn't any obvious explanation.

If the crazy velocity isn't matched by serious pressure signs on the brass, it isn't right.

I have had times when shooting pistols over a chrono that the numbers have been so bad I just discount them and do it again later. Such as an ES of 450, when you know the load can't that bad.

hdwhit
July 1, 2016, 02:36 PM
I also found out that he had a few beers during the loading process.

From my written reloading procedures:

1. Drinking alcohol within 24 hours of reloading is forbidden
2. Eating while reloading is forbidden.

Being buzzed, tipsy, drunk or hungover when reloading seems to me to be a recipe for disaster. It may seem silly for me to have something so obvious written into procedures only I ever see, but the procedures form the basis for the checklist that goes along with each batch of cartridges and it requires certification that step #1 has been followed.

Jim Watson
July 1, 2016, 04:51 PM
A few beers?
Might be an ex buddy or at least an ex shooting buddy.
Heck, I have preloaded my magazines for tomorrow because I am likely to have a drink at supper.

35 Whelen
July 1, 2016, 05:22 PM
I just found a load out of Rifle magazine that used the Hornady 68 gr. HP over 25.8 grs. of CFE. 2811 fps out of an 18 1/2" barrel. The chromograph is either whacked or was out in direct sunlight when in use. Had this happen many times.

On the drink while reloading, I enjoy a beer while loading. No harm no foul. Funny how folks get all up tight about a beer during a loading session yet think nothing of tossing back a few and then hurling a 2 ton chunk of steel down the rode at 75 mph.

35W

Blue68f100
July 1, 2016, 08:12 PM
Every once in a while you'll get a reading from a chrono that simply isn't correct. Sometimes if the sun is down low a chrono will not function properly. Sometimes there isn't any obvious explanation.

If the crazy velocity isn't matched by serious pressure signs on the brass, it isn't right.

I have had times when shooting pistols over a chrono that the numbers have been so bad I just discount them and do it again later. Such as an ES of 450, when you know the load can't that bad.

My shooting area is shaded by trees, crony in the shade. I only get the mid after noon sun where I'm setup at. I've had bad and missed data in the past, most were sun related (getting to sensors). I never set the crony up less than 12' which as worked for me up to now. May start moving it back to 15' so this may not happen again.

The brass did show signs of over pressure, I said this in my original post. Extractor imprinted on the base, brass swipes, primers where flattened to very little rounded edge left. These were the CCI 41 which are pretty tough. None of them blew though, and none fell out on their own.

As far as my neighbor, I rather help him out so he does not make the same mistake. He has been reloading as long as I have, 4 decades. But he has had 4 heart attacks which has impacted his memory recall. And he's 5 yrs older than I am. A Vietnam veteran with PTSD too. So he has some health issues he's dealing with too. If I mention something a lot of time it triggers his recall. Other wise he may be lost trying to think of it till he asks a question. Some times I have to explain things several times before it sinks in.

I've been working on his documentation, record keeping. He writes loads on the side of paper ammo boxes, inside on the sleeve but does not date them so you don't know what it is. He does since he know the last entry. I gave him a stack a labels to use, hoping it will clear some of it up.

Walkalong
July 1, 2016, 08:55 PM
The brass did show signs of over pressure, I said this in my original post. Extractor imprinted on the base, brass swipes, primers where flattened to very little rounded edge left.Obviously that is too hot, but not 3700+ FPS ("serious") hot. :)

I always put the chrono at 5 paces. Works for me. Most of the time anyway.

higgite
July 1, 2016, 09:22 PM
What would the data look like with 25.4 gr of CFE-223.
Blue,

For the same bullets as before over 25.4 gr CFE223, QL says:

Sierra bullet
52,463 psi
2700 fps
98.8% Fill

Hornady bullet
55,535 psi (This is above SAAMI max of 55,000 psi for .223 Rem)
2754 fps
101.7% Fill

Jesse Heywood
July 1, 2016, 09:36 PM
As far as my neighbor, I rather help him out so he does not make the same mistake. He has been reloading as long as I have, 4 decades. But he has had 4 heart attacks which has impacted his memory recall. And he's 5 yrs older than I am. A Vietnam veteran with PTSD too. So he has some health issues he's dealing with too. If I mention something a lot of time it triggers his recall. Other wise he may be lost trying to think of it till he asks a question. Some times I have to explain things several times before it sinks in.

I've been working on his documentation, record keeping. He writes loads on the side of paper ammo boxes, inside on the sleeve but does not date them so you don't know what it is. He does since he know the last entry. I gave him a stack a labels to use, hoping it will clear some of it up.

At my cardiologist I asked about major short term memory issues. The tech told me that it is a big problem, depending on how long your brain was deprived of oxygen. That is the reason his thought process goes tilt, and it is frustrating as he11. In my case, the key to overcoming this is structure and repetition. One of my problems is with taking my meds. I had to set up a routine. I have to do it one step at a time, with clues to tell me what I just did when I have a brain fart. My motto: I probably can't tell you what I had for breakfast. But I can tell about things I did at the age of 2.

The labels are a good idea. I would also make him a notebook to track what he did at the bench. Walk him through filling it out, but do not do it for him. You don't want to be an aggressive teacher. If his train of thought derails, say something like "thinking" in a quiet voice. Also, give him a place to note how he felt that day.

The secret is to work these things with being demanding or pushy. Work in a world of what-ifs. He will probably start butting heads and resisting. If it gets to that point, take a break for a cup of Joe. And if he hasn't rebalanced, leave and return later.

Remember, you are dealing with a man who can be as lost as a child in a forest. But, he is a man, who's pride is hurt in addition to the panic of the child. You will be the mentor, guiding but not leading, encouraging but not pushing. He desperately needs your help, but will not ask for it and doesn't want it. May God bless you as you proceed.

RandyP
July 2, 2016, 12:05 AM
To the OP, maybe it's time to gently suggest to your friend and neighbor that he only reload when you can join in on the session? There is no telling what powder or charge he 'could' be using by mistake? His safety comes first.

As a Vietnam Vet myself tell him thanks for his service and welcome home brother for me.

Jim Watson
July 2, 2016, 07:31 AM
"Shaded by trees".
The flicker of light leaking through the leaves will scramble chronograph readings.
BTDT, not theory.

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